U.S. patent application number 16/965557 was filed with the patent office on 2021-02-18 for logic circuitry.
The applicant listed for this patent is Hewlett-Packard Development Company, L.P.. Invention is credited to Michael W. CUMBIE, James Michael GARDNER, Scott A. LINN, David N. OLSEN, Stephen D. PANSHIN, David Owen ROETHIG, Anthony D. STUDER, Jefferson P. WARD.
Application Number | 20210046760 16/965557 |
Document ID | / |
Family ID | 1000005225534 |
Filed Date | 2021-02-18 |
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United States Patent
Application |
20210046760 |
Kind Code |
A1 |
GARDNER; James Michael ; et
al. |
February 18, 2021 |
LOGIC CIRCUITRY
Abstract
In an example, a method comprises, by logic circuitry associated
with a replaceable print apparatus component installed in a print
apparatus, receiving a sensor data request and determining whether
the request is for data indicative of a print material level or for
data indicative of a pressurisation event. In the event that the
request is a request for data indicative of the print material
level, the method may comprise responding with a first data
response in a first value range; and in the event that the request
is a request for data indicative of a pressurisation event, the
method may comprise responding with a second data response in a
second value range.
Inventors: |
GARDNER; James Michael;
(Corvallis, OR) ; LINN; Scott A.; (Corvallis,
OR) ; PANSHIN; Stephen D.; (Corvallis, OR) ;
WARD; Jefferson P.; (Vancouver, WA) ; ROETHIG; David
Owen; (Vancouver, WA) ; OLSEN; David N.;
(Corvallis, OR) ; STUDER; Anthony D.; (Corvallis,
OR) ; CUMBIE; Michael W.; (Corvallis, OR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hewlett-Packard Development Company, L.P. |
Spring |
TX |
US |
|
|
Family ID: |
1000005225534 |
Appl. No.: |
16/965557 |
Filed: |
April 5, 2019 |
PCT Filed: |
April 5, 2019 |
PCT NO: |
PCT/US2019/026161 |
371 Date: |
July 28, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/US2018/063624 |
Dec 3, 2018 |
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16965557 |
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PCT/US2018/063630 |
Dec 3, 2018 |
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PCT/US2018/063624 |
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PCT/US2018/063631 |
Dec 3, 2018 |
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PCT/US2018/063630 |
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PCT/US2018/063638 |
Dec 3, 2018 |
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PCT/US2018/063631 |
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PCT/US2018/063643 |
Dec 3, 2018 |
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PCT/US2018/063638 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 2213/40 20130101;
B41J 2/17546 20130101; G06F 13/42 20130101; G06F 21/44 20130101;
G06K 15/4075 20130101 |
International
Class: |
B41J 2/175 20060101
B41J002/175; G06F 13/42 20060101 G06F013/42; G06F 21/44 20060101
G06F021/44; G06K 15/00 20060101 G06K015/00 |
Claims
1. A method comprising, by logic circuitry associated with a
replaceable print apparatus component installed in a print
apparatus, receiving a sensor data request; determining whether the
request is for data indicative of a print material level or for
data indicative of a pressurisation event; and in the event that
the request is a request for data indicative of the print material
level, responding with a first data response in a first value
range; and in the event that the request is a request for data
indicative of a pressurisation event, responding with a second data
response in a second value range.
2. A method according to claim 1 further comprising measuring
sensor data in response to the sensor data request.
3. A method according to claim 1, wherein responding to a sensor
data request comprises determining whether the sensor data request
is for data indicative of a print material level or for data
indicative of a pressurisation event based on an identifier.
4. A method according to claim 1, further comprising, prior to
returning the first or second data response, storing the first or
second data response in a predetermined memory location.
5. A method according to claim 1, comprising, in response to
receiving the sensor data request, acquiring the first or second
data response and prior to returning the first or second data
response, receiving a request to supply the acquired first or
second data response.
6. A method according to claim 5 in which the sensor data request
includes a write command and the request to supply the acquired
first or second data response includes a read command.
7. A method according to claim 1, further comprising receiving the
request and returning the first and/or second data response via a
communication bus.
8. A method according to claim 1, further comprising, prior to
receiving the sensor data request, and in response to a first
command indicative of a time period sent to a first address of
processing circuitry via a communications bus, enabling, by the
processing circuitry, access thereto via at least one second
address for a duration of the time period.
9. A method according to claim 8 wherein the second address is
configured to be an initial second address at the start of the
first time period.
10. A method according to claim 9 comprising reconfiguring, by the
processing circuitry, the initial second address to a temporary
address in response to a command sent to the initial second address
and including that temporary address during the first time
period.
11. A method according to claim 9 comprising, on receipt of a
subsequent command indicative of the task and the first time period
sent to the first address, configuring the processing circuitry to
have the same initial second address.
12. A method according to claim 1, further comprising, prior to
receiving the first command, responding to a first validation
request to a first address associated with the logic circuitry with
a cryptographically authenticated validation response.
13. A method according to claim 12 in which the first and second
data responses are not cryptographically authenticated.
14. A method according to claim 1, comprising, prior to receiving
the sensor data request, calibrating data response parameters.
15. A method according to claim 1, which comprises receiving a
plurality of data requests for data indicative of a print material
level or data indicative of a pressurisation event, and returning a
plurality of first data responses in the first value range, or a
plurality of second data responses in a second value range
accordingly.
16. A method according to claim 15 wherein: if a plurality of first
data responses is provided, the plurality of first data responses
comprise a sequence of data readings having a step change, and/or
if a plurality of second data responses is provided, the plurality
of second data responses comprise a smoothly varying sequence of
data readings.
17. A logic circuitry package configured to: communicate with a
print apparatus logic circuit, determine whether a sensor data
request received from the print apparatus logic circuit is for data
indicative of a print material level or for data indicative of a
pressurisation event; and in the event that the request is a
request for data indicative of the print material level, respond
with a first data response in a first value range; and in the event
that the request is a request for data indicative of a
pressurisation event, respond with a second data response in a
second value range.
18. A logic circuitry package according to claim 17 configured to:
receive a plurality of data requests for data indicative of a print
material level or data indicative of a pressurisation event; and
return a plurality of first data responses in the first value
range, or a plurality of second data responses in a second value
range accordingly, wherein: if a plurality of first data responses
is provided, the plurality of first data responses include a
sequence of data readings having a step change, and/or if a
plurality of second data responses is provided, the plurality of
second data responses include a smoothly varying sequence of data
reading.
19-45. (canceled)
46. A replaceable print apparatus component including an I2C
compatible logic circuitry package, wherein the I2C compatible
logic circuitry package comprises: an I2C interface including a
data contact to communicate via an I2C bus of a host print
apparatus; a memory comprising data representing print liquid
characteristics, the data retrievable and updatable via the data
contact; wherein the package is configured to transmit data
including said data representing print liquid characteristics to
the bus over the data contact; and wherein the package is further
configured to communicate with a print apparatus logic circuit, and
to respond to a first sensor data request received from the print
apparatus logic circuit by returning a first response, and to
respond to a second sensor data request received from the print
apparatus logic circuit by returning a second response, wherein the
first sensor data request is a request for data or a first sensor
type and the second sensor data request is a request for data or a
first sensor type, and the second response is different from the
first response.
47. A replaceable print apparatus component according to claim 46
wherein the I2C compatible logic circuitry package is configured
to: in response to a first authenticated command received through
the data contact, decode the command and respond with an
authenticated message authenticated using an authentication
feature, in response to at least one second authenticated command
received through the same data contact, the command including a
second I2C address and a timing period, set at least part of the
logic to respond to commands directed to the second address, start
a timer to determine the end of the timing period, after start of
the timer, respond to messages sent to the second I2C address,
during at least part of the timing period by providing the first
and second responses, and after the timing period, respond to
messages addressed to the first I2C address and not to the second
I2C address.
48. A replaceable print apparatus component according to claim 46
wherein the I2C compatible logic circuitry package is configured to
carry out the method of any of claims 1 to 16.
Description
BACKGROUND
[0001] Subcomponents of apparatus may communicate with one another
in a number of ways. For example, Serial Peripheral Interface (SPI)
protocol, Bluetooth Low Energy (BLE), Near Field Communications
(NFC) or other types of digital or analogue communications may be
used.
[0002] Some 2D and 3D printing systems include one or more
replaceable print apparatus components, such as print material
containers (e.g. inkjet cartridges, toner cartridges, ink supplies,
3D printing agent supplies, build material supplies etc.), inkjet
printhead assemblies, and the like. In some examples, logic
circuitry associated with the replaceable print apparatus
component(s) communicate with logic circuitry of the print
apparatus in which they are installed, for example communicating
information such as their identity, capabilities, status and the
like. In further examples, print material containers may include
circuitry to execute one or more monitoring functions such as print
material level sensing.
[0003] Disclosures discussing data stored on, and pertaining to,
print apparatus components include EP patent publication No.
0941856, and international patent application publications Nos.
WO2015/016860 and WO2016/028272, and US patent publication No.
6685290. Disclosures of communication and authentication circuits
for print apparatus components include US patent publication Nos.
9619663, 9561662 and 9893893. Examples disclosures discussing print
material sensors and sensor arrays for print apparatus components
include international patent application publications Nos.
WO2017/189010, WO2017/189011, WO2017/074342, WO2017/184147,
WO2017184143, and WO2018/022038. Example disclosures discussing air
and pressure regulation include US patent publication Nos. 8919935,
9056479, 9090082, 8998393, 9315030 and 9211720. These publications
are incorporated by reference.
BRIEF DESCRIPTION OF DRAWINGS
[0004] Non-limiting examples will now be described with reference
to the accompanying drawings, in which:
[0005] FIG. 1 is an example of a printing system;
[0006] FIG. 2 is an example of a replaceable print apparatus
component;
[0007] FIG. 3 shows an example of a print apparatus;
[0008] FIGS. 4A, 4B, 4C, 4D and 4E show examples of logic circuitry
packages and processing circuitry;
[0009] FIG. 5 is an example of a method which may be carried out by
a logic circuitry package;
[0010] FIG. 6 is a further example of a method which may be carried
out by a logic circuitry package;
[0011] FIG. 7 shows an example of a method which may be carried out
for example by processing circuitry;
[0012] FIG. 8 shows an example arrangement of replaceable print
apparatus components in a print apparatus;
[0013] FIG. 9 shows an example of a replaceable print apparatus
component;
[0014] FIG. 10 is an example of a method of validating a print
apparatus component;
[0015] FIG. 11 is a further example of a method of validating a
print apparatus component;
[0016] FIG. 12 shows another example of a method of validation;
[0017] FIG. 13A shows an example arrangement of a fluid level
sensor;
[0018] FIG. 13B shows an example of a perspective view of a print
cartridge
[0019] FIG. 14 shows an example of a logic circuitry package;
[0020] FIG. 15 shows a further example of a logic circuitry
package;
[0021] FIGS. 16 to 18 show example methods of calibrating
sensors;
[0022] FIGS. 19A and 19B show example methods of reading
sensors;
[0023] FIG. 20A shows an example fluid level sensor and FIGS. 20B
and 20C shows examples of data acquired from a fluid level sensor;
and
[0024] FIG. 21A shows an example pressure event sensor and FIG. 21B
shows examples of data acquired from a pressure event sensor.
DETAILED DESCRIPTION
[0025] Some examples of applications described herein are in the
context of print apparatus. However, not all the examples are
limited to such applications, and at least some of the principles
set out herein may be used in other contexts.
[0026] The contents of other applications and patents cited in this
disclosure are incorporated by reference.
[0027] In certain examples, Inter-integrated Circuit (I.sup.2C, or
I2C, which notation is adopted herein) protocol allows at least one
`master` integrated circuit (IC) to communicate with at least one
`slave` IC, for example via a bus. I2C, and other communications
protocols, communicate data according to a clock period. For
example, a voltage signal may be generated, where the value of the
voltage is associated with data. For example, a voltage value above
x may indicate a logic "1" whereas a voltage value below x volts
may indicate a logic "0", where x is a predetermined numerical
value. By generating an appropriate voltage in each of a series of
clock periods, data can be communicated via a bus or another
communication link.
[0028] Certain example print material containers have slave logic
that utilizes I2C communications, although in other examples, other
forms of digital or analogue communications could also be used. In
the example of I2C communication, a master IC may generally be
provided as part of the print apparatus (which may be referred to
as the `host`) and a replaceable print apparatus component would
comprise a `slave` IC, although this need not be the case in all
examples. There may be a plurality of slave ICs connected to an I2C
communication link or bus (for example, containers of different
colors of print agent). The slave IC(s) may comprise a processor to
perform data operations before responding to requests from logic
circuitry of the print system.
[0029] Communications between print apparatus and replaceable print
apparatus components installed in the apparatus (and/or the
respective logic circuitry thereof) may facilitate various
functions.
[0030] Logic circuitry within a print apparatus may receive
information from logic circuitry associated with a replaceable
print apparatus component via a communications interface, and/or
may send commands to the replaceable print apparatus component
logic circuitry, which may comprise commands to write data to a
memory associated therewith, or to read data therefrom.
[0031] This disclosure may refer to print apparatus components,
which may include replaceable print apparatus components. Certain
print apparatus components may include a reservoir holding print
agent or print material. In this disclosure print material and
print agent mean the same thing and are intended to encompass
different example print materials including ink, toner particles,
liquid toner, three-dimensional printing agents (including
stimulators and inhibitors), three-dimensional printing build
material, three-dimensional print powder.
[0032] For example, the identity, functionality and/or status of a
replaceable print apparatus component and/or the logic circuitry
associated therewith may be communicated to logic circuitry of a
print apparatus via a communications interface. For example, a
print agent container logic circuit may be configured to
communicate an identity. For example, the identity may be stored on
the logic circuit to facilitate the checking thereof by a
compatible print apparatus logic circuit, wherein in different
examples the identity may be in the form of a product serial
number, another cartridge number, a brand name, a signature or bit
indicating an authenticity, etc. In certain examples of this
disclosure, multiple functions or logic circuits may be associated
with a single logic circuit package of a single print apparatus
component whereby multiple corresponding identities may be stored
on and/or read from the logic circuit package. For example, the
logic circuitry of the print apparatus component may store print
apparatus component characteristics data, for example comprising
data representative of at least one characteristic of a print
material container, for example print material identifying
characteristics, such as, total volume, initial fill volume and/or
fill proportion (see for example EP patent publication No.
0941856); color such as cyan, magenta, yellow or black; color data
including compressed or non-compressed color maps or portions
thereof (see for example international patent application
publication No. WO2015/016860); data to reconstruct colour maps
such as recipes (see for example international patent application
publication No. WO2016/028272); etc. For example, the print
material characteristics may be configured to enhance a
functionality or output with respect to a print apparatus in which
it is installed. In a further example, a status, such as print
material level-related data (e.g. a fill level) or other sensed
(e.g. dynamic) property, may be provided via a communications
interface, for example such that a print apparatus may generate an
indication of the fill level to a user. In some examples, a
validation process may be carried out by a print apparatus. An
example of a cryptographically authenticated communication scheme
is explained in US patent publication 9619663. For example, the
print apparatus may verify that a print agent container originates
from an authorized source, so as to ensure the quality thereof (for
example, performing an authentication thereof). Examples of logic
circuits of replaceable components that are configured to respond
to authentication requests are US patent publication No. 9619663,
US patent publication No. 9561662 and/or US patent publication No.
9893893.
[0033] In certain examples of this disclosure, a validation process
may include an integrity check to ensure that the replaceable print
apparatus component and/or the logic circuitry associated therewith
is functioning as expected, for example that communicated identity
or identities, print material characteristics and status are as
expected. The validation process may further comprise requesting
sensor information such that logic circuitry of a print apparatus
component can check that this sensor data complies with expected
parameters.
[0034] Examples of sensors and sensor arrays are disclosed in prior
international patent application publications WO2017/074342,
WO2017/184147, and WO2018/022038. These or other sensor types, or
other arrangements that simulate signal outputs similar to these
sensor arrays, could be used in accordance with this
disclosure.
[0035] In turn, instructions to perform tasks may be sent to logic
circuitry of a print apparatus component from logic circuitry
associated with a print apparatus via the communications
interface.
[0036] In at least some of the examples described below, a logic
circuitry package is described. The logic circuitry package may be
associated with a replaceable print apparatus component, for
example being internally or externally affixed thereto, for example
at least partially within the housing, and is adapted to
communicate data with a print apparatus controller via a bus
provided as part of the print apparatus.
[0037] A `logic circuitry package` as the term is used herein
refers to one or more logic circuits that may be interconnected or
communicatively linked to each other. Where more than one logic
circuit is provided, these may be encapsulated as a single unit, or
may be separately encapsulated, or not encapsulated, or some
combination thereof. The package may be arranged or provided on a
single substrate or a plurality of substrates. In some examples the
package may be directly affixed to a cartridge wall. In some
examples, the package may comprise an interface, for example
comprising pads or pins. The package interface may be intended to
connect to a communication interface of the print apparatus
component that in turn connects to a print apparatus logic circuit,
or the package interface may connect directly to the print
apparatus logic circuit. Example packages may be configured to
communicate via a serial bus interface.
[0038] In some examples, each logic circuitry package is provided
with at least one processor and memory. In one example, the logic
circuitry package may be, or may function as, a microcontroller or
secure microcontroller. In use, the logic circuitry package may be
adhered to or integrated with the replaceable print apparatus
component. A logic circuitry package may alternatively be referred
to as a logic circuitry assembly, or simply as logic circuitry or
processing circuitry.
[0039] In some examples, the logic circuitry package may respond to
various types of requests (or commands) from a host (e.g. a print
apparatus). A first type of request may comprise a request for
data, for example identification and/or authentication information.
A second type of request from a host may be a request to perform a
physical action, such as performing at least one measurement. A
third type of request may be a request for a data processing
action. There may be additional types or requests.
[0040] In some examples, there may be more than one address
associated with a particular logic circuitry package, which is used
to address communications sent over a bus to identify the logic
circuitry package which is the target of a communication (and
therefore, in some examples, with a replaceable print apparatus
component). In some examples, different requests are handled by
different logic circuits of the package. In some examples, the
different logic circuits may be associated with different
addresses.
[0041] In at least some examples, a plurality of such logic
circuitry packages (each of which may be associated with a
different replaceable print apparatus component) may be connected
to an I2C bus. In some examples, at least one address of the logic
circuitry package may be an I2C compatible address (herein after,
an I2C address), for example in accordance with an I2C protocol, to
facilitate directing communications between master to slaves in
accordance with the I2C protocol. In other examples, other forms of
digital and/or analogue communication can be used.
[0042] FIG. 1 is an example of a printing system 100. The printing
system 100 comprises a print apparatus 102 in communication with
logic circuitry associated with a replaceable print apparatus
component 104 via a communications link 106. Although for clarity,
the replaceable print apparatus component 104 is shown as external
to the print apparatus 102, in some examples, the replaceable print
apparatus component 104 may be housed within the print apparatus.
While a particular type of 2D print apparatus 102 is shown, a
different type of 2D print apparatus or a 3D print apparatus may
instead be provided.
[0043] The replaceable print apparatus component 104 may comprise,
for example a print material container or cartridge (which, again,
could be a build material container for 3D printing, a liquid or
dry toner container for 2D printing, or a liquid print agent
container for 2D or 3D printing), which may in some examples
comprise a print head or other dispensing or transfer component.
The replaceable print apparatus component 104 may for example
contain a consumable resource of the print apparatus 102, or a
component which is likely to have a lifespan which is less (in some
examples, considerably less) than that of the print apparatus 102.
Moreover, while a single replaceable print apparatus component 104
is shown in this example, in other examples, there may be a
plurality of replaceable print apparatus components, for example
comprising print agent containers of different colors, print heads
(which may be integral to the containers), or the like. In other
examples the print apparatus components 104 could comprise service
components, for example to be replaced by service personnel,
examples of which could include print heads, toner process
cartridges or logic circuit package by itself to adhere to
corresponding print apparatus component and communicate to a
compatible print apparatus logic circuit.
[0044] In some examples, the communications link 106 may comprise
an I2C capable or compatible bus (herein after, an I2C bus).
[0045] FIG. 2 shows an example of a replaceable print apparatus
component 200, which may provide the replaceable print apparatus
component 104 of FIG. 1. The replaceable print apparatus component
200 comprises a data interface 202 and a logic circuitry package
204. In use of the replaceable print apparatus component 200, the
logic circuitry package 204 decodes data received via the data
interface 202. The logic circuitry may perform other functions as
set out below. The data interface 202 may comprise an I2C or other
interface. In certain examples the data interface 202 may be part
of the same package as the logic circuitry package 204.
[0046] In some examples, the logic circuitry package 204 may be
further configured to encode data for transmission via the data
interface 202. In some examples, there may be more than one data
interface 202 provided.
[0047] In some examples, the logic circuitry package 204 may be
arranged to act as a `slave` in I2C communications.
[0048] FIG. 3 shows an example of a print apparatus 300. The print
apparatus 300 may provide the print apparatus 102 of FIG. 1. The
print apparatus 300 may serve as a host for replaceable components.
The print apparatus 300 comprises an interface 302 for
communicating with a replaceable print apparatus component and a
controller 304. The controller 304 comprises logic circuitry. In
some examples, the interface 302 is an I2C interface.
[0049] In some examples, the controller 304 may be configured to
act as a host, or a master, in I2C communications. The controller
304 may generate and send commands to at least one replaceable
print apparatus component 200, and may receive and decode responses
received therefrom. In other examples the controller 304 may
communicate with the logic circuitry package 204 using any form of
digital or analogue communication.
[0050] The print apparatus 102, 300 and replaceable print apparatus
component 104, 200, and/or the logic circuitry thereof, may be
manufactured and/or sold separately. In an example, a user may
acquire a print apparatus 102, 300 and retain the apparatus 102,
300 for a number of years, whereas a plurality of replaceable print
apparatus components 104, 200 may be purchased in those years, for
example as print agent is used in creating a printed output.
Therefore, there may be at least a degree of forwards and/or
backwards compatibility between print apparatus 102, 300 and
replaceable print apparatus components 104, 200. In many cases,
this compatibility may be provided by the print apparatus 102, 300
as the replaceable print apparatus components 104, 200 may be
relatively resource constrained in terms of their processing and/or
memory capacity.
[0051] FIG. 4A shows an example of a logic circuitry package 400a,
which may for example provide the logic circuitry package 204
described in relation to FIG. 2. The logic circuitry package 400a
may be associated with, or in some examples affixed to and/or be
incorporated at least partially within, a replaceable print
apparatus component 200.
[0052] In some examples, the logic circuitry package 400a is
addressable via a first address and comprises a first logic circuit
402a, wherein the first address is an I2C address for the first
logic circuit 402a. In some examples, the first address may be
configurable. In other examples, the first address is a fixed
address, e.g. "hard-wired", intended to remain the same address
during the lifetime of the first logic circuit 402a. The first
address may be associated with the logic circuitry package 400a at
and during the connection with a print apparatus logic circuit
(e.g. a controller 304), outside of the time periods that are
associated with a second address, as will be set out below. In
example systems where a plurality of replaceable print apparatus
components are to be connected to a single print apparatus, there
may be a corresponding plurality of different first addresses. In
certain examples, the first addresses can be considered standard
I2C address for logic circuitry packages 400a or replaceable print
components.
[0053] In some examples, the logic circuitry package 400a is also
addressable via a second address. For example, the second address
may be associated with different logic functions and/or, at least
partially, with different data than the first address. In some
examples, the second address may be associated with a different
hardware logic circuit or a different virtual device than the first
address.
[0054] In some examples, the second address may be configurable.
The second address may be an initial and/or default second address
at the start of a communication session via the second address and
may be reconfigured to a different second address after the start
of the session. In some examples, the second address may be used
for the duration of the communication session, the logic circuitry
package 400a may be configured to set the second address to a
default or initial address at the end of the session, or at or
before the beginning of a new session. Communications in such a
communication session may be directed to the second address and
between communication sessions may be directed to the first
address, whereby the print apparatus logic circuit 304 may verify,
for example, different identities, characteristics and/or status
through these different communication sessions via different
addresses. In examples where the end of a communication session via
the second address is associated with a loss of power to at least
part of the logic circuit as is further set out below, this loss of
power may cause the second `temporary` address to be discarded (for
example, the second address may be held in volatile memory, whereas
the initial or default address may be held in persistent memory).
Therefore a `new` or `temporary` second address may be set each
time after the corresponding communications session is started
(although in some cases the `new` or `temporary` second address may
have been previously used in relation to the logic circuitry).
[0055] In other examples the logic circuit package 400a may not set
itself back to the initial second address for starting each
corresponding communication session. Rather, it may allow for
configuring the second address at each corresponding communication
session, without switching to the initial or default second
address.
[0056] In other words, the second address may be configured to be
an initial second address at the start of a time period during
which the communication session is to take place. The logic
circuitry package 400a may be configured to reconfigure its second
address to a temporary address in response to a command sent to the
initial second address and including that temporary address during
that time period. The logic circuitry package 400a may then be
effectively reset such that upon receiving a subsequent command
indicative of the task and time period sent to the first address,
the logic circuitry package 400a is configured to have the same
initial second address.
[0057] In some examples, the initial and/or default second address
of different logic circuitry packages 204, 400a, for example
associated with different print material types (such as different
colours or agents) and compatible with the same print apparatus
logic circuit 304, may be the same. However, for each communication
session with the second address, each logic circuitry package 400a
may be temporarily associated with a different temporary address,
which may be set as the second address for each communication
session. In certain examples, a random temporary second address can
be used each time, in some examples with the condition that each
enabled second address on a common I2C bus at a particular instant
is different from the other enabled addresses. In some examples a
`random` second address may be a second address which is selected
from a predetermined pool of possible second addresses, which may,
in some examples, be stored on the print apparatus. The temporary
address may be generated by the print apparatus logic circuit 304
for each connected logic circuitry package 400a and communicated
through said command.
[0058] In some examples, the logic circuitry package 400a may
comprise a memory to store the second address (in some examples in
a volatile manner). In some examples, the memory may comprise a
programmable address memory register for this purpose.
[0059] In some examples, the package 400a is configured such that,
in response to a first command indicative of a first time period
sent to the first address (and in some examples a task), the
package 400a may respond in various ways. In some examples, the
package 400a is configured such that it is accessible via at least
one second address for the duration of the time period.
Alternatively or additionally, in some examples, the package may
perform a task, which may be the task specified in the first
command. In other examples, the package may perform a different
task.
[0060] The first command may, for example, be sent by a host such
as a print apparatus in which the logic circuitry package 400a (or
an associated replaceable print apparatus component) is installed.
As set out in greater detail below, the task may comprise a
monitoring task, for example, monitoring a timer (and in some
examples, monitoring the time period). In other examples, the task
may comprise a computational task, such as performing a
mathematical challenge. In some examples, the task may comprise
activating a second address and/or effectively deactivating the
first address for communication purposes (or may comprise
performance of actions which result in the activation or enabling
of a second address and/or effectively deactivating or disabling of
the first address). In some examples, activating or enabling a
second address may comprise setting (e.g. writing, re-writing or
changing), or triggering the setting of, a second address (for
example, a temporary second address), for example by writing the
second address in a portion of memory which is indicative of an
address of the logic circuitry package 400a.
[0061] Where a task is specified, the task and/or time period may
be specified explicitly in the first command, or may be inferred by
the logic circuitry package 400a by reference to a lookup table or
the like. In one example, the first command may for example
comprise mode data and time data. For example, a first data field,
which may be sent as part of a serial data package, may comprise a
mode field. This may for example be around one or a few bits or
bytes in size. A second data field, which may be sent as part of
the serial data packet of the first data field in some examples,
may comprise a `dwell time` data field. For example, this may be
around two or a few bits or bytes in size and may specify a time
period, for example in milliseconds.
[0062] In some examples, the package 400a is configured so as to be
inaccessible via the second address (the default or temporary
second address or any address other the first address) for a second
time period preceding (in some examples, immediately preceding) the
first time period and/or for a third time period following (in some
examples, immediately following) the first time period. In some
examples, the first logic circuit 402a is to ignore I2C traffic
sent to the first address (or any address other than a currently
active second address) for the duration of the time period. In
other words, the package 400a may respond to commands directed to
the first address and not to commands directed to the second
address outside the first time period; and may respond to commands
directed to the second address and not to commands directed to the
first address during the first time period. The term `ignore` as
used herein with respect to data sent on the bus may comprise any
or any combination of not receiving (in some examples, not reading
the data into a memory), not acting upon (for example, not
following a command or instruction) and/or not responding (i.e. not
providing an acknowledgement, and/or not responding with requested
data). For example, `ignoring` I2C traffic sent to the first
address may be defined as the logic circuitry package 400a not
responding to communications directed to the first address (or any
address other than a currently active second address as perceivable
by the print apparatus logic circuit 304).
[0063] Causing the first logic circuit 402a to `ignore` (or
otherwise not respond to) I2C traffic sent to the first address for
the duration of the time period for which the second address is
activated or in use allows the first and second addresses to be
entirely independent of one another. For example, the first address
may be I2C compliant whereas a second address may be of any format,
including in some examples a non-I2C compliant format. In addition,
if the first address is effectively disabled for the duration of
the time period, consideration need not be made as to any response
to a command which the package 400a may consider to be addressed to
the first address. For example, the first address may be
represented by a particular bit sequence and, if there is a
possibility that the first address may be recognized when the
package is not to be addressed using the first address, precautions
may be taken such that this identifying bit sequence is avoided
when the package is not to be addressed using the first address.
The likelihood of this event could increase in the instance where
communication is established via different temporary second
addresses of respective different logic circuitry packages within a
single time period over the same serial bus. If these situations
are not managed correctly, indeterminate or unexpected behaviour
may be seen. However, if the first address is effectively disabled
during the time period, there need be no such consideration or
precautions, and commands which could otherwise be inadvertently
received and interpreted by the package 400a as having been
received by the first address will not be received as the first
address is effectively inactivated. The reverse may also be true
(i.e. commands which may be inadvertently taken to be addressed to
any second address will not be received by the package 400a outside
the time period if that address is effectively disabled outside the
time period).
[0064] In some examples, the first and the second addresses may be
of different lengths. For example, the first address may be a
10-bit address and the second address may be a 7-bit address. In
other examples, the first and second address may be of the same
length, for example both comprising a 7-bit or 10-bit address. In
certain examples the first and the default second address are
hardwired, while the second address allows for reconfiguration to
the temporary address, as explained above. In other examples the
first and second address may be programmed.
[0065] In some examples, the first logic circuit 402a is to perform
a task, which may be the task specified in the command received,
for the duration of the time period. However, in other examples,
for example to allow for increased compatibility, the first logic
circuit 402a may not perform the specified task (for example, if it
is unable to do so, or it is unnecessary to do so to keep the first
logic circuit 402a `busy`, as described below).
[0066] In some examples, the first logic circuit 402a may in effect
not respond to (i.e., ignore) requests sent to the first address as
a result of performing a task, which may be a task specified in the
first command. In some examples, the task may at least
substantially consume the processing capacity of the first logic
circuit 402a. For example, the task may comprise monitoring a timer
in such a way that the processing capacity of the first logic
circuit 402a is substantially dedicated to that task. In other
examples, the processing capacity may be substantially dedicated to
performing a computational task, such as an arithmetical task. In a
simple example, the first logic circuit 402a may be tasked with
calculating a value such as pi. This task may be, according to
present understanding, unlimited in the sense that a processor
could continue calculating pi to further decimal places for an
infinite amount of time. Therefore, the performance of this task to
completion exceeds any likely time period specified in the first
command. For example, such time periods may be, in some examples,
in the order of seconds or tens of seconds. If the first logic
circuit is dedicated to the task of calculating pi/monitoring a
timer until the time period has passed, it may not also be
monitoring traffic sent thereto via a communications bus or the
like. Therefore, even if the communications were sent to the first
address, these would be ignored. It may be noted that certain I2C
slave devices will generally ignore a bus while performing any kind
of processing. However, the processing specified herein is
associated with the time period. It is noted that, given that the
logic circuit package is not responsive to communications to its
first address for the time for which the second address is
activated, in some examples, the (temporary) second address could
be the same as the first address whereby the desired function
corresponding to that second address may still be achieved.
However, as explained before, in other examples, the second address
is different to the first address.
[0067] It will be appreciated that the task of calculating pi is
merely one example of a task which may generally exceed a time
period specified in a first command. Other examples of
computational tasks having a completion time which is likely to
exceed the time period may be selected, for example based on the
length of the time period under consideration. For example, if the
time period is to last for no longer than 3 seconds, a processing
task which will exceed 3 seconds in duration may be performed (and,
in some examples, instructed in the first command). Moreover, in
other examples, as noted above, the task may comprise monitoring a
time period.
[0068] In other examples, the logic circuitry packages 400a may be
configured to, in response to such a first command including the
task and time period, not respond to communications directed to its
first address, not necessarily by performing a processing task but
effectively by being programmed not to respond.
[0069] In some examples, the package 400a is configured to provide
a first set of responses, or to operate in a first mode, in
response to instructions sent to the first address and to provide a
second set of responses, or to operate in a second mode, in
response to instructions sent to the second address. In other
words, the address may trigger different functions provided by the
package 400a. In some examples, at least one response of the first
set of responses is output in response to commands sent to the
first address and not in response to commands sent to the second
address and at least one response of the second set of responses is
output in response to commands sent to the second address and not
in response to commands sent to the first address. In some
examples, the first set of responses may be cryptographically
authenticated (i.e. accompanied by a message authentication code
generated using a base key, or otherwise cryptographically
`signed`, and/or encrypted, see for example US patent publication
No. 9619663) and the second set of responses is not
cryptographically authenticated. In some examples, the second set
of responses may relate to sensor data and the first set of
responses may not relate to sensor data. In some examples, messages
may be accompanied by a session key identifier. For example an
identity of a logic circuit of the package 400a could be
communicated in the first and the second set of responses, whereby
it is cryptographically authenticated in the first set but not in
the second set. This may allow the package 400a to provide two
distinct functions. Data may be output from an output data buffer
of the package 400a.
[0070] In some examples, the package 400a may be configured to
participate in a first validation process using I2C communications
sent to the first address, and to participate in a second
validation process using communications sent to the second address.
As noted above, the second address may be a reconfigurable address,
and in some examples may be reconfigured after the first validation
process has been carried out. In some examples, the first
validation process may comprise an exchange of encrypted or
authenticable messages, wherein the messages are encrypted and/or
signed based on a base key stored in the package, which may be a
secret key (or based on a secret base key) that corresponds to a
secret key stored or held in the print apparatus. In some examples,
the second validation process may comprise an integrity check, in
which the package 400a may return requested data values such that a
host apparatus can verify that these data values meet predetermined
criteria.
[0071] In examples set out above, the addresses used to communicate
with the circuitry package 400a have been described. Further
communication may be directed to memory addresses to be used to
request information associated with these memory addresses. The
memory addresses may have a different configuration than the first
and second address of the logic circuitry package 400a. For
example, a host apparatus may request that a particular memory
register is read out onto the bus by including the memory address
in a read command. In other words, a host apparatus may have a
knowledge and/or control of the arrangement of a memory. For
example, there may be a plurality of memory registers and
corresponding memory addresses associated with the second address.
A particular register may be associated with a value, which may be
static or reconfigurable. The host apparatus may request that the
register be read out onto the bus by identifying that register
using the memory address. In some examples, the registers may
comprise any or any combination of address register(s), parameter
register(s) (for example to store gain and/or offset parameters),
sensor identification register(s) (which may store an indication of
a type of sensor), sensor reading register(s) (which may store
values read or determined using a sensor), sensor number
register(s) (which may store a number or count of sensors), version
identity register(s), memory register(s) to store a count of clock
cycles, memory register(s) to store a value indicative of a
read/write history of the logic circuitry, or other registers.
[0072] In some examples, the package 400a may be configured to
respond to a data request (for example, a sensor data request)
received from the print apparatus by returning a first response,
then, following receipt of a calibration (e.g. conversion)
parameter (and, in some examples a subsequent data request), return
a second response which is different from the first response. In
some examples, this functionality may be provided from a second
logic circuit. In some examples, the received calibration parameter
may be used to adjust the second response, or may otherwise be used
in determining a second response which is different to the first
response. In some examples the print apparatus logic circuit may
send a new calibration parameter if the first response does not
meet predetermined criteria (for example, is outside of a
predetermined range), and the second response may need to be
adjusted on this basis, by the package 400a. This may for example
comprise part of a calibration routine, in which response data may
need to be set to be within predetermined limits, for example so as
to avoid `range clipping`, in which a data reading is capped at a
high or a low end of a range when a parameter reaches a threshold,
even though the parameter being measured may continue to change
beyond the threshold. Such a routine may continue with responses
being adjusted until a response and/or a set of responses which
meets predetermined criteria is seen. Examples of calibration are
discussed in greater detail below.
[0073] In some examples, the package 400a may be configured to
receive a data request, determine whether the request is for data
indicative of a print material level sensor or for data indicative
of a pressurisation (e.g. a pressure change) event, and to respond
with a data response. In some examples, the data request may
comprise a `read` command in which the acquired data is read from a
memory of the package 400a. In some examples, the data request may
comprise at least two commands. For example, a first command may
comprise a `write` command, which triggers the acquisition of
sensor data by the package 400a, and the acquired data is stored in
a memory of the package 400a. In an example, the first command may
provide information allowing a sensor type/sensor cell to be
identified, and may trigger (in some examples on receipt of a
specific "conversion" command, but in other examples in response to
the first command) a sequence of events to carry out sensing,
execute an ND conversion to store the conversion value into a
memory location, which may be predetermined (for example,
comprising a sensor data register). The sensing may be carried out
using parameters (e.g. electrical test parameters, heating
parameters, timing of measurements, etc.) which may also be stored
in a memory (in some examples, in separate memory registers),
and/or may be provided with the command. The ND conversion may be
carried out using parameters which may also be stored in a memory
(in some examples, in one or more memory register(s)). As discussed
below in greater detail, the conversion parameters and/or the
sensing parameters may be configured in a calibration operation. A
second command may comprise a `read` command in which the acquired
data is read from a memory of the package 400a.
[0074] Characteristics of the data reading may be different for
different types of sensor data requested. For example, the data
response may comprise one or more values in a first range when the
request is for data indicative of a print material level and may
comprise one or more values in a second range when the request is
for data indicative of a pressurisation event. In some examples,
the values may comprise count values. In some examples, to obtain
the response values in the respective first and second range, first
operational parameters for the corresponding sensor type may have
been (over) written to respective memory fields.
[0075] In some examples, a data response may comprise, in total, a
first number of data readings when the request is for data of a
print material level sensor and a second number of data readings
when the request is for data indicative of a pressurisation event.
Such a response may be provided over a series of data exchanges
with processing circuitry of the print apparatus in which the
package 400a is installed. For example, each data reading of the
data response may be provided in response to a read request of a
plurality of read requests received from logic circuitry of a print
apparatus, and each read request may follow a write request from
logic circuitry of a print apparatus, wherein receipt of the read
request may trigger the acquisition of a data reading.
[0076] In some examples, the number of data readings returned for a
particular sensor is less than the number of sensor cells or
sensing elements of that sensor. This may allow a print apparatus
in which the package 400a is installed to query an appropriate
number of sensor cells without excessive bandwidth. For example, it
may be that there are on the order of 100 or 150 sensor cells which
form part of an ink level sensor in an ink cartridge. The print
material level sensor in such an example may return 100 or 150 data
readings (which may for example be requested one after another as
outlined above). However, there may be on the order of 30 or 40
sensor cells which form part of a pressure sensor, for example
comprising strain sensors or the like. Thus the pressure change
sensor in such an example may return 30 or 40 data readings (which
may for example be requested one after another). In some examples,
a subset of the available sensor element or cells may be queried.
For example, there may be around 100 or more sensor elements/cells
of a particular sensor type, and only around 30 or the set may be
queried and provide readings, for example to reduce sampling times.
For example, it may be that, over the duration of a pressurisation
event (or any other temporary or transitory state during which
sensor readings are to be acquired), there may be time to query
some, but not all, of the sensors/sensor cells.
[0077] In some examples, there may be additional data requests,
such as any or any combination of print material temperature, an
ambient temperature, a `crack detection` sensor request, and the
like.
[0078] FIG. 4B shows another example of a logic circuitry package
400b. In this example, the package 400b comprises a first logic
circuit 402b, in this example comprising a first timer 404a, and a
second logic circuit 406a, in this example comprising a second
timer 404b. While in this example, each of the first and second
logic circuits 402b, 406a comprises its own timer 404, in other
examples, they may share a timer, or reference at least one
external timer. In a further example, the first logic circuit 402b
and the second logic circuit 406a are linked by a dedicated signal
path 408.
[0079] In one example, the logic circuitry package 400b may receive
a first command comprising two data fields. A first data field is a
one byte data field setting a requested mode of operation. For
example, there may be a plurality of predefined modes, such as a
first mode, in which the logic circuitry package 400b is to ignore
data traffic sent to the first address (for example, while
performing a task), and a second mode in which the logic circuitry
package 400b is to ignore data traffic sent to the first address
and to transmit an enable signal to the second logic circuit 406a,
as is further set out below.
[0080] The first command may comprise additional fields, such as an
address field and/or a request for acknowledgement.
[0081] The logic circuitry package 400b is configured to process
the first command. If the first command cannot be complied with
(for example, a command parameter is of an invalid length or value,
or it is not possible to enable the second logic circuit 406a), the
logic circuitry package 400b may generate an error code and output
this to a communication link to be returned to host logic
circuitry, for example in the print apparatus.
[0082] If however, the first command is validly received and can be
complied with, the logic circuitry package 400b measures the
duration of the time period included in the first command, for
example utilising the timer 404a. In some examples, the timer 404a
may comprise a digital "clock tree". In other examples, the timer
404a may comprise an RC circuit, a ring oscillator, or some other
form of oscillator or timer. In this example, in response to
receiving a valid first command, the first logic circuit 402b
enables the second logic circuit 406a and effectively disables the
first address, for example by tasking the first logic circuit 402b
with a processing task as described above. In some examples,
enabling the second logic circuit 406a comprises sending, by the
first logic circuit 402b, an activation signal to the second logic
circuit 406a. In other words, in this example, the logic circuitry
package 400b is configured such that the second logic circuit 406a
is selectively enabled by the first logic circuit 402b.
[0083] In this example, the second logic circuit 406a is enabled by
the first logic circuit 402b sending a signal via a signal path
408, which may or may not be a dedicated signal path 408, that is,
dedicated to enable the second logic circuit 406a. In one example,
the first logic circuit 402b may have a dedicated contact pin or
pad connected to the signal path 408, which links the first logic
circuit 402b and the second logic circuit 406a. In a particular
example, the dedicated contact pin or pad may be a General Purpose
Input/Output (a GPIO) pin of the first logic circuit 402b. The
contact pin/pad may serve as an enablement contact of the second
logic circuit 406a.
[0084] The voltage of the signal path 408 may be driven to be high
in order to enable the second logic circuit 406a. In some examples,
such a signal may be present for substantially the duration of the
first time period, for example, starting following receipt of the
first command and may cease at the end of the first time period. As
noted above, the enablement may be triggered by a data field in the
command. In other examples, the second logic circuit may be
selectively enabled/disabled, for example for the duration of the
time period, in another way.
[0085] In some examples, such a contact pad or pin is provided in a
manner so as to be generally inaccessible from the exterior of a
replaceable print apparatus component. For example, it may be
relatively distant from an interface and/or may be fully enclosed
by a housing. This may be useful in ensuring that it is only
triggered via the first logic circuit 402b.
[0086] In this example, the second logic circuit 406a is
addressable via at least one second address. In some examples, when
the second logic circuit 406a is activated or enabled, it may have
an initial, or default, second address, which may be an I2C address
or have some other address format. The second logic circuit 406a
may receive instructions from a master or host logic circuitry to
change the initial address to a temporary second address. In some
examples, the temporary second address may be an address which is
selected by the master or host logic circuitry. This may allow the
second logic circuit 406a to be provided in one of a plurality of
packages 400 on the same I2C bus which, at least initially, share
the same initial second address. This shared, default, address may
later be set to a specific temporary address by the print apparatus
logic circuit, thereby allowing the plurality of packages to have
different second addresses during their temporary use, facilitating
communications to each individual package. At the same time,
providing the same initial second address may have manufacturing or
testing advantages.
[0087] In some examples, the second logic circuit 406a may comprise
a memory. The memory may comprise a programmable address register
to store the initial and/or temporary second address (in some
examples in a volatile manner). In some examples, the second
address may be set following, and/or by executing, an I2C write
command. In some examples, the second address may be settable when
the enablement signal is present or high, but not when it is absent
or low. The second address may be set to a default address when an
enablement signal is removed and/or on restoration of enablement of
the second logic circuit 406a. For example, each time the enable
signal over the signal path 408 is low, the second logic circuit
406a, or the relevant part(s) thereof, may be reset. The default
address may be set when the second logic circuit 406a, or the
relevant part(s) thereof, is switched out-of-reset. In some
examples the default address is a 7-bit or 10-bit identification
value. In some examples, the default address and the temporary
second address may be written in turn to a single, common, address
register.
[0088] In some examples, the address of the second logic circuit
406a may be rewritten at any time at which it is enabled. In some
examples, when connected to the bus, the second logic circuit 406a
may be in a low current state except when it is in an enabled
state.
[0089] In some examples, the second logic circuit 406a may comprise
a power-on reset (POR) device. This may comprise an electronic
device which detects the power applied to the second logic circuit
406a and generates a reset impulse that goes to the entire second
logic circuit 406a placing it into a known state. Such a POR device
may be of particular utility in testing the package 400b prior to
installation.
[0090] In some examples, a plurality of further logic circuits may
be `chained` together, with further pins (which may be GPIO pins)
or the like. In some examples, once the second address has been
written (i.e. the logic circuit has an address which is different
to its default address), it may activate an `out` pin or pad, and
an `in` pin or pad of the next logic circuit in the chain (if one
exists) thereby be driven high and the logic circuit may be
enabled. Such a further logic circuit(s) may function as described
in relation to the second logic circuitry 406a. Such further logic
circuits may have the same default address as the second logic
circuit 406a in some examples. There is no absolute limit as to how
many logic circuits can be serially chained and accessed in this
way, however there may be a practical limitation in a given
implementation based on the series resistance on the bus lines, the
number of Slave IDs, and the like.
[0091] In one example, the first logic circuit 402b is configured
to generate an enablement signal that may be an active low
asynchronous reset signal. In some examples, when this signal is
removed (or is driven to a logic 0), the second logic circuit 406a
may immediately cease operations. For example, data transfers may
immediately cease, and a default state (which may be a sleep state
and/or a low current state) may be assumed by the second logic
circuit 406a. In some examples, memories such as registers may
revert to an initialised state (for example, a default address may
comprise an initialised state of an address register).
[0092] In an example in which an I2C bus is used for communications
with the package 400b, the first logic circuit 402b and the second
logic circuit 406a may be connected to the same I2C bus. As noted
above, an additional connection, for example provided between GPIO
pins of the first logic circuit 402b and the second logic circuit
406a may be selectively enabled following receipt of a dedicated
command. For example, the first logic circuit 402b may drive a
dedicated GPIO pin to be high for a time period specified in a
command (whereas by default the pin may be in a low state). For the
duration of this time period, the first logic circuit 402b may not
acknowledge (`NAK`) any attempts to communicate using the first
address. At the end of the specified time period, the dedicated
contact pin may be returned to the `low` state, and the first logic
circuit 402b may be receptive to communications on the I2C bus sent
to the first address once again. However, while the contact pin is
driven to be high, the second logic circuit 406a may be enabled,
and receptive to communications on the I2C bus.
[0093] It may be noted that, by sharing I2C contacts between the
first logic circuit 402b and the second logic circuit 406a,
electrical interconnect cost is small. Additionally, if the second
logic circuit is selectively powered only for the duration of the
time period, it may be less susceptible to electrochemical wear. In
addition, this may allow multiple packages comprising respective
first logic circuits 402b and second logic circuits 406a to be
provided on the same serial I2C bus, where the second logic
circuits 406a may (at least initially) share an address, which may
in turn reduce manufacturing and deployment complexities.
[0094] In some examples, as outlined above, the logic circuitry
package 400b comprises a first operational mode in which it
responds to communication sent to the first address and not any
second address and a second operational mode in which it responds
to communications sent to a second address (e.g. the second address
currently in use, and in some examples, currently stored in a
dedicated register of the second logic circuit 406a) and not the
first address.
[0095] In the example illustrated in FIG. 4b, the second logic
circuit 406a comprises a first array 410 of cells and at least one
second cell 412 or second array of second cells. The first cells
416 a-f, 414 a-f and the at least one second cell 412 can comprise
resistors. The first cells 416 a-f, 414 a-f and the at least one
second cell 412 can comprise sensors. In one example the first cell
array 410 comprises a print material level sensor and the at least
one second cell 412 comprises another sensor and/or other sensor
array.
[0096] In this example, the first cell array 410 comprises a sensor
configured to detect a print material level of a print supply,
which may in some examples be a solid but in examples described
herein is a liquid, for example, an ink or other liquid print
agent. The first cell array 410 may comprise a series of
temperature sensors (e.g. cells 414a-f) and a series of heating
elements (e.g. cells 416a-f), for example similar in structure and
function as compared to the level sensor arrays described in
WO2017/074342, WO2017/184147, and WO2018/022038. In this example,
the resistance of a resistor cell 414 is linked to its temperature.
The heater cells 416 may be used to heat the sensor cells 414
directly or indirectly using a medium. The subsequent behaviour of
the sensor cells 414 depends on the medium in which they are
submerged, for example whether they are in liquid (or in some
examples, encased in a solid medium) or in air. Those which are
submerged in liquid/encased may generally heat more slowly and lose
heat quicker than those which are in air because the liquid or
solid may conduct heat away from the resistor cells 414 better than
air. Therefore, a liquid level may be determined based on which of
the resistor cells 414 are exposed to the air, and this may be
determined based on a reading of their resistance following (at
least the start of) a heat pulse provided by the associated heater
cell 416.
[0097] In some examples each sensor cell 414 and heater cell 416
are stacked with one being directly on top of the other. The heat
generated by each heater cell 416 may be substantially spatially
contained within the heater element layout perimeter, so that heat
delivery is substantially confined to the sensor cell 414 stacked
directly above the heater cell 416. In some examples, each sensor
cell 414 may be arranged between an associated heater cell 416 and
the fluid/air interface.
[0098] In this example, the second cell array 412 comprises a
plurality of different cells that may have a different function
such as different sensing function(s). For example, the first and
second cell array 410, 412 may include different resistor types.
Different cells arrays 410, 412 for different functions may be
provided in the second logic circuit 406a.
[0099] In one example, the second cell(s) 412 may comprise at least
one sensor to detect a change in pressure and/or a pneumatic action
applied by the print apparatus to a print component to which the
package 400b is to be mounted. For example such at least one sensor
to detect a change in pressure and/or pneumatic action may comprise
strain sensing cell(s). In some examples, the strain sensing cells
may comprise piezo-resistive cells. In one example, the strain
sensing cells may be arranged across a surface of a chamber for
containing print materials. For example, an ink cartridge may be
pressurized in order to dispense ink in a predetermined manner. In
order to test that such pressurization is correctly operational, a
test may be carried out using strain gauges arranged across the
surface of the chamber. This may comprise a `hyperinflation` event,
in which the cartridge is subjected to a pressure which is greater
than that used in normal operation when dispensing ink and the
like. In the event of a pressurization, it may be expected that the
chamber will `bulge out`. Thus strain sensors arranged across the
surface may be expected to show a change in strain. Some examples
of strain sensors are discussed in greater detail below.
[0100] The sensors 410, 412 may be read, and/or parameters thereof
(and/or parameters of conversion apparatus associated therewith)
may be calibrated. In some examples, calibration and/or reading of
the sensors 410, 412 takes place when the second logic circuit 406a
is enabled and/or following the setting of a temporary second
address.
[0101] FIG. 4C shows an example of how a first logic circuit 402c
and a second logic circuit 406b of a logic circuitry package 400c,
which may have any of the attributes of the circuits/packages
described above, may connect to an I2C bus and to each other. As is
shown in the Figure, each of the circuits 402c, 406b has four pads
(or pins) 418a-d connecting to the Power, Ground, Clock and Data
lines of an I2C bus. In another example, four common connection
pads are used to connect both logic circuits 402c, 406b to four
corresponding connection pads of the print apparatus controller
interface. It is noted that in some examples, instead of four
connection pads, there may be fewer connection pads. For example,
power may be harvested from the clock pad; an internal clock may be
provided; or the package could be grounded through another ground
circuit; so that, one or more of the pads may be omitted or made
redundant. Hence, in different examples, the package could use only
two or three interface pads and/or could include "dummy" pads.
[0102] Each of the circuits 402c, 406b has a contact pin 420, which
are connected by a common signal line 422. The contact pin 420 of
the second circuit serves as an enablement contact thereof.
[0103] In this example, each of the first logic circuit 402c and
the second logic circuit 406b comprises a memory 423a, 423b.
[0104] The memory 423a of the first logic circuit 402c stores
information comprising cryptographic values (for example, a
cryptographic key and/or a seed value from which a key may be
derived) and identification data and/or status data of the
associated replaceable print apparatus component. In some examples
the memory 423a may store data representing characteristics of the
print material, for example any, any part, or any combination of
its type, color, color map, recipe, batch number, age, et
cetera.
[0105] The memory 423b of the second logic circuit 406b comprises a
programmable address register to contain an initial address of the
second logic circuit 406b when the second logic circuit 406b is
first enabled and to subsequently contain a further (temporary)
second address (in some examples in a volatile manner). The
further, e.g. temporary, second address may be programmed into the
second address register after the second logic circuit 406b is
enabled, and may be effectively erased or replaced at the end of an
enablement period. In some examples, the memory 423b may further
comprise programmable registers to store any, or any combination of
a read/write history data, cell (e.g. resistor or sensor) count
data, Analogue to Digital converter data (ADC and/or DAC), and a
clock count, in a volatile or non-volatile manner. Use of such data
is described in greater detail below. Certain characteristics, such
as cell count or ADC or DAC characteristics, could be derivable
from the second logic circuit instead of being stored as separate
data on the memory. Such registers may be addressable using memory
addresses.
[0106] In one example, the memory 423b of the second logic circuit
406b stores any or any combination of an address, for example the
second I2C address; an identification in the form of a revision ID;
and the index number of the last cell (which may be the number of
cells less one, as indices may start from 0), for example for each
of different cell arrays or for multiple different cell arrays if
they have the same number of cells.
[0107] In use of the second logic circuit 406b, in some operational
states, the memory 423b of the second logic circuit 406 may store
any or any combination of timer control data, which may enable a
timer of the second circuit, and/or enable frequency dithering
therein in the case of some timers such as ring oscillators; a
dither control data value (to indicate a dither direction and/or
value); and a timer sample test trigger value (to trigger a test of
the timer by sampling the timer relative to clock cycles measurable
by the second logic circuit 406b). In some examples, the memory
423b of the second logic circuit 406b may be configured to store
calibration parameters associated with sensors, for example control
parameters, calibration parameters, heating time or strength
(power) parameters, gain parameters or the like. These parameters
may be set to a default value at the beginning of a time period
(for example a time period during which the second logic circuit
406b is enabled) and/or may be written and/or overwritten during
the time period.
[0108] While the memories 423a, 423b are shown as separate memories
here, they could be combined as a shared memory resource, or
divided in some other way. The memories 423a, 423b may comprise a
single or multiple memory devices, and may comprise any or any
combination of volatile memory e.g. DRAM, SRAM, registers, etc. and
non-volatile memory e.g. ROM, EEPROM, Flash, EPROM, memristor,
etc.
[0109] While one package 400c is shown in FIG. 4C, there may be a
plurality of packages with a similar or a different configuration
attached to the bus.
[0110] FIG. 4D shows an example of processing circuitry 424 which
is for use with a print material container. For example, the
processing circuitry 424 may be affixed or integral thereto. As
already mentioned, the processing circuitry 424 may comprise any of
the features of, or be the same as, any other logic circuitry
package of this disclosure.
[0111] In this example, the processing circuitry 424 comprises a
memory 426 and a first logic circuit 402d which enables a read
operation from memory 426. The processing circuitry 424 is
accessible via an interface bus of a print apparatus in which the
print material container is installed and is associated with a
first address and at least one second address. The bus may be an
I2C bus. The first address may be an I2C address of the first logic
circuit 402d. The first logic circuit 402d may have any of the
attributes of the other examples circuits/packages described in
this disclosure.
[0112] The first logic circuit 402d is adapted to participate in
authentication of the print materials container by a print
apparatus in which the container is installed. For example, this
may comprise a cryptographic process such as any kind of
cryptographically authenticated communication or message exchange,
for example based on an encryption key stored in the memory 426,
and which can be used in conjunction with information stored in the
printer. In some examples, a printer may store a version of a key
which is compatible with a number of different print material
containers to provide the basis of a `shared secret`. In some
examples, authentication of a print material container may be
carried out based on such a shared secret. In some examples, the
first logic circuit 402d may participate in a message to derive a
session key with the print apparatus and messages may be signed
using a message authentication code based on such a session key.
Examples of logic circuits configured to cryptographically
authenticate messages in accordance with this paragraph are
described in the earlier mentioned US patent publication No.
9619663.
[0113] In some examples, the memory 426 may store data comprising:
identification data and read/write history data. In some examples,
the memory 426 further comprises cell count data (e.g. sensor count
data) and clock count data. Clock count data may indicate a clock
speed of a first and/or second timer 404a, 404b (i.e. a timer
associated with the first logic circuit or the second logic
circuit). In some examples, at least a portion of the memory 426 is
associated with functions of a second logic circuit, such as a
second logic circuit 406a as described in relation to FIG. 4B
above. In some examples, at least a portion of the data stored on
the memory 426 is to be communicated in response to commands
received via the second address. In some examples, the memory 426
comprises a programmable address register or memory field to store
a second address of the processing circuitry (in some examples in a
volatile manner). The first logic circuit 402d may enable read
operation from the memory 426 and/or may perform processing
tasks.
[0114] Other examples of first logic circuits 402 described herein
may be adapted to participate in authentication processes in a
similar manner.
[0115] The memory 426 may, for example, comprise data representing
characteristics of the print material, for example any or any
combination of its type, color, batch number, age, et cetera. The
memory 426 may, for example, comprise data to be communicated in
response to commands received via the first address. In some
examples, the memory 426 may store parameters associated with
reading and/or calibrating sensors, for example control parameters,
conversion parameters or the like. The memory may comprise a
non-volatile memory. The first logic circuit 402d to enable read
operations from the memory 426 and perform processing tasks. In
other words, in some examples, the memory 426 may functionally be
associated with the first logic circuit 402d.
[0116] In some examples, the processing circuitry 424 is configured
such that, following receipt of the first command indicative of a
task and a first time period sent to the first logic circuit 402d
via the first address, the processing circuitry 424 is accessible
by at least one second address for a duration of the first time
period. Alternatively or additionally, the processing circuitry 424
may be configured such that in response to a first command
indicative of a task and a first time period sent to the first
logic circuit 402d addressed using the first address, the
processing circuitry 424 is to disregard (e.g. `ignore` or `not
respond to`) I2C traffic sent to the first address for
substantially the duration of the time period as measured by a
timer of the processing circuitry 424 (for example a timer 404a, b
as described above). In some examples, the processing circuitry may
additionally perform a task, which may be the task specified in the
first command. The term `disregard` or `ignore` as used herein with
respect to data sent on the bus may comprise any or any combination
of not receiving (in some examples, not reading the data into a
memory), not acting upon (for example, not following a command or
instruction) and/or not responding (i.e. not providing an
acknowledgement, and/or not responding with requested data).
[0117] The processing circuitry 424 may have any of the attributes
of the logic circuitry packages 400 described herein. In
particular, the processing circuitry 424 may further comprise a
second logic circuit wherein the second logic circuit is accessible
via the second address. In some examples the second logic circuit
may comprise at least one sensor which is readable by a print
apparatus in which the print material container is installed via
the second address. In some examples, such a sensor may comprise
any of a print materials level sensor, a strain sensor, a pressure
sensor or the like.
[0118] The processing circuitry 424 may have a first validation
function, triggered by messages sent to a first address on an I2C
bus and a second validation function, triggered by messages sent to
a second address on the I2C bus.
[0119] FIG. 4E shows another example of a first logic circuit 402e
and second logic circuit 406c of a logic circuitry package 400d,
which may have any of the attributes of the circuits/packages of
the same names described herein, which may connect to an I2C bus
via respective interfaces 428a, 428b and to each other. In one
example the respective interfaces 428a, 428b are connected to the
same contact pad array, with only one data pad for both logic
circuits 402e, 406c, connected to the same serial I2C bus, see for
example FIGS. 13A and 13B. In other words, in some examples,
communications addressed to the first and the second address are
received via the same data pad.
[0120] In this example, the first logic circuit 402e comprises a
microcontroller 430, a memory 432 and a timer 434. The
microcontroller 430 may be a secure microcontroller or customized
integrated circuitry adapted to function as a microcontroller,
secure or non-secure.
[0121] In this example, the second logic circuit 406c comprises a
transmit/receive module 436 which receives a clock signal and a
data signal from a bus to which the package 400d is connected, data
registers 438, a multiplexer 440, a digital controller 442, an
analogue bias and analogue to digital converter 444, at least one
sensor or cell array 446 (which may in some examples comprise a
level sensor with one or multiple arrays of resistor elements), and
a power-on reset (POR) device 448. The POR device 448 may be used
to allow operation of the second logic circuit 406c without use of
a contact pin 420.
[0122] The analogue bias and analogue to digital converter 444
receives readings from the sensor array(s) 446 and from external
sensors. For example, a current may be provided to a sensing
resistor and the resultant voltage may be converted to a digital
value. That digital value may be stored in a register and read out
(i.e. transmitted as serial data bits, or as a `bitstream`) over
the I2C bus. The analogue to digital converter 444 may utilise
parameters, for example, gain and/or offset parameters, which may
be stored in the registers 438. In some examples, the gain and/or
offset parameter may be set or amended in a calibration operation.
In some examples, the registers 438 may additionally store control
parameters for the sensors 446, 450, 452 and 454. For example,
these may specify heating powers and/or durations, electrical
parameters such as voltage and/or currents, other time parameters
such as the length of a test period and the like.
[0123] In this example, there are different additional single
sensors, including for example at least one of an ambient
temperature sensor 450, a crack detector 452 and/or a fluid
temperature sensor 454. These may sense, respectively, an ambient
temperature, a structural integrity of a die on which the logic
circuitry is provided and a fluid temperature.
[0124] FIG. 5 shows an example of a method which may be carried out
by processing circuitry, for example by a logic circuitry package
such as the logic circuitry packages 400a-d described above, or by
the processing circuitry 424 described in relation to FIG. 4D,
and/or by processing circuitry provided on a replaceable print
apparatus component, for example a consumable printing materials
container.
[0125] Block 502 comprises receiving a first command indicative of
a task and a first time period which is sent to a first address of
processing circuitry. Block 504 comprises enabling, by the
processing circuitry, access to the processing circuitry by at
least one second address of the processing circuitry for the
duration of the time period.
[0126] FIG. 6 shows one example of the method of block 504 in
greater detail. In this example, a first and second logic circuit
are provided, each respectively associated with the first and at
least one second address as described above with reference to FIG.
4B.
[0127] Block 602 comprises activating the second logic circuit. As
described above, this may comprise a first logic circuit sending or
transmitting an activation signal to a second logic circuit to
activate the second logic circuit, for example via a dedicated
signal path. In this example, activating the second logic circuit
allows access to the processing circuitry using the at least one
second address, for example using an initial or default second
address. In some examples, following activation, the second logic
circuit may be caused to set a new or temporary second address, for
example to replace an initial or default address of the second
logic circuit. In some examples, the temporary address may be set
for the duration of a communication session.
[0128] Block 604 comprises disabling access to the processing
circuitry via the first address (i.e. using communications
addressed to the first address) for the duration of the time period
by causing the first logic circuit to perform a processing task (in
some examples, the processing task specified in the command
received in block 502) for the duration of the time period. In
other examples, the first address may be effectively disabled by
preventing transmission of responses to messages sent to the first
address. Block 606 comprises monitoring, by the processing
circuitry, the duration of the time period using a timer of the
processing circuitry. In some examples, monitoring the duration of
the time period using the timer may itself comprise the processing
task.
[0129] After the time period has expired, the method proceeds with
block 608, which comprises deactivating the second logic circuit.
For example, this may comprise removing an activation signal by the
first logic circuit. Access to the processing circuitry via the
second address may therefore be disabled after the duration of the
time period. For example, the second logic circuit may be
de-energized or placed in a sleep mode by the removal of the
signal.
[0130] In examples where the end of a communication session is
associated with a loss of power to at least part of the logic
circuit, this loss of power may cause the second address to be
discarded (for example, the second address may be held in volatile
memory, whereas the initial or default address may be hardwired or
held in persistent memory). After reset, the second address may
again be set to the default or initial address before the beginning
of a new session. In some examples, the initial or default address
may be held in persistent memory and may be restored to a register
of the second logic circuit when the second logic circuit is
enabled. Therefore a `new` second address may be set each time a
communications session is started (although in some cases the `new`
second address may have previously been used in relation to the
logic circuitry).
[0131] As set out in greater detail elsewhere herein, during the
period of activation, the second logic circuit may provide
services, for example cell or sensor readings or the like. However,
in other examples, the second logic circuit may for example provide
an output such as activating a light or sound (for example, the
second logic circuit may control a light source or speaker or some
other apparatus), may receive data (for example, may comprise a
memory which is to store a data file), and/or may provide some
other type of output or service.
[0132] FIG. 7 shows an example of a method which may be carried out
for example by processing circuitry 424 or by a package 400a-d as
described above. The method comprises, in block 702, receiving a
first command indicative of a processing task and a first time
period sent to a first address of processing circuitry via a
communications bus, for example an I2C bus.
[0133] Block 704 comprises starting a timer of the processing
circuitry. In other examples, a timer may be monitored rather than
started. For example, an initial count of the timer may be recorded
and an increase in the count may be monitored.
[0134] Block 706 comprises performing, by the processing circuitry,
a processing task and block 708 comprises disregarding traffic sent
to the first address. In some examples, disregarding the I2C
traffic may be as a result of performing the task specified in the
command, or another task. The task may comprise monitoring a timer.
In other examples, the task may comprise a computational task, such
as working to solve a mathematical challenge.
[0135] Block 708 may continue until the time period expires, as
monitored using the timer.
[0136] The method may comprise any of the features described above
in relation to a tasks and/or to disregarding (e.g. `ignoring` or
simply `not responding to`) traffic. The method may be carried out
using processing circuitry which is associated with, or provided
on, a printing material container and/or a replaceable print
apparatus component.
[0137] In some examples, as described above, the method may
comprise, for the duration of the time period, responding, by the
processing circuitry, to I2C traffic sent to a second address of
the processing circuitry. In some examples, the first address is
associated with the first logic circuit of the processing circuitry
and the second address is associated with the second logic circuit
of the processing circuitry. In some examples, where first and
second logic circuits are provided, the first logic circuit may
perform the processing task and/or may send an activation signal to
the second logic circuit, for example via a dedicated signal path,
for the duration of the time period. In some examples, the second
logic circuit may be deactivated by ceasing the activation
signal.
[0138] FIG. 8 schematically shows an arrangement in which a
plurality of replaceable print apparatus components 802a-d are
provided in a print apparatus 804.
[0139] Each of the replaceable print apparatus components 802a-d is
associated with a logic circuitry package 806a-d, which may be a
logic circuitry package 400a-d as described above. The print
apparatus 804 comprises host logic circuitry 808. The host logic
circuitry 808 and the logic circuitry packages 806 are in
communication via a common I2C bus 810. In one mode of operation,
each of the logic circuitry packages 806 has a different first
address. Therefore, each of the logic circuitry packages 806 (and
by extension, each of the replaceable print apparatus components)
may be addressed uniquely by the host print apparatus 804.
[0140] In an example, a first command may be sent to a particular
one of the replaceable print apparatus component logic circuitry
packages 806, i.e. being addressed using the unique first address
for that logic circuitry package, instructing it to enable its (at
least one) second address for a corresponding `first command` time
period. Therefore, that replaceable print apparatus component 802
may, for example, enable at least one second address and/or, in
some examples, its associated functions. In some examples this
results in enabling a second logic circuit as described above. For
example, the addressed logic circuitry package 806 may ignore (e.g.
not acknowledge and/or not respond to) I2C traffic sent to the
first address of that logic circuitry package 806 for the duration
of the first command time period, for example in response to the
same command or a separate command. The other print apparatus
components 802 may also be sent a second command resulting in them
ignoring I2C traffic sent to their first addresses for the duration
of a `second command` time period. As noted above, when there are
no other slave devices `listening` to the I2C bus, restrictions as
to the form and content of messages sent over the I2C bus may be
reduced. Therefore, in this way, all of the first addresses may be
effectively disabled whilst only one second address is in
communication with the I2C bus 810. In other examples, more than
one packages may be addressable by respective different addresses
at the same time. In some examples, a first command may also result
in an addressed component/package ignoring I2C traffic sent to
their first addresses for the duration of the first command time
period, and/or a second command may also result in an addressed
component/package being accessible via at least one second
address.
[0141] In some examples, the logic circuitry package(s) 806 may
perform a processing task, which may be a processing task as
specified in a command, so as to `keep busy` and ignore I2C traffic
sent to the first address for the duration of the specified time
period. As noted above, this may comprise a computing task or a
monitoring task, for example monitoring a timer.
[0142] Thus, the logic circuitry packages 806 may be configured to
have a first response to a first command, which results in a second
address of that package being enabled for the duration of the first
command time period, and a second response to a second command,
which results in the package ignoring I2C traffic sent to the first
address (for example by performing a processing task such as
monitoring a timer and/or carrying out a computational task which
absorbs processing capacity) for the duration of the second command
time period. In other words, each of the logic circuitry packages
806 may be enabled to carry out either of the methods of FIGS. 5
and/or 7, depending on the nature of the command received.
[0143] In some examples, logic circuitry packages 806 may be
configured to respond to one or a series of sensor read requests by
providing corresponding count values within a range of count
values. In some examples, this may comprise responding to a first
sensor read request by providing a count value within a first
sub-range of the range of count values and responding to a second
sensor read request by providing a count value within a second
sub-range of the range of count values. In some examples, the logic
circuitry packages 806 may be configured to respond to each read
request of a set of first sensor read requests and to each read
request of a set of second sensor read requests. The read requests
may for example be sent from the print apparatus logic circuitry
808.
[0144] To consider a particular example, a host device such as a
print apparatus 804 in this example wishing to communicate with a
particular logic circuitry package 806 via its second address--in
this example logic circuitry package 806a--may issue commands so as
to instruct the other logic circuitry packages 806b-d to act in a
manner which results in them ignoring traffic on the bus 810. This
may comprise the logic circuitry 808 serially sending three
commands addressed to a unique address of each of the other logic
circuitry packages 806b-d, each command specifying a first mode of
operation and a time period. The first mode of operation may result
in traffic on the bus being ignored. Next, the logic circuitry 808
may send a dedicated command to the target logic circuitry package
806a via its first address, the command specifying a second mode of
operation and a time period. The second mode of operation may
comprise an instruction resulting in traffic on the bus 810 sent to
a first address being ignored and enablement of a second address.
The first command time period and the second command time period
for which traffic is ignored by different logic circuit packets 806
may be specified to overlap with one another, in some examples
bearing in the mind the delay with which instructions will be
received.
[0145] The host logic circuitry may then communicate with the
selected logic circuitry package 806a via its second address for
the duration of the time period. During this time period, as in
some examples no other devices are `listening` to the I2C bus, any
communication protocol (including in some examples a non-I2C
compliant protocol) may be used for communicating with the selected
logic circuitry package 806a via its second address.
[0146] Of course, this is only one example. In other examples, some
or all packages may be accessible via a second address
concurrently, or a mixture of first and second addresses of
respective packages may be accessible.
[0147] FIG. 9 shows an example of a replaceable print apparatus
component 802 which includes an I2C compatible logic circuitry
package 900, which may comprise any of the attributes of the
packages 400a-d or of the circuitry 424 described in relation to
FIGS. 4A-E, and which may in some examples be configured to carry
out any of the methods described herein. The package in this
example comprises an I2C interface 902 including a data contact 904
to communicate via an I2C bus of a host printer.
[0148] The package in this example comprises a memory comprising
data representing print liquid characteristics, and the data is
retrievable and updatable via the data contact 904. The package 900
is configured to, in response to a read request received from a
host apparatus via a first I2C address (i.e. the read request is
addressed using the first address), transmit data including said
data representing print liquid characteristics over the bus and via
the data contact 904. Different replaceable print apparatus
components 802 may be associated with memories which may store
different print liquid characteristics.
[0149] The package 900 is further configured such that, in response
to a command indicative of a task and a first time period received
via the first address, the package transmits data for the duration
of the time period over the same bus and data contact in response
to (and in some examples, only in response to) received commands
which are addressed to at least one second address, different than
the first address, and after the end of the time period, again
transmit data over the same bus and data contact in response to
(and in some examples, only in response to) received commands which
are addressed to the first address.
[0150] In some examples, the at least one different address
includes a default second address and a further or temporary second
address wherein the package 900 is configured to, in response to a
received command which is addressed to the default second address,
reconfigure the address to be the temporary second address and/or
to respond to (and in some examples, only in response to)
subsequent commands sent to the temporary second address until the
end of the time period. Such responses may be sent over the same
bus and the single data contact 904.
[0151] In some examples, the package 900 may be configured to
respond to a data request (for example a sensor data request)
received from the print apparatus by returning a first response,
then, following receipt of a calibration parameter (and, in some
examples, a subsequent data request), return a second response
which is different from the first response. In some examples, this
functionality may be provided from a second logic circuit. This may
for example comprise part of a calibration routine as described in
further detail elsewhere in this disclosure.
[0152] In some examples, the package 900 may be configured to
receive a data request, determine whether the request is for data
indicative of a print material level sensor or for data indicative
of a pressurisation event, and to respond with a data response. In
some examples, the data readings may be requested one after another
for example to provide a first number of data readings when the
requests are for data of a print material level sensor and a second
number of data readings when the requests are for data indicative
of a pressurisation event. In some examples, the data response may
comprise one or more values in a first range when the request is
for data of a print material level sensor and may comprise one or
more values in a second range when the request is for data
indicative of a pressurisation event. In some examples, the values
may comprise count values.
[0153] In some examples, the data request may comprise at least two
separate commands: a first command may effectively trigger the
acquisition of data by a sensor, for example comprising a `write`
command, which may identify a sensor cell and/or sensor type. The
sensor type may for example be a level sensor, ambient temperature
sensor, fluid temperature sensor, pressure sensor, strain gauge,
crack detector or the like. A second command may comprise a `read`
command, for example requesting that a memory register
corresponding to a memory address provided in the read command is
read out.
[0154] The replaceable print apparatus component 802 may be
provided as one of a plurality of print apparatus components, the
memories of which store different print material characteristics.
The package of each of the plurality of replaceable print apparatus
components may be configured to, in response to a command
indicative of the task and the first time period received via
respective first addresses, transmit data responses to received
commands which are addressed to the same respective default
addresses.
[0155] In some examples, the package 900 is configured to transmit,
in response to indicated received commands which are addressed to
the first address outside the time period, data that is
authenticated, for example, cryptographically authenticated, for
example using a secret key and accompanied by a message
authentication code. During the time period, however, data which is
not authenticated may be transmitted in response to received
commands which are addressed to the at least one different
address.
[0156] FIG. 10 describes a method of validating a print apparatus
component using logic circuitry associated therewith. In some
examples, the logic circuitry may be a logic circuitry package
404a-d, 900 and/or processing apparatus 424 as described above.
[0157] For example, in validating a print apparatus component, it
may be intended to verify that a print agent container originates
from an authorized source, so as to ensure the quality thereof (for
example, by performing an authentication thereof). In some
examples, the validation process may include an integrity check to
ensure that the replaceable print apparatus component and/or the
logic circuitry associated therewith is functioning as expected.
This may comprise requesting sensor information such that logic
circuitry of a print apparatus component can check that this sensor
data complies with expected parameters.
[0158] The method comprises, in block 1002, responding to a first
validation request sent via an I2C bus to a first address
associated with the logic circuitry with a first validation
response. Block 1004 comprises responding to a second validation
request sent via the I2C bus to a second address associated with
the logic circuitry with a second validation response.
[0159] In some examples, the first validation response is a
cryptographically authenticated response. For example, this may
make use of a shared secret and/or use a cryptographic key. In some
examples, the cryptographic response may comprise at least one
`signed` message, for example a message accompanied by a message
authentication code, or may comprise an encrypted response. In some
examples, the second validation response comprises an unencrypted
response(s), or unsigned response(s). In some examples, most or all
responses to validation requests sent to the first address are
cryptographically signed using a key stored on the logic circuit,
while no responses to validation requests sent to the second
address are cryptographically signed. This may allow processing
resources used to provide responses to commands sent to the second
address to be reduced.
[0160] FIG. 11 describes one example of block 1004 in greater
detail. In this example, the second validation request comprises a
request for an indication of the clock speed of a timer of the
logic circuitry (in some examples, a request for a clock speed of
the second timer 404b, or more generally a timer associated with
the second logic circuit). The method comprises, in block 1102,
determining a clock speed of the logic circuitry relative to a
frequency of another system clock or cycle signal measurable by the
logic circuitry. Block 1104 comprises determining a second
validation response based on the relative clock speed. This may,
for example, allow a time period to be set by a host apparatus in
the context of a timer provided with the logic circuitry. In some
examples, the clock speed of a timer of the logic circuitry itself
may be measured in order to determine the validation response. For
example, the number of clock cycles of the timer within a
predetermined number of other clock signals/measurable cycles may
be determined, and, in some examples, an indication of the result
may be provided as the validation response. In some examples, a
clock speed may effectively be determined by comparing a known
clock speed of a timer of the logic circuitry with the clock speed.
In some examples, the validation response may comprise a selection
of a value (e.g. a clock count) held in a memory indicating the
clock speed of the logic circuitry relative to a system
clock/measurable cycle. As has been noted above, in one example the
response may be based on the clock speed of an internal timer of
the second logic circuit, which may be a second timer in addition
to a first timer of the first logic circuit.
[0161] To consider one example of such a method, the logic
circuitry may comprise a number of registers. In one example, a
register may record the number of outputs of a timer of a logic
circuitry package (in some examples, a timer associated with a
second logic circuit) over a set number of cycles detectable by the
logic circuitry. For example, over 8 detectable cycles, there may
be, say, 120 cycles recorded using the internal timer of the logic
circuitry package. This may be recorded in one or more registers.
In such example, the value "120" could be recorded on a register or
memory, which may be read and verified by the print apparatus logic
circuit, wherein verification may for example comprise comparing
the value with an expected value. In one example, this relative
clock speed value may be represented by the clock count that is
mentioned in examples of this disclosure. In another example, the
clock count can relate to an absolute clock speed. The clock speed
can be measured and compared with a stored clock count. In this
disclosure, the stored clock count may include any value
representing the relative clock speed or clock count including a
reference value or a range.
[0162] In some examples, a system clock may be set to take account
of a speed of the timer. In some examples, a system clock may be
driven by a ring oscillator of the second logic circuit as
described above. The second logic circuit may comprise multiple
timers such as both a SAR clock (for the analogue to digital
converter) and a system clock.
[0163] FIG. 12 shows another example of a method of validation,
which may be a method of validating a print apparatus component
using logic circuitry associated therewith. In some examples, the
logic circuitry may be a logic circuitry package 404a-d, 900 and/or
processing apparatus 424 as described above.
[0164] In this example, the logic circuit package responds to a
first validation request directed to its first address with
cryptographically authenticated response(s) in block 1200. As part
of the first validation, any or any combination of a version
identity (i.e. revision ID) of (at least part of) the package; a
number cells per type; a print material level; a clock count; a
read/write history data and other identity and characteristics data
related to the second address may be included. In some examples,
identification data associated with a second logic circuit, such as
the version identity as described above, may be stored in a first
logic circuit. In some examples, the identification data may be
stored in both the first and the second logic circuits. In some
examples, after a second logic circuit has been enabled, as
described above, the method comprises in block 1202, receiving an
address setting signal, which is sent via the I2C bus to an initial
second address associated with logic circuitry. In some examples,
the address setting signal may be indicative of a temporary second
address. For example host logic circuitry (e.g. logic circuitry of
a print apparatus) may select and/or generate the temporary second
address, and transmit this to the logic circuitry associated with
the replaceable print apparatus component. In other examples, the
temporary second address may be selected in some other way, for
example based on data held in a memory of the logic circuitry.
Block 1204 comprises setting the second address as the address of
the logic circuitry. As noted above, in some examples, this may
comprise replacing a default address with a temporary address which
may be selected, in some examples, by a print apparatus.
[0165] In some examples, the temporary second address may be
retained for the duration of a communication period, and then the
address may revert to the initial address (which may therefore
provide a default address). In some examples, the initial address
is reinstated on the next occasion that the second logic circuit is
enabled.
[0166] The method continues in block 1206 by determining the second
validation response by reading a memory of logic circuitry to
provide an indication of version identity. This may be an
indication of the version of hardware, software and/or firmware
used in the logic circuitry package, for example in a second logic
circuit of the package. In some examples, this may be an indication
of the version of at least one sensor which may be provided as part
of the logic circuitry. The version identity (i.e. revision ID) of
the second validation may match the version identity of the first
validation.
[0167] For example, this may comprise providing one or more
`revision value`, which may be the content of one or more
registers. It may be the case that at least one, and in some
examples, each, die and/or subcomponent of the logic circuitry is
associated with a revision value which indicates the type or
version of hardware, and may allow a master I2C circuit to provide
more appropriate communications.
[0168] Assuming that the returned values meet predetermined
criteria (for example, an expected number of revision values is
returned and/or the revision value is recognised by a host print
apparatus, or has a valid format or the like), the method continues
in block 1208 by determining a further second validation response
by testing at least one component of the logic circuitry to return
a test result. While sensors may not be provided in association
with all logic circuitry (and/or a test thereof may not be
performed), in some examples, the second validation response may
comprise an actual test of any provided sensors or cells involved
in communications through the second address. For example, this may
comprise a test to indicate that a cell and/or a resistor is
responding as expected. For example, the test may include verifying
the absolute or relative clock speed, for example by comparing the
measured clock speed with a stored clock speed, as described above.
In some examples an expected value for the clock speed may be
determined based on the indication of version identity (e.g. the
`revision value`). For example, it may be determined that a
particular version of hardware is expected to have a particular
response value.
[0169] In some examples, the indication of version identity may be
used to set parameters for a sensor or sensor cell reading. For
example, a duration and/or power of a heat pulse, or an offset
and/or a gain setting of an analogue to digital converter, may be
set based on the indicated version identity. In other examples,
calibration of parameters may also or alternatively take place.
[0170] In block 1210 the method comprises determining a further
second validation response by reading a memory of logic circuitry
to provide an indication of the number of cells or sensors in at
least one sensor type. In some examples, the returned number of
this second validation should match a sensor count provided in the
first validation. For example, this may provide an indication of
the number of resistors in a fluid level sensor. In some examples,
there may be a plurality of values provided relating, for example,
to different sensor types. This validation feature may allow a
print apparatus to configure parameters for later reading of the
sensors. In addition, if this value is not an expected value, which
may be determined by matching values provided in the first and
second validations, it may result in the logic circuitry failing a
validation test. In some examples the expected value may be
determined based on the second validation response. For example, it
may be determined that a particular version of hardware is expected
to have a particular number of sensors.
[0171] In this example, a read and/or write status of at least part
of the logic circuitry, (in some examples, the read/write history
of a second logic circuit) is recorded in a memory thereof on an
ongoing basis, for example between actions associated with each
block of FIG. 12. In particular, in this example, a plurality of
indications of a read/write status is stored in a memory, each
being determined using a different predetermined algorithmic
function. Such algorithmic functions (which may be secret
algorithmic function(s), or based on secret data, wherein the
solution is also derivable based on a secret known by the print
apparatus in which the replaceable print apparatus component is to
be arranged) may be applied such that different read/write actions
result in a different value being stored. The algorithmic function
may include scrambling, e.g. signing the read/write history value,
which may be executed by hardwiring or written instructions on the
logic circuitry package. In some examples, the content of the read
and/or write may be considered by the algorithm such that the same
number of read/write operations may result in a different value
being associated with the history if the content of the read/write
operations differ. In some examples, the order of read/write
operations may also impact the value stored. The algorithm could be
stored or hardwired in the logic circuitry package, for example in
the second logic circuit. In some examples, the read/write history
status value can be used for data communication error checking. In
some examples, the logic circuitry package is configured to update
the read/write history after read/write events. For example, the
second logic circuit may be configured, for example hardwired, to
re-write the read/write history data portion after each respective
read or write action on the second logic circuit, wherein the
read/write history data portion may be re-written after or at each
read or write cycle. The read/write history data portion may be
updated after a read request from the print apparatus, a write
request from the print apparatus, or both. For example, the
updating may be based on an internal output buffer refresh, or it
may be based on a received instruction of the print apparatus
circuit. The second logic circuit may be hardwired to update the
read/write history data portion based on actions of the second
logic circuit. In an example, the logic circuitry package is
configured to not update the read/write history when reconfiguring
the second address to the temporary address. In an example, the
logic circuitry package is configured to update the read/write
history during the measured time period, after configuring the
second address to the temporary address. In yet another example the
print apparatus rewrites the read/write history data field.
[0172] In this example, therefore, the method further comprises
storing a plurality of indications of the read/write history status
of the logic circuitry and updating the stored indication with each
read/write request of the logic circuitry.
[0173] In block 1212, the method comprises determining a further
second validation response which comprises an indication of a read
and/or write history of the logic circuitry. The response may be
selected based on an indication provided in the request, such that
an expected value, associated with a particular algorithmic
function is selected and returned. The algorithmic function may be
stored or hardwired in the logic circuitry package, for example the
second logic circuit. The algorithmic functioning may include
signing the read/write history data. Providing a number of
different algorithmic functions may assist in increasing security
of the validation process.
[0174] In one example, the logic circuitry comprises at least one
register (e.g. read-only) that creates a value representing a
signature, i.e. that allows for decoding and checking by a print
apparatus that stores the data to decode the signature. A value
indicative of the read/write history may be stored therein and may
be updated when operations (reads/writes) occur within the logic
circuitry, and therefore provides an indication of a read and/or
write history of the logic circuitry. It may not be the case that
all actions result in the register being updated and there may be
at least one register access event that does not result in the
value being updated. The order of the read/writes may have an
effect on the values. As the host apparatus may keep its own
history of the reads and writes it requests of the logic circuitry,
it can verify the value against its own record to determine if the
read/writes are being performed and/or if the function to determine
the value is operating as expected.
[0175] In this example, while such methods may be thought of as
pseudo-cryptographic methods, as they may be based on a shared
secret, the second validation response may be provided without a
digital signature or message authentication code or session key or
session key identifier, nor may it qualify as cryptographically
authenticated communication, whereas the first validation response
may be provided with a digital signature, message authentication
code or session key and/or session key identifier and may qualify
as cryptographically authenticated communication. In one example,
the different validations may be associated with different logic
circuits that can be integrated in the package in a relatively
cost-efficient way without compromising system integrity.
[0176] In another example, a second validation response may
comprise an indication of crack sensor data. In some examples, a
crack sensor comprises a long `wire` of a conductor (in one
example, polysilicon) routed around the perimeter of a die
providing the logic circuitry that can be electrically tested. The
wire may be relatively fragile, so a crack in the die will likely
result in a break in the conductor. For example an intact sensor
may result in a read result of around 125-160 of a possible range
of 0-255. If a read result is outside this range, it is an
indication that mechanical damage has cracked the die and a
validation check may fail.
[0177] In some examples, the methods of any of FIGS. 10 to 12 may
be carried out in relation to replaceable print apparatus
components in which sensors are likely to contact printing fluids.
Such contact may mean that the sensors are liable to suffer damage
and therefore verifying that the sensors are acting as intended may
be particularly beneficial. However, the methods may also be
carried out in relation to other types of replaceable print
apparatus components.
[0178] In some examples if any validation response is not as
expected (or, in some examples, if a response and/or an
acknowledgement of a request is not received), a print apparatus
may determine that a replaceable print apparatus component has
failed a check, and, in some examples, may reject the replaceable
print apparatus component. In some examples, at least one operation
of the print apparatus may be prevented or altered as a result of a
replaceable print apparatus component failing a check.
[0179] In some examples, the validation responses may be provided
in time slices, with each test being carried out in a serial
manner.
[0180] FIG. 13A shows an example of a possible practical
arrangement of a second logic circuit embodied by a sensor assembly
1300 in association with a circuitry package 1302. The sensor
assembly 1300 may comprise a thin film stack and include at least
one sensor array such as a fluid level sensor array. The
arrangement has a high length:width aspect ratio (e.g. as measured
along a substrate surface), for example being around 0.2 mm in
width, for example less than 1 mm, 0.5 mm or 0.3 mm, and around 20
mm in length, for example more than 10 mm, leading to length:width
aspect ratios equal to or above approximately 20, 40, 60, 80 or
100:1. In an installed condition the length may be measured along
the height. The logic circuit in this example may have a thickness
of less than 1 mm, less than 0.5 mm or less than 0.3 mm, as
measured between the bottom of the (e.g. silicon) substrate and the
opposite outer surface. These dimensions mean that the individual
cells or sensors are small. The sensor assembly 1300 may be
provided on a relatively rigid carrier 1304, which in this example
also carries Ground, Clock, Power and Data I2C bus contacts.
[0181] FIG. 13B shows a perspective view of a print cartridge 1312.
The print cartridge 1312 has a housing 1314 that has a width W less
than its height H and that has a length L or depth that is greater
than the height H. A print liquid output 1316 (in this example, a
print agent outlet provided on the underside of the cartridge
1312), an air input 1318 and a recess 1320 are provided in a front
face of the cartridge 1312. The recess 1320 extends across the top
of the cartridge 1312 and I2C bus contacts (i.e. pads) 1322 of a
logic circuitry package 1302 (for example, a logic circuitry
package 400a-d, 900 as described above) are provided at a side of
the recess 1320 against the inner wall of the side wall of the
housing 1314 adjacent the top and front the housing 1314. In this
example, the data contact is the lowest of the contacts 1322. In
this example, the logic circuitry package 1302 is provided against
the inner side of the side wall.
[0182] In some examples the logic circuitry package 1302 comprises
a sensor assembly as shown in FIG. 13A.
[0183] It will be appreciated that placing logic circuitry within a
print material cartridge may create challenges for the reliability
of the cartridge due to the risks that electrical shorts or damage
can occur to the logic circuitry during shipping and user handling,
or over the life of the product.
[0184] A damaged sensor may provide inaccurate measurements, and
result in inappropriate decisions by a print apparatus when
evaluating the measurements. Therefore, a method as set out in
relation to FIGS. 10 to 12 may be used to verify that
communications with the logic circuitry based on a specific
communication sequence provide expected results. This may validate
the operational health of the logic circuitry.
[0185] In other examples, a replaceable print apparatus component
includes a logic circuitry package of any of the examples described
herein, wherein the component further comprises a volume of liquid.
The component may have a height H that is greater than a width W
and a length L that is greater than the height, the width extending
between two sides. Interface pads of the package may be provided at
the inner side of one of the sides facing a cut-out for a data
interconnect to be inserted, the interface pads extending along a
height direction near the top and front of the component, and the
data pad being the bottom-most of the interface pads, the liquid
and air interface of the component being provided at the front on
the same vertical reference axis parallel to the height H direction
wherein the vertical axis is parallel to and distanced from the
axis that intersects the interface pads (I.e. the pads are
partially inset from the edge by a distance d). The rest of the
logic circuitry package may also be provided against the inner
side.
[0186] In some examples, the print cartridge comprises a print
material container comprising a validation circuitry package
comprising a memory, a contact array for connecting with a I2C bus
of a print apparatus, at least one timer, and circuitry to provide
a first validation function, triggered by messages sent to a first
address on an I2C bus; and a second validation function, triggered
by messages sent to a second address on the I2C bus.
[0187] In pre-existing print apparatus components such as print
cartridges, logic circuitry packages may consist of integrated
circuits sometimes referred to as microcontrollers or secure
microcontrollers. These integrated circuits are configured to
store, communicate and update status and characteristics of
corresponding print apparatus components, sometimes in a secure
manner. Said status may include a level of print material, for
example updated by the print apparatus after each print job and
based on drop count and/or page count. Basing the status on drop
count or page count implies an indirect way of measuring a
remaining print material level because it may be based on, e.g.,
global print statistics rather than the contents of the individual
print apparatus component. Consequently, the status or
characteristics of a print apparatus component, as stored and
reflected by its associated logic circuitry package could be wrong
or not reliable.
[0188] This disclosure addresses first example logic circuitry
packages adapted to enable connecting further sensor devices to a
print apparatus component, or including those sensor devices. This
disclosure also addresses other examples of logic circuitry
packages that are configured to be compatible with a print
apparatus logic circuit that is designed to be compatible with
(e.g. read, write and/or command) the first example logic circuitry
packages.
[0189] As said, different examples of this disclosure facilitate
different sub-devices in a circuit package of a replaceable print
component to communicate with a printer controller, for example in
addition to, or instead of, the afore mentioned
microcontroller-based integrated circuits alone, which are
typically not configured to directly measure certain components'
status.
[0190] In one example, the logic circuit package allows for a
relatively secure and reliable communication while controlling
costs and/or manufacturing. Certain examples of this disclosures
facilitate adding capabilities to (partly) existing communication
protocols in printers, such as the existing I2C busses that
communicate with integrated circuits on the print apparatus
components.
[0191] In one example, this disclosure explores inclusion of, for
example, lab-on-chip type, cell arrays (e.g. as part of "second
logic circuits") in print apparatus component logic circuitry
packages, which in one example may be implemented in conjunction
with existing print apparatus interface buses, for example in an
effort to control costs and reliability. As explained earlier,
examples of second logic circuits include thin, silicon-based,
sensor arrays. In one example these sensors do not use established
or standard digital data communication protocols such as I2C.
Rather they may rely on custom analogue signal communications. Some
of the examples of this disclosure involve the integration of such
memory arrays in logic circuitry packages of print apparatus
components.
[0192] FIG. 14 represents different specific examples of a logic
circuitry package including such sensor arrays.
[0193] FIG. 14 illustrates a logic circuitry package 1401 for a
replaceable print component to interface with a print apparatus
logic circuit through a single interface package and having a
second logic circuit 1405 with cell or sensor arrays. The logic
circuitry package 1401 may include a first logic circuit 1403 and a
second logic circuit 1405, although the sub-features that will be
described below could be provided in a single package without a
clear distinction between first and second logic circuit 1403,
1405. In fact, the illustrated logic circuitry package 1401 may
include some, not all, of the illustrated sub-components. The
illustrated sub-components have been addressed in other examples of
this disclosure. Some of the features are explained in relation to
the first and second validations. For a better understanding of
certain features of FIG. 14 reference is made to all the
publications cited in this disclosure, all of which pertain to the
present applicant.
[0194] The first logic circuit 1403 includes a first address
(indicated by a block 1402), which may be a first I2C address, and
which may be different than other packages of other components that
are to be connected to the same host apparatus at the same time.
The second logic circuit 1405 may include a second address
(indicated by block 1404) which, at least before or at enabling the
second logic circuit 1405, may be the same as other packages of
other components that are to be connected to the same host
apparatus at the same time. At or after enablement of the second
logic circuit 1405 the second address may be reconfigured, for
example to be different than other connected packages 1401.
[0195] The first logic circuit 1403 includes a memory 1407 and a
CPU (central processing unit) 1409. The memory 1407 may include a
signed and unsigned portion, for example depending on desired
security of a particular data feature, as desired by an OEM and/or
partly by available space of each signed or unsigned portion. The
memory 1407 may store at least one of characteristics, status and
identity data 1415, 1419/1437 associated with the replaceable print
component. The characteristics may include colour, print material
type, colour maps 1411, colour conversion recipes 1413, and other
characteristics. The identity 1415 could include a product number,
brand and/or any code to be associated with the identity of the
replaceable print apparatus component, for example for association
with a warranty of an OEM should that be necessary or for other
reasons. In certain examples, the identity or identities 1419/1437,
1415 may intentionally be left blank, for example when a third
party supplies other than the OEM the package 1401. The status may
include data for association with a relative or absolute print
material level 1427, for example based on at least one of page
count, drop count and/or based on a status of cells 1451, 1453,
1457, 1455 of the second logic circuit 1403, 1405. The first logic
circuit 1403 may further include a cryptographic key 1441 to
cryptographically authenticate messages, which messages may include
any of said status, characteristics and/or identity.
[0196] The logic circuitry package 1401 includes an interface 1423
to interconnect the package sub-components including the first and
second logic circuit 1403, 1405 to the print apparatus interface
bus, for example including three or four I2C compatible
interconnect pads. The logic circuitry package 1401 may include
separate, dedicated authentication logic 1417. The dedicated
authentication logic may include its own dedicated processor
separate from the CPU 1409, for example especially designed to
perform a specific calculation cycle a high number of times within
a short time window 1421. The time window 1421 may be stored in the
memory 1407. The logic circuitry package 1401 may include a first
timer 1429 to measure a timer period as indicated in a command, for
example to execute a specific task such as enabling a second logic
circuit. The first logic circuit 1403 may include, or be connected
to, a signal path and/or switch to enable the second logic circuit
1405 and/or to determine a time from which the logic circuitry
package 1401 is to respond to commands directed to the second,
reconfigurable, address (indicated by a block 1404).
[0197] The memory 1407 may store characteristics related to the
second logic circuit 1405. The memory 1407 may store a cell count
1431 for each of at least one class of cells 1451, 1453, 1457,
1455, to be associated with a number of cells of the respective
class(es). The memory 1407 may store a clock count 1433 which may
be associated with a relative or absolute clock speed of a second
timer 1435. The memory 1407 may store a revision ID 1419 to be
associated with a revision ID 1437 of the second logic circuit
1405.
[0198] Some of the previously mentioned data may be included as
digitally signed data, such as, for example, at least one of the
time window 1421, the revision ID 1419, the colour conversion
recipe 1413, the colour maps 1411, the cell count 1433. In one
example the cryptographic key 1441 is stored in separate, secure
hardware memory which should be understood as being encompassed by
the first memory 1407.
[0199] Furthermore, the memory 1407 may store at least one of
instructions 1443 to cryptographically authenticate messages using
the key 1441; instructions 1443 to provide an authenticated
challenge response within the time window 1421; and instructions
1445 to enable/activate the second logic circuit 1405 based on a
respective command including a timer period and/or a task,
including measuring the time period for example with the first
timer 1429; and other authentication or non-authentication
instructions. The logic circuitry package 1401 may be configured
such that communications in response to the commands directed to
the first address can be cryptographically authenticated using the
cryptographic key 1441, for example being accompanied by a message
authentication code and/or session key identifier, while responses
to commands directed to the second address may not be
cryptographically authenticated using the key 1441, for example not
being accompanied by a message authentication code and/or session
key identifier.
[0200] The second logic circuit 1405 includes a number of cells
1451, 1453 or cell arrays 1455, 1457 of different classes, the
numbers of which may correspond to the cell counts 1431, 1463. The
illustrated example includes four different cell classes but there
may be more or less classes of different cells. For example, of
each class, the cells may have a similar resistance, size, material
or other property. An array of cells may include at least 50 or at
least 100 cells. The cells may be adapted to heat or to sense a
certain property such as presence of print material adjacent the
cell. The cells may include resistors with or without sensing or
heating properties, or dummy cells to receive signals only without
influencing a read or write action. Depending on the type of cells,
at least one ADC and/or DAC 1467 may be used to convert signals
between digital and analogue, for example to facilitate signal
conversions via the interface 1423.
[0201] The second logic circuit 1405 may include a second timer
1435 which may determine an internal clock speed, which clock speed
may correspond to the stored clock count 1433.
[0202] The second logic circuit 1405 may store a revision ID 1437,
which may be associated with certain properties by the print
apparatus. The print apparatus may compare the first and second
revision ID stored on the respective first and second logic circuit
1403, 1405, as explained in relation to the first and second
validation responses.
[0203] The second logic circuit 1405 may be configured to
communicate, the at least one cell count 1463 pertaining to each
respective class of cells, which may correspond to the cell count
1431 of the first logic circuit 1403. In another example the cells
per class may be probed by the print apparatus logic circuit or the
logic circuitry package when installed in the print apparatus. For
example, a cell count of the second logic circuit 1405 may be
determined by measuring a last sensor or last sensor property. The
read or tested cell count may be compared to the cell count stored
in the first logic circuit 1403.
[0204] The logic circuitry package 1401 may include a field or data
portion 1465 storing a read/write history associated with read and
write actions associated with the second address 1404, for example
the temporary second address 1404. The logic circuitry package may
be configured to update that field after each respective read/write
session, using an algorithmic function that may be partly based on
the contents of the read/write session and/or on other variables,
which function may some form of bit scrambling.
[0205] The second logic circuit 1405 may include a second memory
arrangement 1461 that stores at least one of these second logic
circuit characteristics, such as the cell count 1463, R/W history
1465 and/or revision ID 1437.
[0206] As mentioned earlier in relation to a first and second
validation, in one example, communications from the second logic
circuit 1405 are not cryptographically authenticated using the same
cryptographic key as communications from the first logic circuit
1403 and/or are not cryptographically authenticated at all. In one
example the signal output of the second logic circuit 1405 may be
hardwired to scramble its output signals which in turn may be
decoded by the print apparatus logic circuit.
[0207] In certain examples, integrating relatively unexplored,
sometimes relatively complex, sensor devices to print apparatus
components could lead to unanticipated problems in the field. For
example, the manufacturer may not be able to predict exactly how
the innovation may work out after several years on the shelves in
different climate conditions and then in a connected state during
and between different printing conditions. In addition,
unanticipated cost and manufacturing issues could arise. Also there
may be a desire to provide an alternative component to connect to
the same print apparatus for other reasons. To alleviate any of
these potential challenges or other challenges, certain print
apparatus components such as print service cartridges may not be
equipped with sensor arrays. Accordingly, this disclosure also
encompasses other example logic circuitry packages that are
compatible with a host print apparatus logic circuit that was
originally adapted to communicate to the second logic circuits with
sensors, which host print apparatus may in certain instances
already be operational at many different customer locations around
the globe prior to designing these other compatible packages. These
other compatible packages are adapted to not rely on the same
second logic circuits with sensors to communicate with the original
host print apparatus logic circuit. In these examples, certain
physical hardware components such as sensor devices may, at least
partly, be replaced by different virtual or hardwired components or
data representative of the different properties or states depending
on the received printer command, which may allow the print
apparatus to accept these logic circuitry packages as including
original sensor arrays. In addition to being operable, these
compatible packages may need to pass certain integrity checks such
as the mentioned first and second validations.
[0208] In one example, these compatible packages can be relatively
cheap or relatively easy to manufacture. In other examples, these
compatible packages can be more reliable then the sensor-arrays
logic circuitry package of this disclosure. In again other
examples, these compatible packages provide for an alternative to
sensor array-based second logic circuits. In again other examples,
these compatible packages may facilitate testing or servicing the
print apparatus or other components of the print apparatus. The
compatible package may be designed to output similar responses to
print apparatus logic circuit commands so that the print apparatus
logic circuit accepts the responses, as if an original second logic
circuit is installed. In certain examples, the compatible
integrated circuits could be provided when the certain sensor-array
based logic circuitry packages in the field fail to replace these
failing integrated circuits; to save costs; because they are easier
to manufacture; as an alternative; or for other reasons. FIG. 15
discloses an example of such other, compatible logic circuit
package. Earlier mentioned examples also encompass such alternative
package, such as for example FIG. 4B.
[0209] FIG. 15 illustrates a compatible logic circuitry package
1501 configured to have similar responses to respective print
apparatus commands as the logic circuitry package 1401 of FIG. 14.
The logic circuitry package 1501 includes an interface 1523 to
connect to the print apparatus interface bus, for example including
three or four I2C compatible interconnect pads. The first logic
circuitry package 1501 includes a memory 1507 and a CPU (central
processing unit) 1509. The package 1501 may store instructions 1545
to respond to corresponding commands directed to (i) a first
address; and, at an enable command including a time period, (ii) an
initial second address; and when receiving a reconfigured address,
(iii) a reconfigured second address (as indicated by block 1502,
1504). The memory 1507 may store at least one of characteristics
1515, 1519, 1537, including identity data and a status 1527
associated with the replaceable print component.
[0210] This example package 1501 may include certain LUTs,
algorithms 1505 and/or hardwiring 1551, 1553, 1555, 1557 configured
to generate responses that the print apparatus logic circuit
associated with these cells. In one example, the hardwiring of the
logic circuitry package 1501 has similar properties as the cell
arrays and cells of FIG. 14, to assist in generating compatible
output signals or receiving input signals. In one example the
hardwiring is to receive input signals and/or to mimic cells such
as resistors and registers. In one example, the hardwiring may
include a second timer or clock corresponding to a clock count
1533. In another example the second logic circuit of FIG. 14 may be
replaced by a full virtual emulation, for example using said LUT
and/or algorithm 1505, without additional hardwiring. The output
LUT 1505 may be configured to associate certain received commands
and signals with certain acceptable outputs, for example at least
partly based on an updated status 1527. In addition to, or instead
of, the output LUT 1505, algorithms may be provided to generate
compatible outputs. Hence, the output LUTs, algorithms 1505, and
the hardwiring 1551, 1553, 1555, 1557 may be configured to
represent a sensor array 1451, 1453, 1455, 1457 or a complete
second logic circuit 1405 (FIG. 14), which in this example of FIG.
15, is at least partly virtual and does not need to represent an
actual status of the print component in the way the print apparatus
would interpret this. Rather the LUT, algorithm 1505 and/or
hardwiring 1551, 1553, 1555, 1557 may facilitate a working,
compatible logic circuitry package 1501 to be able to print with
the print apparatus.
[0211] The compatible package 1501 stores the revision ID 1519,
1537, for example in one field or in two fields, or is at least
configured to provide it to the print apparatus based upon a
corresponding read request. The revision ID 1519, 1537 is another
ID that the print apparatus logic circuit may associate with the
second logic circuit, which as explained in this example may not be
present physically but may to some extent be represented virtually.
Similarly, the package 1501 may store a cell count 1531, 1563, a
clock count 1533 which may or may not be associated with a relative
or absolute clock speed of the timer 1529, 1535. The logic
circuitry package 1501 may be configured to store and/or output
read/write history 1565 associated with commands to the
reconfigured second address 1504. The revision ID, cell count,
clock count and read/write history may be readably provided in
response to read requests via the second address, for example the
reconfigured second address, and in a further example may not be
cryptographically authenticated using the cryptographic key
1541.
[0212] Certain features of this logic circuitry package 1501 may be
similar to, or the same as, the first logic circuit 1403 of FIG.
14. For example, the characteristics may include colour, print
material type, colour maps 1511, colour conversion recipes 1513,
and other characteristics. The identity or identities 1515 could
include a product number, brand and/or any code to be associated
with the identity of the replaceable print apparatus component. The
status 1527 may include data that the print apparatus associates
with a print material level. The logic circuitry package 1501 may
include a cryptographic key 1541 to cryptographically authenticate
messages, which messages may include any of said status,
characteristics and/or identity. The logic circuitry package 1501
may include separate, dedicated authentication logic 1517 and store
a corresponding time window 1521. The logic circuitry package 1501
may include a first timer 1529, 1535 to measure a timer period as
indicated in a respective command. In one example a single timer
device 1529, 1535 could be used to represent the first and second
timer.
[0213] Furthermore, the package 1501 may store at least one of
instructions 1543 to cryptographically authenticate messages using
the key 1541; instructions 1543 to provide an authenticated
challenge response within the time window 1421; and instructions
1545 to set the address 1502, 1504 based on a respective command
including a timer period and/or a task, including measuring the
time period for example with the timer 1529, 1535; and other
authentication or non-authentication instructions. The logic
circuitry package 1401 may be configured such that communications
in response to the commands directed to the first address are
cryptographically authenticated using the cryptographic key 1541,
for example being accompanied by a message authentication code
and/or session key identifier, while responses to commands directed
to the second address may not be cryptographically authenticated
using the key 1541, for example not being accompanied by a message
authentication code and/or session key identifier.
[0214] Some of the previously mentioned data portions may be stored
as digitally signed data, such as, for example, at least one of the
time window 1521, the revision ID 1519, 1537, the colour conversion
recipe 1513, the colour maps 1511, the cell count 1533 and other
data, to allow a printer to correspondingly decode/unsign the
data.
[0215] In the examples of FIGS. 14 and 15 interface connection pads
of the interface 1423, 1523 of the logic circuitry package 1401,
1501 may correspond to the interface contacts illustrated in FIGS.
13A and 13B. The example of FIG. 15 may be provided entirely or
largely on the outside of the print apparatus component of FIG. 13B
while the example of FIG. 14 may be provided partly or largely
inside of the print apparatus component of FIG. 13B (e.g. against
an inner wall of the print material reservoir), except for the
interface connection pads.
[0216] Each of the logic circuitry packages 400a-d, 806a-d, 900,
1401, 1501 described herein may have any feature of any other logic
circuitry packages 400a-d, 806a-d, 900, 1401, 1501 described herein
or of the processing circuitry 424. The processing circuitry 424
described herein may have any feature of the logic circuitry
packages 400a-d, 806a-d, 900, 1401, 1501. Any logic circuitry
packages 400a-d, 806a-d, 900, 1401, 1501 or the processing
circuitry 424 may be configured to carry out at least one method
block of the methods described herein. Any first logic circuit may
have any attribute of any second logic circuit, and vice versa.
[0217] FIG. 16 is an example of a method, which may comprise a
method of calibrating a response to a request for sensor data by a
print apparatus. The method may be carried out by logic circuitry
associated with a replaceable print apparatus component installed
in a print apparatus. In some examples, such calibration may be
used to prevent `clipping` of sensor data. For example, as
described above, in the case of a fluid level sensor, a reading may
be lower when the sensor is submerged in liquid than when the
sensor is exposed (see also FIG. 20C). Therefore, an initial
calibration, which may be carried out when a printer cartridge is
full, may provide a reading at the lower end of an expected range.
In order to prevent a higher reading from being `clipped`, this
lower reading may be calibrated so as to be within an anticipated
range. As is further set out below, in some examples, this may
comprise adjusting an offset and/or a gain parameter. For example,
there may be an offset and/or gain associated with an analogue to
digital conversion of the data and the offset and/or gain applied
may be configurable. In a further example, calibration may be
applied by adjusting the heat parameters such as power applied to
heater cells (e.g., heater cells 416), heat time of heater cells,
and/or selection of heater cells, in a heater array, wherein the
heat parameters may also be considered calibration parameters.
[0218] Such parameters may be stored in a memory of a logic
circuitry package. For example the offset and/or gain parameter may
be stored in a memory register, and may be overwritten by a
modified parameter. This could be used, for example in an analog
bias stored in the analog to digital converter 444 shown in FIG. 4.
Amplifiers in the analog bias block may receive the digital offset
and/or gain setting stored in the digital register block, which
sets how the amplifiers will behave. The modified offset and/or
gain parameter may be selected based on information received from a
host apparatus. In some examples, the offset and/or gain parameter
may be configurable within a range.
[0219] For example, a gain parameter may be modified within a range
of 1 to 64. A gain parameter of n has the effect of multiplying a
measured value by n.
[0220] The offset parameter may be modified to comprise a value
between 0 and 255, or a subrange thereof, for example between 50
and 100.
[0221] It may be noted that each step in the offset parameter will
change the A/D output count by an amount that is a function of the
gain parameter. Therefore, at high gain parameter settings, a small
change in offset parameter value may move the output count value
considerable (for example by hundreds of counts up or down) whereas
at lower gain values, a larger range of offset parameter values
must be used to have the same effect.
[0222] The method comprises, in block 1602, responding to a data
request, in this example a sensor data request, received from the
print apparatus by returning a first response. In some examples,
the first response may comprise a sensor reading. In another
example, the response may comprise data held in a memory of the
replaceable print apparatus component. In some examples, the data
request may be a request for data held in a memory of the
replaceable print apparatus component (i.e. a memory read request).
In some examples, the sensor data request may comprise at least two
commands or request elements: a first command triggering data
acquisition and a second command triggering transfer of the sensor
data to the print apparatus
[0223] For example, the sensor data request (or the first command
thereof) may comprise a write request, which includes a sensor cell
identifier. In some examples, a sensor type may be identified. For
example, the sensor data request may specify that one of the level
sensor, global temperature sensor resistor (TSR), strain gauge,
crack detector or thermal diode sensor should be queried. In some
examples, a specific sensor cell or set of sensor cells may be
specified in such a write request. For example, the sensor data
request may identify a specific sensor using an identifier such as
an index/address or the like. In some examples, such identifying
data may be written to one or more memory register(s), which may be
a predetermined or dedicated register(s). The data may be read in
response to a read request, which may in some examples identify the
memory portion or memory register using the memory address.
[0224] Block 1604 comprises receiving a calibration parameter from
the print apparatus. For example, calibration parameters may be
used for each sensor conversion and/or read response. For example,
processing circuitry of the print apparatus (e.g. controller 304 or
logic circuitry 808) may determine that the result is outside of a
predetermined range, and may send a new calibration parameter to be
used in a subsequent sensor read operation in order to reach a
point where a response is within the predetermined range. In some
examples, the print apparatus processing circuitry may determine
that the criteria (for example, whether the response is within a
predetermined value range) is not met and may send a new
calibration parameter intended to result in a value within that
range. In some examples, the print apparatus processing circuitry
may determine how the criteria is not met--for example, the print
apparatus processing circuitry may determine that a value of the
first response is clipped, too high, or too low, and/or an
indication of the magnitude of the departure from the predetermined
criteria.
[0225] For example, a determination that a reading is too high may
be met with a first particular predetermined calibration parameter
being sent (or a first particular adjustment being made to a
previous calibration parameter), and an indication that a reading
is too low may be met with a second particular predetermined
calibration parameter being sent (or a second particular adjustment
being made to a previous calibration parameter). The method of
converging on an appropriate calibration parameter may be a linear
adjustment, a binary adjustment (e.g. adjusting one bit of a value
used in determining the output value), or some other modification
to converge on a calibration parameter which results in a response
accepted as meeting predetermined criteria. A binary adjustment may
comprise altering one bit at a time, starting with the most
significant. This may also be referred to as a binary search. For
example, bits of the parameters may be changed in order from the
most significant to the least significant, where a logic 1 may be
changed to a logic 0 if a reading is indicated to be too low (but
left unchanged if the received response is too high), and a logic 0
may be changed to a logic 1 if a received response is indicated to
be too high (but left unchanged if the reading is too low). In
other examples, if the received response is indicated to be too
high, a new calibration parameter (for example, a new offset
parameter) may be the previous calibration parameter, less half its
value (wherein the previous calibration parameter is the
calibration parameter which the print apparatus processing
circuitry determines or assumes was used in determining the first
response). If however the received response is indicated to be too
low, a modified parameter may be the previous calibration parameter
increased by half its value. In other examples, the parameter may
be adjusted in other ways.
[0226] Block 1606 comprises returning a second response which is
different from the first response. In some examples, the manner in
which the first response and the second response are different may
be deterministic, based on the new calibration parameter provided
in block 1604. In some examples, the second response may be
returned following receipt of a second sensor data request.
[0227] Performing a calibration step may allow for smaller sensors
and/or greater variation in fabrication and operating conditions,
as the variability this introduces can be countered by subsequent
calibration. In some examples, such calibration may be performed
after a replaceable print apparatus component is installed, which
may reduce a requirement for non-volatile memory within processing
circuitry associated therewith. Calibration could be carried out
every time a print apparatus is switched on, when a new print
apparatus component is installed, periodically in use of a print
apparatus or at some other time.
[0228] The first response sent in block 1602 need not be the first
response in a calibration sequence. Where data may be `clipped`, it
may be the case that at least some successive responses return the
same value (e.g. 0 or 255 in an 8 bit range), despite using
different calibration parameters. However, in that case, a
calibration sequence will likely continue until a value which is
neither 0 nor 255 and thus a sequence of two responses will be
different to one another.
[0229] FIG. 17 describes an example of sensor calibration in
greater detail.
[0230] In this example, in response to receiving a sensor data
request via an I2C bus in block 1702, the method comprises,
requesting (e.g. causing generation of and/or retrieving) sensor
data in block 1704. For example, this may comprise reading a
resistance of a liquid level sensor, determining a reading from a
strain gauge, or the like. Therefore, in some examples, requesting
sensor data may comprise applying a current to at least one
resistor and generating a sensor voltage. In this example, the
reading is converted to a digital reading using a configurable
offset and/or gain parameter. Thus, block 1706 comprises converting
the sensor data measurement into a digital parameter using an
analogue to digital converter having an initial gain parameter and
a voltage offset adjustment parameter (Vdac). In one example,
calibration parameters may be provided in block 1702 for a first
conversion, or default calibration parameters may be used for the
conversion step of block 1706. In some examples the resulting
digital reading may be stored in a memory, for example in a
predetermined memory location, which may be predetermined memory
register.
[0231] The sensor data request received in block 1702 may comprise
a write request, which includes a sensor cell identifier. In some
examples, a sensor type may be identified. For example, the sensor
data request may specify that one of the level sensor, global TSR,
strain gauge, crack detector or a thermal diode sensor should be
queried. In some examples, a specific sensor cell or set of sensor
cells may be selected. For example, the sensor data request may
identify a specific sensor/sensor cell using an identifier such as
an index, address or the like. In some examples, such identifying
data may be written to one or more memory register(s), which may be
a predetermined or dedicated register(s).
[0232] Receipt of such a sensor data request may trigger a sequence
of actions, for example including blocks 1704, block 1706, and/or
storing the digital parameter in a memory.
[0233] In some examples, the method may further comprise receiving
a read request from processing circuitry, the read request being a
request for the digital parameter, for example a request to read
the predetermined memory location. In other examples, the digital
parameter may be transmitted without requiring a read request to be
received.
[0234] Block 1708 comprises receiving a first calibration
parameter, which in this example is an offset parameter. This may
be indicative that a print apparatus processing circuitry has
determined that the first response is greater than a maximum value
or less than a minimum value of a predetermined range (as stated
above, certain calibration parameters may have been applied for an
earlier, e.g., first, conversion in block 1706, but these may have
returned these unsuitable values, and, hence, need further
calibration as determined by the print apparatus processing
circuitry). As noted above, the offset parameter may be a linear
modification to a previously used offset parameter, a binary
modification to a previously used offset parameter, or some other
modification which may be intended (in some examples over a
plurality of iterations) to converge on a count in an appropriate
range.
[0235] Block 1710 comprises adjusting a stored offset parameter to
the new offset parameter. In some examples, adjusting the offset
parameter may comprise overwriting an offset parameter stored in a
memory register with a modified offset parameter. More generally,
any calibration parameter may be overwritten in a similar
manner.
[0236] Block 1712 comprises requesting sensor data as described in
relation to block 1704. Block 1714 comprises converting the sensor
data measurement into a digital parameter using an analogue to
digital converter having the first offset parameter.
[0237] As outlined above, once determined, the digital parameter
may for example be stored in a memory (and in some examples may be
stored in the same memory location as the digital parameter
generated in block 1706) and/or supplied to the processing
circuitry of the print apparatus automatically, or following
receipt of a read request, or in some other way.
[0238] From here, the method may proceed in one of two ways. Block
1716 comprises receiving a second calibration parameter, which may
be an indication that the processing circuitry of the print
apparatus has determined that second response is greater than a
maximum value or less than a minimum value of the predetermined
range. In this case, the method loops, with further modified offset
parameters being applied until the sensed data is within the
predetermined range. In some such examples, the print apparatus
processing circuitry may be configured such that, if consecutive
readings fall outside the predetermined range at different ends of
that range, then half the previous offset parameter may be added or
subtracted from the previous offset parameter until a reading which
is within the range is seen. However, in some examples, if
consecutive readings fall outside the predetermined range at the
same end of the range, the print apparatus processing circuitry may
be configured such that the offset parameter which is sent may
continue to be halved/doubled as appropriate. Other methods of
converging on appropriated calibration parameters may be used, for
example as discussed above.
[0239] Block 1718 comprises terminating the method. In some
examples, the method may be terminated on receipt of an indication
that the response is acceptable. In other examples, the absence of
an indication that the responses fall outside of a predetermined
range, or an absence of further calibration parameters, may serve
to terminate the method.
[0240] To consider a particular example in which an array of
thermal (ink level) sensor cells and an array of strain gauge
sensor cells is provided, such sensors may each generate a unique
voltage based on the silicon process variation and ink supply
operating temperature. These sensor voltages may be read using an
analog-to-digital (ND) converter which is integral to the logic
circuitry. Such an ND circuit may have a finite input voltage
range. To ensure all sensors produce a voltage that will be in
range for the measurement sequence, a voltage calibration process
may be performed before measurements begin.
[0241] For both ink level sensor cells and strain gauge sensor
cells, the measurement sequence can result in a large change in the
output value of the ND (counts). Therefore, a specific starting
count value range, unique for each sensor type, may be targeted
before ink level or deflection measurements begin.
[0242] Some examples of ink level sensors work by measuring the
thermal response change to a local heating event. If fluid is
present over the sensor cell location, the thermal response change
(e.g. counts of an analogue to digital converter receiving an input
comprising a resistance) will be less than if there is air present
over the sensor. Heating a sensor cell tends to increase its count
reading.
[0243] In some examples, calibration may be carried out while the
sensor cell(s) are not heated, and to ensure that readings are not
clipped when sensors exposed to air are heated, the target count
may be at the low end of a count range. For example, if a maximum
count value is 255 counts, the target calibration value when the
sensor cell is not heated may be approximately 10-30 counts or
10-50 counts. In another example, a calibration may be carried out
using a first sensor cell while heating. This may be carried out
using the sensor closest to the logic circuitry as this may be
expected to provide the highest reading as it is less affected by
losses in transmission. This heated sensor may be calibrated to
provide a reading in the region of 170-240 counts (e.g. in dry
state) or 100-180 counts (e.g. in wet state), with the knowledge
that other sensor cells will return a lower reading.
[0244] Some examples of strain gauge sensor cells measure the
mechanical deflection of the ink container lid during fluid priming
(which is also known as hyperinflation). In one design, these
sensor cells may lower their count value during lid deflection,
meaning the target calibration range when not deflected is high,
for example being at over 200 counts when the count range is from 0
to 255, for example being approximately 200-245 or 225-245 counts.
This may allow a count reduction to around a minimum count of
around 100 when a hyperinflation event occurs.
[0245] In summary therefore, if a calibration result is outside a
target range, offset, gain and/or any other parameter of the A/D
converter may be modified until it is within range. In other
examples, test parameters (i.e. sensor reading parameters) may be
alternatively or additionally be varied to return a result within a
target range. For example, heat outputs or electrical parameters
may be adjusted.
[0246] It may be noted that the target ranges for calibration for
the sensor types are different. Therefore, in one example, the
method may comprise calibrating a first sensor type to provide a
calibration value in a first range, and calibrating a second sensor
type to provide a calibration value in a second range, where the
first and second range may be non-overlapping, or only partially
overlapping. In some examples, the first and second ranges may be
at the higher and lower end of a larger range.
[0247] In some examples, the individual sensor cells and the range
of responses from a set of sensor cells may be calibrated, for
example to determine that the spread between the maximum and the
minimum readings is within a predetermined threshold. For example,
temperature sensor cells may be expected to provide a set of
calibration readings which fall within a spread of a first number
of counts (for example, within 20 counts of each other), while
strain gauge sensor cells may be expected to provide a set of
calibration readings which fall within a spread of a second number
of counts (for example, within 100, or 80 counts of each other).
This range may be greater due to built-in stress during
manufacturing. The first and second number may be the same or
different. Limiting the spread in this way means that calibration
may be carried out relative to a subset of sensor cells--or even
relative to a single sensor cell, which in turn may shorten the
time taken to fully calibrate the readings for the set of sensor
cells. In this way, if the calibrated readings for the sensor
cell(s) are within an expected range, the values returned from the
other elements can be expected to be within that range. In some
examples, the spread in values may be determined in a factory
setting prior to distribution of the apparatus. In some examples,
at least a predetermined number of out-of-range responses may be
expected before an `in range` response is seen.
[0248] In some examples, the method of FIG. 17 may be carried out
during a time period during which a logic circuitry package is
accessible via a second address, as described above.
[0249] FIG. 18 is another example of a calibration operation, which
may be a calibration operation of at least one sensor for sensing a
characteristic of a replaceable print apparatus component. The
method may be carried out by logic circuitry associated with a
replaceable print apparatus component installed in a print
apparatus, and which describes a method of setting parameters for a
whole array based on a calibration result for a single sensor.
[0250] Block 1802 comprises configuring an offset value in a Vdac
register. For example, this may comprise storing a value in a Vdac
register. An initial value may, in some examples, be received from
a host apparatus (e.g. a printer) in which sensor apparatus is
installed. In other examples, the initial value may be a default
value, for example a default value of 0, or a mid-range default
value (for example, a default value of 72 in a range of 0 to 255),
or a default value at the top of a range (e.g. 127, or 255,
depending on the available range). In again other examples, the
initial Vdac value may be stored on a memory of the logic circuitry
package, for example of a first logic circuit, to be retrieved by
the host apparatus via the first logic address outside of the time
period, and subsequently to be input by the host apparatus to the
second logic circuit. The offset value may compensate for an offset
error in Vdac, and/or may be set to reduce a risk of `clipping` as
discussed above.
[0251] Block 1804 comprises selecting a cell to test or read. In
some examples, the cell may be selected by writing a cell address
into a memory register. The selected cell may depend on the
configuration of the sensor array, and/or on test parameters. For
example, if the calibration is to be carried out in relation to a
liquid level sensor as shown in FIG. 13, it may be intended to test
the sensor such that the reading may be expected to be at the
higher end of an anticipated range. Therefore, a sensor which is
close to the top of the array may be selected, to minimise signal
transmission losses. In addition, an instruction to heat the sensor
may be generated. In another example, it may be intended to test
the sensor such that the reading may be expected to be at the lower
end of an anticipated range. In such an example, a sensor cell
which is relatively near the bottom of the array may be selected,
and the sensor may not be heated, so as to provide an expected low
voltage return at the analogue to digital converter.
[0252] Block 1806 comprises receiving, by processing circuitry
which comprises the sensors, a sensor read result, and sending the
read result to a host apparatus. In this example, the read result
comprises a count value output by an analogue to digital converter,
which may for example be stored in a memory (for example, a memory
register) of processing circuitry which comprises the sensors. Such
a read result may be sent to the host apparatus, for example
following receipt of a read request therefrom. The host apparatus
may determine if the count value in within a predetermined range,
such that a count value within the range is considered suitable,
and a count value outside the range is not.
[0253] If the count value is suitable, then the currently set
offset value in the Vdac register may be adopted for that sensor
array and the method may terminate. However, in some examples the
method continues with block 1808, which comprises receiving a
modified offset value, for example from the host apparatus. This
provides an indication that the count value is not suitable. In
block 1810 the offset value to be used in sensor reading conversion
is adjusted to the received offset value, and the process repeated,
for example with the print apparatus triggering a new read of the
same sensor cell as described in relation to block 1804
[0254] The method of FIG. 18 may then be repeated for another
sensor cell, sensor and/or sensor array. The range of suitable
count values may be different for different sensors and/or sensor
arrays. A similar method may be used to set one or more signal gain
parameters and/or other operational parameters such a heat
and/electrical sensor read parameters.
[0255] In some examples, the methods of any of FIGS. 16 to 18 may
be carried out by logic circuitry associated with a replaceable
print apparatus component installed in a print apparatus. In some
examples the methods of FIGS. 16 to 18 may be carried out during a
time period during which a logic circuitry package is accessible
via a second address, as described above. In some examples, the
methods of FIGS. 16 to 18 may be carried out following
authorisation, as described above.
[0256] FIG. 19A shows an example methods of reading data from logic
circuitry. In one example, the method may be carried out by logic
circuitry associated with a replaceable print apparatus component
installed in a print apparatus. In some examples the method of FIG.
19A may be carried out during a time period during which a logic
circuitry package is accessible via a second address, as described
above. In some examples, the method of FIG. 19A may be carried out
following authorisation and/or calibration, as described above.
Such calibration may comprise calibration of response parameters,
such as Vdac offset and/or gain. In some examples, the calibration
may be carried out as described in relation to any of FIGS. 16 to
18.
[0257] For example it may be that it is intended to monitor various
parameters of a replaceable print apparatus component. For example,
as mentioned above, in the case of a container for consumable
materials, a level of the consumable materials may be measured
using a suitable level sensor. Some examples of fluid level sensors
are described herein, but other sensors may be used in other
examples. In an alternative configuration, instead of measuring a
material level directly, the amount of material consumed may be for
example, estimated or measured, to infer a level remaining. For
example, an ink level may be inferred from a drop or page count as
stored in a respective memory field, for example in the first logic
circuit. For example, an accelerometer may be used to detect motion
of a print head and thereby provide an approximation of ink
delivered to a page, or a typical ink usage could be predetermined
for a print job or a printed page, and the number of jobs/pages
printed may be monitored to determine an estimate (which in some
examples may be refined by considering the time taken to carry out
a print job). In other examples, fluid level may be measured
directly in some other way, for example using resistive, capacitive
or inductive sensors, optical sensor, Hall effect sensors with
floating elements, or the like. In still further examples, fluid
flow from a container may be measured using a flow sensor, for
example inductive sensing for ionic fluids.
[0258] In some examples, a print material container such as a print
agent cartridge may be pressurised (or more generally may be
subjected to a pneumatic stimulus). This may assist in ejecting
print agent therefrom. For example, this pressurisation event may
comprise introducing air into a chamber containing a fluid. In some
examples, the fluid and any introduced air may be kept separate
from one another, for example by introducing the air into a
collapsible chamber, such as a bag, which is itself arranged in the
chamber containing the fluid. The function of such a chamber may be
tested, for example in a `hyperinflation` event, in which the
pressure may be increased to a greater degree than may be expected
during normal operation of the print apparatus to perform printing
actions. This may for example provide a `priming` function, in
which material which may be occluding ejection nozzles or the like
may be dislodged. While in some examples, the pressure may be
measured directly, in other examples, an effect of the
pressurization may be measured. For example, an air movement or
pneumatic stimulus may be monitored, or a deflection in a surface
caused by a change in pressure may be detected.
[0259] While particular arrangements using strain resistors are
described in detail herein, other examples of sensors may be
provided. For example, in one example, a temperature sensor may be
provided to determine a printing fluid temperature. Thus, a sensor
assembly may comprise at least one level sensing element, at least
one strain sensing element, and at least one fluid temperature
sensing element (which may for example comprise a temperature
sensitive resistor.
[0260] In other examples, a temperature sensor may be provided to
determine ambient temperature and/or mechanical integrity, which
may for example be monitored using a crack detector.
[0261] In one example, a sensor assembly may contain an array of
heater elements and sensors. There may be a plurality of sensor
types, for example five different sensor types, each with a
different sensing function. In one example, there may be around 255
sensors, with 126 of these being thermal sensors to measure
printing fluid level (thermal point sensors), each of which may be
associated with a heater element. In addition, there may be at
least one global average, or ambient, temperature sensor which may
be a Temperature Sensitive Resistor (TSR), and at least one
absolute fluid temperature sensor, to determine the temperature of
the fluid associated with the level sensor (which may be a diode or
the like), at least one sensor to measure mechanical deflection
(e.g. one or a number of strain gauges), and at least one sensor to
determine mechanical integrity (e.g. a crack detector). The average
temperature sensor may comprise a distributed sensor cell, for
example, a resistive wire which may for example run along the
length of a substrate. The resistive value represents an `average`
temperature over the length. This may be contrasted with a point
sensor, which will take a localized reading.
[0262] In some examples, the sensors of the sensor assembly may be
controlled by a common logic circuit, for example, a logic
circuitry package, first logic circuit or second logic circuit or
processing circuitry 424 as described above.
[0263] In some examples, the sensors of the assembly may be read
using a specific I2C communication sequence, or some other
communication sequence.
[0264] Providing converged circuit architecture which enables
multiple sensor types to be included with little additional silicon
cost is advantageous in simplifying manufacture and reducing costs
associated therewith. In some examples, the same routine may be
used to query a plurality of sensor types, as is set out below.
This may reduce and/or simplify measurement time and/or firmware
complexity.
[0265] In some examples, the number of data readings requested by
logic circuitry of a print apparatus and returned by a logic
circuitry package may depend on whether the request is for data
indicative of a print material level or for data indicative of a
pressurization event. In the event that the request is a request
for data indicative of the print material level, there may be
request(s) for a first data response having a first number of data
readings, and in the event that the request is a request for data
indicative of a pressurisation event, there may be request(s) for a
second data response having a second number of data readings. The
first number of data readings may be different from the second
number of data readings. In some examples, the first number of data
readings may be greater than the second number of data readings. In
addition, the first number of data readings may have a different
range than the second number of data readings. Moreover, in one
example, the first data response may have characteristics such as a
decreasing trend based on a predetermined order of the sensors. The
request(s) for the first data response may comprise a plurality of
different data requests. For example, logic circuitry of the print
apparatus (such as the controller 304 or the logic circuitry 808)
may make a first number of separate data requests. The request(s)
for the second data response may comprise a plurality of different
data requests (for example, the logic circuitry of the print
apparatus may make the second number of data requests). The
requests may comprise memory read and/or write requests.
[0266] The method of FIG. 19A comprises in block 1910, receiving a
sensor data request. In block 1912, it is determined whether the
request is for data indicative of a print material level or for
data indicative of a pressurization event. In the event that the
request is a request for data indicative of the print material
level, the method proceeds to block 1914, and the logic circuitry
responds with a first data response having a value within a first
range. In the event that the request is a request for data
indicative of a pressurisation event, the method proceeds to block
1916, and the logic circuitry responds with a second data response
having a value within a second range. In some examples, the first
and second ranges may be distinct, i.e. non-overlapping. The first
and second ranges may be sub-ranges at respective low and high ends
of a broader maximum range.
[0267] In some examples, the request in block 1910 is in the form
of a write command or request, which may identify whether the
request is for data indicative of a print material level or for
data indicative of a pressurization event. In some examples, blocks
1914 may be carried out following a read command/request received
from logic circuitry of print apparatus, requesting sensor
data.
[0268] In some examples, prior to providing the first or second
data response, parameters for performing a measurement may be set,
for example through a calibration routine as described above. For
example, the power or duration of a heat event and/or the duration
of the measurement event, or electrical testing parameters may be
determined.
[0269] In some examples, providing the first or second data
response comprises iteratively providing data relating to different
sensors and/or different sensor cells. In some examples, there may
be a plurality of sensor cells which form part of a single sensor,
such as a print agent level sensor, and each of these cells may be
read in turn. In some examples, sensed data is written into a
memory register and supplied therefrom to a host apparatus, for
example in response to a read request. In some examples, the data
provided by each sensor cell is read into a particular memory
location, for example a memory register, and then overwritten by
the data from the next sensor cell once it has been read therefrom
for transmission to the host apparatus, for example following a
read request received from that host apparatus to read that memory
location. In some examples, obtaining the sensor data may be
carried out in a similar manner to that used to determine
individual calibration readings.
[0270] In other words, a first command, which may be a write
command, may provide information allowing a sensor type/sensor cell
to be identified, and may trigger (in some examples on receipt of a
specific "conversion" command, but in other examples in response to
the first command) a sequence of events to carry out sensing,
execute an ND conversion to store the conversion value into a
memory location, which may be predetermined (for example,
comprising a sensor data register). The sensing may be carried out
using parameters (e.g. electrical test parameters, heating
parameters, timing of measurements, etc.) which may also be stored
in a memory (in some examples, in separate memory registers),
and/or may be provided with the command. The ND conversion may be
carried out using parameters which may also be stored in a memory
(in some examples, in one or more memory register(s)).
[0271] FIG. 19B shows an example of a method of reading a plurality
of sensor cells of a sensor array. The method comprises receiving,
in block 1920, an indication of an address of a sensor cell. For
example, the address of the sensor cell may be written into a
particular memory register and/or the indication of an address of a
sensor cell may be provided as part of a write request, which may
provide an indication of whether the request is for data indicative
of a print material level or for data indicative of a
pressurization event, as described in relation to block 1910. Block
1922 comprises setting the test parameters for the cell. For
example, this may comprise setting a heat level and/or duration for
a heater, or setting a voltage and/or current level for an
electrical test of a resistor or the like. Block 1924 comprises
carrying out the test by querying the sensor cell and block 1926
comprises storing the result. The result may provide a data
response for that cell. In some examples, the result may be stored
in a second particular register.
[0272] In some examples, each data response may be requested and/or
read out onto a communications bus in turn. In some examples, a
request for a reading from each of a plurality of cells may be
managed by the host apparatus, which may request a sensor reading
from a cell, supplying data identifying that cell (for example, the
cell address and, in some examples, the sensor type), triggering
the method of FIG. 19B. In some examples, once the sensor cell
reading has been acquired and placed in a local memory by the
replaceable print apparatus component, the host apparatus may make
a read request (for example, requesting that the content of a
specific memory register is read onto the bus). Once data has been
acquired for that cell, the host apparatus may then initiate the
process for a different cell/sensor type.
[0273] In another example, the process may be controlled by the
logic circuitry/processing circuitry on which the sensors are
provided. For example, this may comprise receiving, from a host
apparatus, a request to provide readings from a particular sensor
array (for example, from a strain sensor array, or from a fluid
level sensing array), and the logic circuitry/processing circuitry
may then initiate a routine to query sensor cells of that
array.
[0274] In some examples, prior to receiving a sensor data request
in block 1910, the method may comprise receiving a first command
indicative of a first time period, and in some examples a task, and
enable access to processing circuitry by second address for
duration of the time period. In other words, the method of FIG. 19A
(and/or the method of FIG. 19B) may, in some examples, follow a
method as described in relation to FIG. 5. The sensor data request
received in block 1910 may be sent to the second address. In some
examples, the method of FIG. 19A (and/or the method of FIG. 19B)
may be carried out during a time period during which a logic
circuitry package is accessible via a second address, as described
above.
[0275] The sensor data request may comprise a write request, which
may include a sensor cell identifier, for example as described in
relation to Block 1920. In some examples, a sensor type may be
identified. For example, the sensor data request may specify that
one of the level sensor, global TSR, strain gauge, crack detector
should be queried. In some examples, a specific sensor cell or set
of sensor cells may be selected. For example, the sensor data
request may identify a specific sensor using an identifier such as
an index or the like.
[0276] In some examples, such identifying data may be written to
one or more memory register(s), which may be a predetermined or
dedicated register(s).
[0277] FIG. 20A shows an example of a fluid level sensor 2000 in
association with a circuitry package 2002. The fluid level sensor
2000 in this example comprises a relatively long thin silicon strip
2004 which supports 126 resistive sensor cells 2006 (only some of
which are shown to avoid over complicating the drawing). The fluid
level sensor 2000 further comprises a set of heating elements 2008
(AKA heater cells), one in association with each sensor cell 2006.
The heating elements 2008 may be capable of providing heat at a
plurality of power levels. In one example, there are three heating
elements with each resistive sensor cell 2006, in order to provide
three heating levels. In other examples, the heating elements may
be controllable to output a plurality (e.g. three) of heating
power. In order to read the sensor 2000, the circuitry package 2002
sends a signal to at least one heating element(s) 2008, which may
be heating element(s) associated with a sensor cell to be read.
This causes the heating element 2008 to emit a pulse of heat. One
of the sensor cells 2006 is then selected to be read. This process
is repeated until all 126 sensor cells 2006 have been read. In this
example, the sensor readings, which are essentially voltage
readings, as submitted to an analogue to digital converter 2010.
The conversion applied by the analogue to digital converter 2010
may be predetermined or may for example be set by a calibration
process as detailed above
[0278] In one example, the circuitry package 2002, the analogue to
digital converter 2010 and the fluid level sensor 2000 are all
arranged on a single, common substrate, which may be a silicon
substrate. Part of this substrate is exposed to the fluid being
sensed (the part with sensors, or most of the part with sensors).
The substrate may in turn be attached to a carrier, in one example,
a stainless steel carrier that may be attached a replaceable print
apparatus component (or in some examples, the lid of a print agent
supply cartridge). A flex circuit attached to the carrier may form
a connection between the first and second logic circuits described
above.
[0279] In one example, a sensor read sequence may comprise
selecting a sensor type (e.g. a fluid level sensor), a sensor cell
location (e.g. position in a string of sensor cells, for example by
reference to an address), setting a heating time and reading a
result. In some examples, the result may be output to an A/D
converter, which may start a conversion cycle at a predetermined
time after heating begins, for example as measured by a timer. In
some examples, the heating period and the reading period
(conversion period) may at least partially overlap, although in
other examples, reading may begin after the heating period has
expired. In one example, the reading period starts during the
heating period, and the heating period and the reading period
terminate at substantially the same time. In some examples, the
heating period and the reading period (conversion period) may at
least partially overlap, although in other examples, reading may
begin after the heating period has expired. This may allow a
temperature condition to stabilise before a reading is taken and/or
avoid heating currents which may be inconsistent along the length
of the sensor 2000 during the time that the heater elements are
powered. While measurements are taken in association with heating
in this example, heating may be absent or disabled when measuring
some sensor types.
[0280] FIG. 20B shows examples of two sets of readings for an empty
ink cartridge, comprising a set of readings 2020 taken when the
sensor cells were not heated, and a set of readings 2022 taken when
the sensor cells were heated. As discussed above, calibrating
unheated sensors to a relatively low count provides the `headroom`
for acquiring heated readings. Alternatively, heated sensors may be
calibrated to a relatively high count to provide the `headroom` for
acquiring unheated readings.
[0281] FIG. 20C shows examples of readings taken by the fluid level
sensor 2000, with the sensors cells 2006 being heated by heat
pulses supplied by the heating elements 2008. A set of readings
2024 for an empty cartridge and a set of readings for a partly
filled cartridge 2026 are shown. These readings overlap for the
lower indexed sensor positions. A projection of the expected count
returned by the lower indexed sensor for a full cartridge 2028 is
also shown
[0282] When a fluid cools the region surrounding a sensor cell
2006, such a cell 2006 heats more slowly and cools more quickly
than when such a cell 2006 is surrounded by air, in some examples
reaching a lower temperature over the duration of the heating.
Cooler elements may have a lower resistance than the hotter
elements. This results in a reduction in sensor count output by the
analogue to digital converter 2010. Thus the `step change` shown in
the transfer from a higher general count range to a lower general
count range is indicative of the ink level, as indicated by the
arrow with "ink level". The sensor(s) over which the change occurs
provides the height of the fluid level. This step change may for
example be detected by the print apparatus in which the sensor is
installed.
[0283] Block 1914 of FIG. 19A may comprise returning a data
response to a request for data indicative of a print material
level. In some examples, the number of data readings request and/or
returned in reading a fluid level sensor may be equal to the number
of level sensor cells 2006. However, in other examples, the number
of data readings may be less than the total number of sensor cells
2006, as a subset of the sensors may be read. In some examples, the
data response may be returned following receipt of a read request
from the print apparatus in which the sensor is installed.
[0284] A fluid level sensor may be queried in one or a series of
requests in order return a data response comprising a data set
which is representative of the sensor readings which, when taking
the sensor cells in their physical order provide in which a step
change in a series of data values is indicative of a measured or
estimated print agent fluid level. In some such examples, methods
may comprise generating a first data response in which a step
change in a series of data values is indicative of a measured or
estimated print agent fluid level. This may be generated by
providing an array of thermal sensors or in some other way, for
example to provide a `backwards compatible` print agent fluid
indication to a print apparatus, where the actual determination of
the fluid level is done in some other way. Such a step change may
be detected by a print apparatus performing a first derivative
calculation on the sensor responses in sequence to identify the
step change or discontinuity which indicates the fluid/air
position.
[0285] As is further set out below, block 1916 of FIG. 19A may
comprise, in at least some states of the print apparatus component,
returning a data response comprising a data set which is
representative of the sensor readings which, when taking the sensor
cells in their physical order provide a series of data values
indicative of a relatively smooth change in data values (or does
not comprise such a step change). In some examples, the rate of
change of data values may consistently increase or consistently
decrease across the series.
[0286] Thus, in one example, the first data response may comprise a
step change, and the second data response may not (or vice
versa).
[0287] In some examples, the sensors may be read `in order` of
their physical arrangement, however in other examples the sensors
may be read out of order, for example in an order specified in one
or more commands sent from the print apparatus.
[0288] FIG. 21A shows an example of a pressure event sensor 2102 in
association with a circuitry package 2104.
[0289] In this example, the pressure event sensor comprises a
plurality of pressure sensors, in this example strain sensing cells
2106 arranged over the surface of a print material container 2108.
Although in this example, only 5 cells 2106 are shown, in other
examples there may be more, for example in the region of 100-200,
for example around 120 cells (in one example, 126 cells). The
strain sensing cells 2106 may comprise piezo-resistive cells (for
example, thin film elements), the resistance of which may change
when strain is applied. The print material container 2108 comprises
an air inlet 2110, through which pressurized air may be introduced.
When the print material container 2108 is pressurized, the surface
deforms and the strain sensors placed under strain. In some
examples, in order to test the operation of the pressure event
sensor 2102, a pressure bag 2112 inside the container 2108 is
`hyper inflated` in order to cause a significant deflection in the
strain sensors (and in some examples to cause priming or purging of
nozzles or the like). In one example, the strain sensors are
implant resistors which experience a change in resistance when bent
or deflected.
[0290] While the circuitry package 2104 is shown separately from
the print material container 2108 in the example, it may be
integral (or in some examples, partially internal) thereto.
[0291] In other examples, other sensors can be used to detect a
pressurization in the container. For example, a pressure sensor
responsive to a pressure increase in the reservoir, for example
above a certain threshold (e.g. 7 kPA gauge) may be used to detect
hyperinflation/prime event.
[0292] In other examples, pressure events may be detected by
detecting airflow through a valve, and/or for example near the air
inlet 2110. For example, this may be detected using a metal slug in
an inductor, for example in the form of a Linear Variable
Differential Transformer which is pneumatically coupled to an air
inlet, using a diaphragm with a strain gauge, using a manometer
with a conductive liquid and electrical contacts that are wetted
when air pressure is applied at an input port, using a magnetic
slug in a tube with a Hall sensor outside the tube, using a
manometer with an opaque liquid and a through beam optical sensor,
using a diaphragm or slug connected to a switch, for example a Reed
switch, which can detect displacement of the diaphragm/slug, or the
like.
[0293] FIG. 21B shows readings taken from a subset of available
strain sensing cells 2106.
[0294] When unstressed, the readings may be expected to be around
250 counts. In this example, one end of the surface over which the
strain sensing cells are arranged is not constrained. Thus, the
strain sensors do not tend to change significantly, however much
pressure is applied. In this example, due the nature of the way in
which the strain sensing cells 2106 are mounted, they experience a
variable degree of strain even in the absence of pressure for
inflation of the bag. However, this need not be the case in all
examples--if all strain sensing cells 2106 were unstressed unless
the bag pressure 2112 is inflated, then a flatter curve or line
would be seen for the unpressurised measurements.
[0295] In some examples, the air pressure reached is independent of
fluid level. As such, a low on fluid supply may require more air to
be pumped into the supply to reach a target pressure, while a full
supply will require less air. However, in other examples, the air
pressure reached may depend on the state of a print agent cartridge
on which the sensor is installed. For example, the maximum pressure
reached may be higher when a cartridge is relatively full than when
the cartridge is relatively empty.
[0296] FIG. 21B shows different levels of pressurization and the
associated deflection in `inches of water` in a water column. 27.7
inches of water column (wc) pressure is equivalent to 1 PSI of
pressure (thus 50 inches of water is equivalent to 1.805 PSI, 100
inches of water is equivalent to 3.619 PSI, or around 24952 Pascal)
and 150 inches of water is equivalent to 5.415 PSI or around 37335
Pascal), or 1 inch of water is a pressure of 2.4884 mbar. The
pressures shown are absolute pressures.
[0297] In some examples, the calibration may take place to ensure
that all the sensors provide an output count of at least 200 in the
absence of a hyperinflation. This allows sufficient `headroom` for
the higher recorded pressure events without signal clipping. In
some examples, the calibration may be carried out to provide a
target count of above 250, or above 230). The sensor cell which is
expected to be under the least strain (or at least under a
relatively low strain) may be selected for testing. In some
examples, the target count value may between 225 and 245, and the
Vdac offset may be adjusted until this value is achieved.
[0298] In some examples, calibration may take place during a
pressurisation event. In such examples, it may be intended that the
test result is in a range which is below a threshold value (for
example, in this case, below 180, or below 150, or below 100). The
sensor which is expected to be under the most strain (or at least
under a relatively high strain) may be selected for testing.
[0299] Block 1916 of FIG. 19A may comprise returning a second data
response to a request for data indicative of a pressurization
event, in some examples following receipt of a read request from
the print apparatus in which the sensor is installed. In some
examples, the response to the pressurization event may be
characterised by acquiring a number or data readings, wherein the
number of data readings may be equal to the number of strain
sensing cells 2106. However, in other examples, the number of data
readings may be less than the total number of strain sensing cells
2106, as a subset of the sensors may be read.
[0300] In some examples, if a pressurization event occurs in use
and an expected behaviour is not seen (e.g. there are no readings
below a threshold), this may indicate that the pressurization event
has failed (for example, the integrity of the pressure bag 2112 has
failed).
[0301] In some examples, the method of FIG. 19A comprises detecting
a pneumatic stimulus, and providing a data response following
detection of the pneumatic stimulus. In some examples, this may be
detected as an air flow or the like. In some such examples, the
method may comprise generating a data response which is similar in
form to the expected response (e.g. in this example, a sequence of
relatively smoothly changing counts in the range of 250 to around
100 counts). While this may be generated as set out in relation to
FIGS. 21A and 21B, in other examples, for example to provide
`backwards compatibility` to a print apparatus, where the actual
determination of the count level is done in some other way. For
example, some print cartridges need not pressurise in the same way
and in such examples a response to pressurisation could be
mimicked, even in the absence of a pressurisation event (or
independently of the measurement thereof).
[0302] In other examples, the method may comprise determining
whether a request for data is a request for data indicative of a
read result from a particular strain sensor.
[0303] Examples in the present disclosure can be provided as
methods, systems or machine-readable instructions, such as any
combination of software, hardware, firmware or the like. Such
machine readable instructions may be included on a machine readable
storage medium (including but is not limited to disc storage,
CD-ROM, optical storage, etc.) having machine readable program
codes therein or thereon.
[0304] The present disclosure is described with reference to flow
charts and block diagrams of the method, devices and systems
according to examples of the present disclosure. Although the flow
diagrams described above show a specific order of execution, the
order of execution may differ from that which is depicted. Blocks
described in relation to one flow chart may be combined with those
of another flow chart. It shall be understood that at least some
blocks in the flow charts and block diagrams, as well as
combinations thereof can be realized by machine readable
instructions.
[0305] The machine readable instructions may, for example, be
executed by a general purpose computer, a special purpose computer,
an embedded processor or processors of other programmable data
processing devices to realize the functions described in the
description and diagrams. In particular, a processor or processing
circuitry may execute the machine readable instructions. Thus
functional modules of the apparatus and devices (for example, logic
circuitry and/or controllers) may be implemented by a processor
executing machine readable instructions stored in a memory, or a
processor operating in accordance with instructions embedded in
logic circuitry. The term `processor` is to be interpreted broadly
to include a CPU, processing unit, ASIC, logic unit, or
programmable gate array etc. The methods and functional modules may
all be performed by a single processor or divided amongst several
processors.
[0306] Such machine readable instructions may also be stored in a
machine readable storage (e.g. a tangible machine readable medium)
that can guide the computer or other programmable data processing
devices to operate in a specific mode.
[0307] Such machine readable instructions may also be loaded onto a
computer or other programmable data processing devices, so that the
computer or other programmable data processing devices perform a
series of operations to produce computer-implemented processing,
thus the instructions executed on the computer or other
programmable devices realize functions specified by block(s) in the
flow charts and/or in the block diagrams.
[0308] Further, the teachings herein may be implemented in the form
of a computer software product, the computer software product being
stored in a storage medium and comprising a plurality of
instructions for making a computer device implement the methods
recited in the examples of the present disclosure.
[0309] While the method, apparatus and related aspects have been
described with reference to certain examples, various
modifications, changes, omissions, and substitutions can be made
without departing from the spirit of the present disclosure. It is
intended, therefore, that the method, apparatus and related aspects
be limited only by the scope of the following claims and their
equivalents. It should be noted that the above-mentioned examples
illustrate rather than limit what is described herein, and that
those skilled in the art will be able to design many alternative
implementations without departing from the scope of the appended
claims. Features described in relation to one example may be
combined with features of another example.
[0310] The word "comprising" does not exclude the presence of
elements other than those listed in a claim, "a" or "an" does not
exclude a plurality, and a single processor or other unit may
fulfill the functions of several units recited in the claims.
[0311] The features of any dependent claim may be combined with the
features of any of the independent claims or other dependent
claims.
In some examples, the disclosure comprises any of the following
Statements.
STATEMENTS
[0312] 1. A logic circuitry package having a first address and
comprising a first logic circuit,
[0313] wherein the first address is an I2C address for the first
logic circuit, and wherein the package is configured such that, in
response to a first command indicative of a task and a first time
period sent to the first address, the first logic circuit is to,
for a duration of the time period:
[0314] (i) perform a task, and
[0315] (ii) disregard I2C traffic sent to the first address.
2. The logic circuitry package of Statement 1 wherein the first
logic circuit further comprises a timer to measure the time period.
3. A logic circuitry package according to Statement 2 wherein the
task performed by the logic circuitry package comprises at least
one of: monitoring the timer and performing a computational task
having a completion time which exceeds the time period. 4. A logic
circuitry package according to any preceding Statement wherein the
package is for association with a print material container. 5. A
logic circuitry package according to Statement 4 further comprising
a memory storing data representative of at least one characteristic
of the print material container. 6. A logic circuitry package
according to any preceding Statement wherein the package comprises
a second logic circuit and the package is configured to make the
second logic circuit accessible during the time period. 7. A logic
circuitry package according to Statement 6 wherein the package
comprises a dedicated signal path between the first and second
logic circuit and the second logic circuit is made accessible by
the first logic circuit sending a signal via the dedicated signal
path. 8. A logic circuitry package according to Statement 7 wherein
the signal is present for the duration of the time period. 9. A
logic circuitry package according to any preceding Statement which
comprises at least one sensor or sensor array. 10. A logic
circuitry package according to Statement 9 wherein the at least one
sensor comprises at least one print material level sensor. 11. A
logic circuitry package according to any preceding Statement
wherein the package has at least one second address and is
configured such that, in response to the first command, the package
is accessible via a second address for the duration of the time
period. 12. A logic circuitry package according to Statement 11
wherein the package is configured to provide a first set of
responses in response to instructions sent to the first address and
to provide a second set of responses in response to instructions
sent to a second address. 13. A logic circuitry package according
to Statement 11 or Statement 12 wherein the package is configured
to operate in a first mode in response to instructions sent to the
first address and to operate in a second mode in response to
instructions sent to the second address. 14. A logic circuitry
package according to any of Statements 11 to 13 wherein the package
is configured to provide a cryptographically authenticated set of
responses in response to cryptographically authenticated
communications sent to the first address and to provide a second,
not cryptographically authenticated, set of responses in response
to communications sent to the second address. 15. A logic circuitry
package according to any of Statements 11 to 14 which is configured
to transmit, outside of said time period and in response to
communications sent to the first address, print material
level-related data that is authenticated using an encryption key,
and which is further configured to transmit, during the time period
and in response to communications sent to the second address, print
material level-related data not authenticated using that key. 16. A
logic circuitry package according to any of Statements 11 to 15
wherein the at least one second address is an address of a second
logic circuit. 17. A logic circuitry package according to any of
Statements 11 to 16 wherein the package is not accessible via the
second address for a second time period preceding the first time
period and/or for a third time period following the first time
period. 18. A logic circuitry package according to any of
Statements 11 to 17 configured to set the second address to an
initial second address at each start of the first time period. 19.
A logic circuitry package according to Statement 18 wherein the
package is configured to set its second address to a temporary
address in response to a command sent to the initial second
address, the command including that temporary address. 20. A logic
circuitry package according to Statement 18 or 19, wherein, on
receipt of a subsequent command indicative of a task and the first
time period sent to the first address, the logic circuitry package
is configured to have the same initial second address. 21. A logic
circuitry package according to any of Statements 11 to 20 which is
configured to: respond to commands directed to the first address
and not to commands directed to the second address outside the
first time period; and respond to commands directed to the second
address and not to commands directed to the first address during
the first time period. 22. A plurality of logic circuitry packages
according to any of Statements 11 to 21 having different first
addresses and the same second address. 23. A method comprising: in
response to a first command indicative of a task and a first time
period sent to a first address of processing circuitry via an I2C
bus [0316] (i) performing, by the processing circuitry, a task and
[0317] (ii) disregarding I2C traffic sent to the first address for
a duration of the time period, the method comprising monitoring the
time period using a timer of the processing circuitry. 24. A method
according to Statement 23 wherein the method is carried out on
processing circuitry provided on a replaceable print apparatus
component. 25. A method according to any of Statements 23 to 24,
further comprising, for the duration of the time period,
responding, by the processing circuitry, to I2C traffic sent to at
least one second address of the processing circuitry. 26. A method
according to Statement 25 wherein the first address is associated
with a first logic circuit of the processing circuitry, and the at
least one second address is associated with a second logic circuit
of the processing circuitry. 27. A method according to Statement 25
or 26 further comprising disabling access to the processing
circuitry via the at least one second address after the duration of
the time period. 28. A method according to any of Statements 25 to
27 wherein the second address is configured to be an initial second
address at the start of the first time period. 29. A method
according to Statement 28 wherein the processing circuitry is
configured to reconfigure its second address to a temporary second
address in response to a command sent to the initial second address
and including that temporary address during the first time period.
30. A method according to Statement 29, wherein, on receipt of a
subsequent command indicative of the task and the first time period
sent to the first address, the logic circuitry is configured to
have the same initial second address. 31. A method according to any
of Statements 23 to 30 wherein the processing circuitry comprises a
first logic circuit and a second logic circuit of the processing
circuitry, wherein the first logic circuit is to perform the task
and to send an activation signal to the second logic circuit for
the duration of the time period. 32. A method according to
Statement 31 wherein the method further comprises deactivating the
second logic circuit by ceasing the activation signal. 33. A method
according to Statement 31 or 32 wherein the activation signal is
sent via a dedicated signal path. 34. A method according to any of
Statements 23 to 33 wherein the task performed by the processing
circuitry is the task indicated in the first command. 35.
Processing circuitry for use with a replaceable print apparatus
component to connect to a print apparatus logic circuit
comprising:
[0318] a memory and first logic circuit to enable a read operation
from the memory and perform processing tasks, the first logic
circuit comprising a timer,
wherein the processing circuitry is accessible via an I2C bus of a
print apparatus in which the replaceable print apparatus component
is installed and is associated with a first address and at least
one second address, and the first address is an I2C address for the
first logic circuit, and wherein the first logic circuit is to
participate in authentication of the replaceable print apparatus
component by a print apparatus in which the replaceable print
apparatus component is installed; and the processing circuitry is
configured such that, in response to a first command indicative of
a task and a first time period sent to the first logic circuit via
the first address, the processing circuitry is to:
[0319] (i) perform a task, and
[0320] (ii) not respond to I2C traffic sent to the first
address
for a duration of the time period as measured by the timer. 36.
Processing circuitry according to Statement 35 wherein the
processing circuitry further comprises a second logic circuit,
wherein the second logic circuit is accessible via the I2C bus and
a second address, and the first logic circuit is to generate an
activation signal to activate the second logic circuit for the
duration of the time period. 37. Processing circuitry according to
Statement 36 wherein the processing circuitry comprises a dedicated
signal path between the first and second logic circuits for
transmitting the activation signal. 38. Processing circuitry
according to Statement 36 or 37 wherein the second logic circuit
comprises at least one sensor which is readable by a print
apparatus in which the replaceable print apparatus component is
installed via the second address. 39. Processing circuitry
according to any of Statements 36 to 38 comprising at least one
sensor which is readable by a print apparatus in which the
replaceable print apparatus component is installed via the second
address and which is not readable via the first address. 40.
Processing circuitry according to Statement 38 or 39 wherein the
sensor comprises a consumable materials level sensor. 41. A
plurality of print components each comprising a memory, wherein the
memories of different print component store different print liquid
characteristics, and each print component comprises a logic
circuitry package according to any of Statements 1 to 21 or
processing circuitry of Statements 35 to 40. 42. A print cartridge
comprising a logic circuitry package according to any of Statements
1 to 21 and having a housing that has a width that is less than a
height, wherein, in a front face, from bottom to top, a print
liquid output, an air input and a recess are provided,
respectively, the recess extending at the top, wherein I2C bus
contacts of the package are provided at a side of the recess
against an inner side of a side wall of the housing adjacent the
top and front of the housing, and comprise a data contact, the data
contact being the lowest of the I2C bus contacts. 43. A print
cartridge according to Statement 42, wherein the first logic
circuit of the package is also provided against the inner side of
the side wall. 44. A replaceable print apparatus component
including the logic circuitry package of any of Statements 1 to 21,
the component further comprising a volume of liquid, the component
having a height that is greater than a width and a length that is
greater than the height, the width extending between two sides,
wherein the package comprises interface pads, and the interface
pads are provided at an inner side of one of the sides facing a
cut-out for a data interconnect to be inserted, the interface pads
extending along a height direction near the top and front of the
component, and a data pad is a bottom-most of the interface pads,
the liquid and air interface of the component being provided at the
front on the same vertical reference axis parallel to the height
direction wherein the vertical axis is parallel to and distanced
from the axis that intersects the interface pads. 45. A replaceable
print apparatus component according to Statement 44 wherein the
rest of the logic circuitry package is also provided against the
inner side. In some examples, the disclosure comprises any of the
following Paragraphs
PARAGRAPHS
[0321] 1. A logic circuitry package configured to be addressable
via a first address and at least one second address and comprising
a first logic circuit,
[0322] wherein the first address is an address for the first logic
circuit, wherein the package is configured such that:
in response to a first command indicative of a first command time
period sent to the first address, the package is accessible via at
least one second address for a duration of the first command time
period; and in response to a second command indicative of a second
command time period sent to the first address, the first logic
circuit is to, for a duration of the second command time period,
disregard traffic sent to the first address. 2. A logic circuitry
package according to Paragraph 1 wherein the first logic circuit
comprises a timer wherein the first command time period and/or
second command time period are measured by the timer. 3. A logic
circuitry package of Paragraph 1 or Paragraph 2 wherein, in
response to the second command the logic circuit is configured to
perform a processing task during at least the first or second
command time period. 4. A logic circuitry package according to
Paragraph 3 wherein the processing task comprises at least one of:
monitoring a timer and performing a computational task having a
completion time which exceeds the first command time period and/or
second command time period. 5. A logic circuitry package according
to any preceding Paragraph wherein the second command time period
is longer than the first command time period and the first logic
circuit is to, in response to the second command, not respond to
traffic sent to the first address for the duration of the second
command time period. 6. A logic circuitry package according to any
preceding Paragraph wherein the package is for association with a
print material container. 7. A logic circuitry package according to
Paragraph 6 further comprising a memory storing data representative
of at least one characteristic of the print material container. 8.
A logic circuitry package according to any preceding Paragraph
wherein the package comprises a second logic circuit and the
package is configured to make the second logic circuit accessible
during the first command time period. 9. A logic circuitry package
according to Paragraph 8 wherein the package comprises a dedicated
signal path between the first and second logic circuit and the
second logic circuit is made accessible by the first logic circuit
sending a signal via the dedicated signal path. 10. A logic
circuitry package according to Paragraph 9 wherein the signal is
present for the duration of the first command time period. 11. A
logic circuitry package according to any preceding Paragraph which
comprises at least one sensor or at least one sensor array. 12. A
logic circuitry package according to Paragraph 11 wherein the at
least one sensor or at least one sensor array comprises at least
one print material level sensor. 13. A logic circuitry package
according to any preceding Paragraph wherein the package is
configured such that, in response to the second command, the
package is accessible via a second address for the duration of the
second command time period. 14. A logic circuitry package according
to Paragraph 13 wherein the package is configured to provide a
first set of responses in response to instructions sent to the
first address and to provide a second set of responses in response
to instructions sent to a second address. 15. A logic circuitry
package according to Paragraph 13 or 14 wherein the package is
configured to operate in a first mode in response to instructions
sent to the first address and to operate in a second mode in
response to instructions sent to the first address. 16. A logic
circuitry package according to any of Paragraphs 13 to 15 wherein
the package is configured to provide a cryptographically
authenticated set of responses in response to cryptographically
authenticated instructions sent to the first address and to provide
a second, not cryptographically, authenticated set of responses in
response to instructions sent to the second address. 17. A logic
circuitry package according to any of Paragraphs 13 to 16 wherein
the second address is an address of the second logic circuit. 18. A
logic circuitry package according to any of Paragraphs 13 to 17
wherein the package is not accessible via the second address for a
time period preceding the first command time period and/or for a
time period following the first command time period. 19. A logic
circuitry package according to any of Paragraphs 13 to 18 wherein
the second address is configured to be an initial second address at
the start of the first command time period. 20. A logic circuitry
package according to Paragraph 19 wherein the package is configured
to reconfigure its second address to a temporary address in
response to a command sent to the initial second address and
including that temporary address during the first command time
period. 21. A logic circuitry package according to Paragraph 19 or
20, wherein, on receipt of a subsequent command indicative of the
first command time period sent to the first address, the logic
circuitry package is configured to have the same initial second
address. 22. A logic circuitry package according to any preceding
Paragraph which is configured to: respond to commands directed to
the first address and not to commands directed to a second address
outside the first command time period; and respond to commands
directed to a second address and not to commands directed to the
first address during the first command time period. 23. A plurality
of logic circuitry packages according to any of Paragraphs 13 to 22
having different first addresses and the same second address. 24. A
plurality of logic circuitry packages according to Paragraph 23
storing different data representative of at least one
characteristic of different print material containers. 25. A method
comprising: in response to a first command indicative of a first
command time period sent to a first address of processing circuitry
via an I2C bus, enabling, by the processing circuitry, access
thereto via at least one second address for a duration of the first
command time period; and
[0323] in response to a second command indicative of a second
command time period sent to the first address via the I2C bus, and
for a duration of the second command time period, ignoring I2C
traffic sent to the first address;
[0324] the method further comprising monitoring at least one of the
first and second command time period using a timer of the
processing circuitry.
26. A method according to Paragraph 25 wherein the method is
carried out on processing circuitry provided on a replaceable print
apparatus component. 27. A method according to Paragraph 25 or 26
wherein in response to the second command, the processing circuitry
is to perform a task. 28. A method according to Paragraph 27
wherein the task is a task indicated in the second command. 29. A
method according to any of Paragraphs 25 to 28, further comprising,
for the duration of the first command time period, responding, by
the processing circuitry, to I2C traffic sent to the at least one
second address of the processing circuitry. 30. A method according
to Paragraph 29 wherein the first address is associated with a
first logic circuit of the processing circuitry, and the at least
one second address is associated with a second logic circuit of the
processing circuitry. 31. A method according to Paragraph 30
further comprising disabling access to the processing circuitry via
the at least one second address after the duration of the first
command time period. 32. A method according to any of Paragraphs 25
to 31 wherein the second address is configured to be an initial
second address at the start of the first command time period. 33. A
method according to Paragraph 32 wherein the processing circuitry
is configured to reconfigure its second address to a temporary
address in response to a command sent to the initial second address
and including that temporary address during the first command time
period. 34. A method according to Paragraph 33, wherein, on receipt
of a subsequent command indicative of the first command time period
sent to the first address, the processing circuitry is configured
to have the same initial second address. 35. A method according to
any of Paragraphs 25 to 34 wherein the processing circuitry
comprises a first logic circuit and a second logic circuit of the
processing circuitry, wherein the method comprises, sending, by the
first logic circuit, an activation signal to the second logic
circuit for the duration of the first command time period. 36. A
method according to Paragraph 35 wherein the method further
comprises deactivating the second logic circuit by ceasing the
activation signal. 37. A method according to Paragraph 35 or 36
comprising sending the activation signal via a dedicated signal
path. 38. Processing circuitry for use with a replaceable print
apparatus component comprising:
[0325] a memory and first logic circuit to enable a read operation
from the memory and perform processing tasks, the first logic
circuit comprising a timer,
wherein the processing circuitry is accessible via an I2C bus of a
print apparatus in which the replaceable print apparatus component
is installed and is associated with a first address and at least
one second address, and the first address is an I2C address for the
first logic circuit, and wherein the first logic circuit is to
participate in authentication of the replaceable print apparatus
component by a print apparatus in which the replaceable print
apparatus component is installed; and wherein the circuitry is
configured such that: in response to a first command indicative of
a first command time period sent to the first address, the
processing circuit is accessible via at least one second address
for a duration of the first command time period; and in response to
a second command indicative of a second command time period sent to
the first address, the first logic circuit is to, for a duration of
the second command time period as measured by the timer, ignore I2C
traffic sent to the first address. 39. Processing circuitry
according to Paragraph 38 wherein the first logic circuit is
configured to be accessible via the at least one second address for
the duration of the first command time period. 40. Processing
circuitry according to Paragraph 39 wherein the processing
circuitry further comprises a second logic circuit, wherein the
second logic circuit is accessible via the I2C bus and a second
address, and the first logic circuit is to generate an activation
signal to activate the second logic circuit for the duration of the
first command time period. 41. Processing circuitry according to
Paragraph 40 wherein the processing circuitry comprises a dedicated
signal path between the first and second logic circuits for
transmitting the activation signal. 42. Processing circuitry
according to Paragraph 39 or 41 wherein the second logic circuit
comprises at least one sensor or sensor array which is readable by
a print apparatus in which the replaceable print apparatus
component is installed via the at least one second address. 43.
Processing circuitry according to Paragraph 42 in which the at
least one sensor or sensor array which is readable by a print
apparatus in which the replaceable print apparatus component is
installed via the at least one second address is not readable via
the first address. 44. Processing circuitry according to any of
Paragraphs 42 or 43 wherein the sensor comprises a consumable
materials level sensor. 45. Processing circuitry according to any
of Paragraphs 42 to 44 where, in response to the first command the
processing circuitry is to, for a duration of the first command
time period as measured by the timer, ignore I2C traffic sent to
the first address; and/or in response to the second command, the
processing circuit is accessible via at least one second address
for a duration of the first command time period. 46. A plurality of
print components each comprising a memory wherein the memories of
different print components store different print liquid
characteristics, and each print component comprises a logic
circuitry package according to any of Paragraphs 1 to 22. 47. A
print cartridge comprising a logic circuitry package according to
any of Paragraphs 1 to 22 and having a housing that has a width
that is less than a height, wherein, in a front face, from bottom
to top, a print liquid output, an air input and a recess are
provided, respectively, the recess extending at the top, wherein
I2C bus contacts of the package are provided at a side of the
recess against an inner side of a side wall of the housing adjacent
the top and front of the housing, the I2C bus contacts comprising a
data contact, the data contact being the lowest of the contacts.
48. A print cartridge according to Paragraph 47, wherein the first
logic circuit of the package is also provided against the inner
side of the side wall. 49. A replaceable print apparatus component
including the logic circuitry package of any of Paragraphs 1 to 22,
the component further comprising a volume of liquid, the component
having a height that is greater than a width and a length that is
greater than the height, the width extending between two sides, the
package comprising interface pads, wherein the interface pads are
provided at an inner side of one of the sides facing a cut-out for
a data interconnect to be inserted, the interface pads extending
along a height direction near the top and front of the component,
and comprising a data pad, the data pad being the bottom-most of
the interface pads, the liquid and air interface of the component
being provided at the front on the same vertical reference axis
parallel to the height direction wherein the vertical axis is
parallel to and distanced from the axis that intersects the
interface pads. 50. A replaceable print apparatus component
according to Paragraph 49 wherein the rest of the logic circuitry
package is also provided against the inner side. In some examples,
the disclosure comprises any of the following Clauses:
CLAUSES
[0326] 1. A method comprising, by logic circuitry associated with a
replaceable print apparatus component,
[0327] responding to a first validation request sent via an I2C bus
to a first address associated with the logic circuitry with a first
validation response; and
[0328] responding to a second validation request sent via the I2C
bus to a second address associated with the logic circuitry with a
second validation response.
2. A method according to Clause 1 wherein the first validation
response comprises a cryptographically authenticated response. 3. A
method according to Clause 2 wherein the logic circuitry stores
print apparatus component characteristics data and a first key for
cryptographic authentication of data being communicated, wherein
the first key is related to a second key for cryptographic
authentication stored on the print apparatus, and the
cryptographically authenticated response includes the
characteristics data encrypted using the first key, and at least
one of a message authentication code and a session key identifier
derived from the at least one of the first key and the second key.
4. A method according to Clause 3 wherein the second validation
response comprises a bitstream that is not encrypted using the
first key and not accompanied by a message authentication code
and/or a session key identifier. 5. A method according to any of
Clauses 2 to 4 wherein the first, cryptographically authenticated,
response, authenticated using a key, in response to a
cryptographically authenticated command via the first address,
includes data that after decoding will be represented or used as
print material level data by a receiving print apparatus logic
circuit, and
[0329] another response, not authenticated using the key, in
response to a command received via the second address, also
includes data that after decoding will be represented or used as
print material level data by the receiving print apparatus logic
circuit.
6. A method according to any preceding Clause wherein the second
validation response comprises an unencrypted response. 7. A method
according to any preceding Clause wherein the second validation
request comprises a request for an indication of a clock speed of a
timer of the logic circuitry, and the method comprises determining
a clock speed of the logic circuitry relative to another measurable
clock signal or cycle. 8. A method according to any preceding
Clause further comprising, after receiving the first validation
request, receiving an address setting signal, sent via the I2C bus
to an initial second address associated with the logic circuitry,
wherein the address setting signal is indicative of a temporary
second address, and setting the temporary second address as the
address of the logic circuitry. 9. A method according to Clause 8
wherein the initial address is a default address to be used before
each occasion on which a temporary address is set. 10. A method
according to any preceding Clause which comprises determining the
second validation response by reading a memory of the logic
circuitry to provide an indication of version identity. 11. A
method according to any preceding Clause comprising determining the
second validation response by testing at least one component of the
logic circuitry to return a test result. 12. A method according to
any preceding Clause comprising determining the second validation
response by reading a memory of the logic circuitry to provide an
indication of a number of sensors in at least one sensor class. 13.
A method according to any preceding Clause comprising determining
the second validation response comprising an indication of a
read/write history of the logic circuitry. 14. A method according
to Clause 13 further comprising storing the indication of a
read/write status of the logic circuitry, and updating the stored
indication with read/write requests of the logic circuitry. 15. A
method according to Clause 14 as it depends on Clause 8, wherein
the indication is not updated when rewriting an address of the
logic circuitry to be the temporary second address. 16. A method
according to any of Clauses 14 to 15 wherein updating the
indication comprises applying a predetermined algorithmic function
to a read/write request and/or response to determine an updated
indication. 17. A method according to any of Clauses 13 to 16
wherein a plurality of indications of a read/write status are
stored in a memory, each determined using a different predetermined
algorithmic function, and wherein the second validation request
comprises a request for one of the stored indications, and the
method comprises providing the response for that indication. 18. A
logic circuitry package for a replaceable print apparatus component
which is addressable via a first address and a second,
reconfigurable, address;
[0330] wherein the package is configured to participate in a first
validation process based on communications sent to the first
address;
[0331] and to participate in a second validation process based on
communications sent to the second address.
19. A logic circuitry package according to Clause18 wherein the
logic circuitry package is I2C compatible, using I2C compatible
addresses. 20. A logic circuitry package according to Clause 18 or
19 wherein the second, reconfigurable, address is reconfigurable
between a default address and at least one different address. 21. A
logic circuitry package according to any of Clauses 18-20 wherein
the package comprises a memory comprising identification data
configured to be read via the second address. 22. A logic circuitry
package according to Clause 21 wherein the same identification data
is stored in the package so as to be read by cryptographically
authenticated communications via the first address. 23. A logic
circuitry package according to any of Clauses 18 to 22 wherein the
package comprises a memory comprising a read/write history data
portion, configured to be read via the second address. 24. A logic
circuitry package according to Clause 23 wherein the memory further
comprises at least one cell count. 25. A logic circuitry package
according to Clause 24 wherein the at least one cell count is
configured to be read via the second address. 26. A logic circuitry
package according to Clause 25 wherein the same at least one cell
count data is configured to be read by cryptographically
authenticated communications via the first address. 27. A logic
circuitry package according to any of Clauses 24-26 comprising at
least one cell or array of cells the number of which corresponds to
the stored cell count. 28. A logic circuitry package according to
any of Clauses 18 to 27 wherein the memory further stores a clock
count. 29. A logic circuitry package according to Clause 28 wherein
the clock count represents a relative or absolute clock speed of a
timer of the package. 30. A logic circuitry package according to
any of Clauses 18 to 29 wherein the logic circuitry stores print
apparatus component characteristics data and a first key for
cryptographic authentication of data being communicated, wherein
the first key is related to a second key for cryptographic
authentication stored on the print apparatus, and participating in
the first validation process comprises sending a cryptographically
authenticated response which includes the characteristics data
encrypted using the first key, and at least one of a message
authentication code and a session key identifier derived from the
at least one of the first key and the second key. 31. A logic
circuitry package according to Clause 30 which is configured to
participate in the second validation process by sending validation
responses comprising a bitstream that is not encrypted using the
first key and not accompanied by a message authentication code
and/or session key identifier. 32. A logic circuitry package
according to Clause 31, wherein the logic circuitry package is
configured to, in response to a first cryptographically
authenticated validation request to the first address, provide a
cryptographically authenticated response using the first key, in
response to a command including a time period, be responsive to
commands directed to a default second address, in response to a
command directed to a default second address, the command including
a new address, reconfigure the default second address to be a
temporary second address, in response to a second validation
request to the, reconfigured, temporary second address, provide a
response that is not cryptographically authenticated using the
first key, after the end of the time period, again respond to
commands directed to the first address. 33. A logic circuitry
package according to Clause 32 wherein, on receipt of a subsequent
command indicative of a period sent to the first address, the logic
circuitry package is configured to have the same default second
address. 34. A logic circuitry package according to Clause 32 or
Clause 33 which is configured to reset the second address to the
same default address before or at each command including the time
period. 35. A logic circuitry package according to Clause 34
comprising a first and a second logic circuit associated with the
first and second address, respectively, the package configured to
enable the second logic circuit in response to the command
including the time period, and set the initial second address at
set enabling. 36. A logic circuitry package according to any of
Clauses 32 to 34 wherein the package comprises a first operational
mode in which it responds to communication sent to the first
address and not the second address and a second operational mode in
which it responds to communications sent to the reconfigurable
address and not the first address. 37. A logic circuitry package
according to any of Clauses 24 to 36 wherein the package comprises
a first logic circuit associated with the first address and a
second logic circuit associated with the reconfigurable address.
38. A logic circuitry package according to Clause 37 configured
such that the second logic circuit is selectively enabled by the
first logic circuit. 39. A logic circuitry package according to any
of Clauses 18 to 32 wherein the first validation response includes
identification data, the package includes a second logic circuit
and the identification data pertains to the second logic circuit.
40. A logic circuitry package according to any of Clauses 18 to 39
wherein the first validation response includes identification data
and the second validation response includes the same identification
data. 41. A logic circuitry package according to any of Clauses 18
to 40 wherein the package is configured such that, in response to a
first command indicative of a task and a first time period sent to
the first address, the package is accessible via at least one
second address for a duration of the time period. 42. A logic
circuitry package according to Clause 41 comprising a timer to
measure the time period. 43. A logic circuitry package according to
Clause 42 comprising a second timer to indicate a clock speed of
the logic circuitry during the time period. 44. A print material
container validation package comprising a memory, a contact array
for connecting with a I2C bus, at least one timer, and circuitry to
provide: a first validation function, triggered by messages sent to
a first address on an I2C bus, a second validation function,
triggered by messages sent to a second address on the I2C bus. 45.
A print cartridge comprising a logic circuitry package according to
any of Clauses 18 to 43 and having a housing that has a width that
is less than a height, wherein, in a front face, from bottom to
top, a print liquid output, an air input and a recess are provided,
respectively, the recess extending at the top, the package
comprising I2C bus contacts, wherein the I2C bus contacts are
provided at a side of the recess against an inner side of a side
wall of the housing adjacent the top and front of the housing, and
the I2C bus contacts comprise a data contact, the data contact
being the lowest of the I2C bus contacts. 46. A print cartridge
according to Clause 45, wherein the logic circuit of the package is
provided against the inner side of the side wall. In some examples,
the disclosure comprises any of the following Descriptions:
DESCRIPTIONS
[0332] 1. A logic circuit comprising: a communications interface
including a data contact to communicate via a communications bus;
an enablement contact, separate from the communication interface,
to receive an input to enable the logic circuit; and at least one
memory register, comprising at least one reconfigurable address
register, wherein the logic circuit is configured, such that, when
enabled, it responds to communications sent via the communication
bus which are addressed to the address held in a reconfigurable
address register. 2. A logic circuit according to Description 1
comprising: [0333] an analogue to digital converter. 3. A logic
circuit according to Description 2 further comprising at least one
memory register to store an offset parameter and/or a gain
parameter for the analogue to digital converter. 4. A logic circuit
according to any preceding Description wherein the logic circuit
comprises at least one sensor. 5. A logic circuit according to
Description 4 wherein the at least one sensor comprises at least
one liquid level sensor. 6. A logic circuit according to
Description 4 or Description 5 wherein the at least one sensor
comprises a first sensor array and a second sensor array, wherein
the first and second sensor arrays comprise sensors of different
types. 7. A logic circuit according to any of Descriptions 4 to 6
wherein the at least one sensor comprises at least one of an
ambient temperatures sensor, a crack detector and a fluid
temperature sensor. 8. A logic circuit according to any of
Descriptions 4 to 6 comprising at least one of: at least one memory
register to store a sensor identifier; at least one memory register
to store a sensor reading; and at least one memory register to
store a number of sensors. 9. A logic circuit according to any of
Descriptions 4-8 wherein the at least one sensor is provided on a
substrate and the substrate and/or sensor have a length:width
aspect ratio, as measured along the substrate surface, of at least
20:1. 10. A logic circuit according to any preceding Description
wherein the logic circuit has a width and/or thickness of less than
1 mm. 11. A logic circuit according to any preceding Description
comprising at least one memory register to store a version
identity. 12. A logic circuit according to any preceding
Description comprising a timer. 13. A logic circuit according to
Description 12 in which the timer comprises a ring oscillator. 14.
A logic circuit according to Description 12 or 13 comprising at
least one memory to store a count of clock cycles. 15. A logic
circuit according to any of the preceding Descriptions comprising a
memory to store a value indicative of a read/write history of the
logic circuit. 16. A logic circuit according to any preceding
Description comprising logic configured to determine a value
indicative of a read/write history of the logic circuit using a
predetermined algorithmic function and/or based on predetermined
secret data. 17. A logic circuit according to any preceding
Description comprising logic configured to determine a plurality of
values indicative of a read/write history of the logic circuit
using different predetermined algorithmic function and/or based on
predetermined secret data. 18. A logic circuit according to any
preceding Description wherein the interface is an I2C interface.
19. A logic circuit according to any preceding Description wherein
the logic circuit is for association with a print material
container. 20. A replaceable print apparatus component including
the logic circuit of any preceding Description, the component
further comprising a volume of liquid, the component having a
height that is greater than a width and a length that is greater
than the height, the width extending between two sides, wherein the
logic circuit comprises interface pads, and the interface pads are
provided at an inner side of one of the sides facing a cut-out for
a data interconnect to be inserted, the interface pads extending
along a height direction near the top and front of the component,
and the interface pads comprise a data pad, the data pad being the
bottom-most of the interface pads, the liquid and air interface of
the component being provided at the front on the same vertical
reference axis parallel to the height direction wherein the
vertical axis is parallel to and distanced from the axis that
intersects the interface pads. 21. A replaceable print apparatus
component according to Description 20 wherein the rest of the logic
circuit is also provided against the inner side. 22. A logic
circuit package comprising a first logic circuit and a second logic
circuit, wherein the first logic circuit is configured to respond
to communications sent to a first address and the second logic
circuit comprises a logic circuit according to any of Descriptions
1 to 19. 23. A method comprising receiving, by logic circuitry
connected to an I2C bus, an enablement signal, wherein the
enablement signal is provided at an input which is separate to the
I2C bus, setting, by the logic circuitry, an address thereof by
writing a default address to an address memory register; receiving,
by the logic circuitry, a command addressed to the default address
and comprising a request to reset the address; setting, by the
logic circuitry, a temporary address thereof by overwriting the
default address in the address memory register; and receiving, by
the logic circuitry, a command addressed to the temporary address.
24. A method according to Description 23 comprising receiving, by
the logic circuitry, a validation request addressed to the
temporary address, the validation request comprising a request for
an indication of a clock speed of a timer of the logic circuitry;
and determining, by the logic circuitry, a clock speed of the logic
circuitry relative to another measurable clock signal or cycle and
determining a validation response based on the relative clock
speed. 25. A method according to Description 23 or 24 comprising
receiving, by the logic circuitry, a validation request addressed
to the second address, the validation request comprising a request
for an indication of version identity; and determining, by the
logic circuitry, a validation response by reading a memory of the
logic circuitry to provide an indication of version identity. 26. A
method according to any of Descriptions 23 to 25 comprising
receiving, by the logic circuitry, a validation request addressed
to the second address, the validation request comprising a request
for an indication of version identity; and determining, by the
logic circuitry, a validation response by testing at least one
component of the logic circuitry to return a test result. In some
examples, the disclosure comprises any of the following Items:
ITEMS
[0334] 1. A logic circuitry package configured to communicate with
a print apparatus logic circuit, wherein the logic circuitry
package is configured to respond to communications sent to a first
address and to at least one second address, and the logic circuitry
package comprises a first logic circuit, wherein the first address
is an address for the first logic circuit, and the package is
configured such that, in response to a first command indicative of
a task and a first time period sent to the first address, the
package is accessible via at least one second address for a
duration of the time period. 2. A logic circuitry package according
to Item 1 wherein the package is for association with a print
material container. 3. A logic circuitry package according to Item
2 further comprising a memory storing data representative of at
least one characteristic of the print material container. 4. The
logic circuitry package according to any preceding Item that is
configured to be I2C compatible and wherein at least of the first
and second addresses are I2C compatible addresses. 5. A logic
circuitry package according to any preceding Item wherein the
package is not accessible via the second address for a second time
period preceding the first time period and/or for a third time
period following the first time period. 6. A logic circuitry
package according to any preceding Item which is configured to:
respond to communications sent to the first address and not to
communications sent to the second address(es) outside the first
time period; and respond to communications sent to the second
address(es) and not to communications sent to the first address
during the first time period. 7. A logic circuitry package
according to any preceding Item configured to set the second
address to an initial second address at each start of the first
time period. 8. A logic circuitry package according to Item 7
wherein the package is configured to set its second address to a
temporary address in response to a command sent to the initial
second address, the command including that temporary address. 9. A
logic circuitry package according to Item 7 or 8, wherein, on
receipt of a subsequent command indicative of the task and the
first time period sent to the first address, the logic circuitry
package is configured to have the same initial second address. 10.
A logic circuitry package according to any preceding Item wherein
the first logic circuit is to perform the task for the duration of
the time period. 11. A logic circuitry package according to Item 10
in which the task comprises at least one of: activating the second
address, deactivating the first address, transmitting a signal to
another logic circuit of the package, re-configuring the initial
second address to a different, temporary second address, performing
a computational task, and monitoring a timer of the first logic
circuit. 12. A logic circuitry package according to any preceding
Item wherein the first logic circuit comprises a timer to measure
the duration of the time period. 13. A logic circuitry package
according to any preceding Item wherein the first logic circuit is
configured to not respond to commands sent to the first address for
the duration of the time period. 14. A logic circuitry package
according to any preceding Item wherein the package is configured
to operate in a first mode in response to communications sent to
the first address and to operate in a second mode in response to
communications sent to the second address. 15. A logic circuitry
package according to any preceding Item wherein the package is
configured to provide a cryptographically authenticated set of
responses in response to cryptographically authenticated
communications sent to the first address and to provide a second,
not cryptographically authenticated, set of responses in response
to communications sent to the at least one second address. 16. A
logic circuitry package according to any preceding Item further
comprising a second logic circuit, wherein the second address is an
address of the second logic circuit. 17. A logic circuitry package
according to Item 16 wherein the second logic circuit includes at
least one of a non-volatile memory, a plurality of registers, a
timer, and read and/or write buffers. 18. A logic circuitry package
according to Item 16 or 17 wherein the second logic circuit
comprises at least one sensor or sensor array. 19. A logic
circuitry package according to any of Items 16 to 18 wherein the
package comprises a dedicated signal path between the first and
second logic circuit, and the at least one second address is
enabled by the first logic circuit sending a signal via the
dedicated signal path and wherein the package is configured to
activate the second logic circuit in response to the first command.
20. A logic circuitry package according to Item 19 wherein the
signal is present for the duration of the time period. 21. A logic
circuitry package according to any preceding Item which comprises
at least one sensor or sensor array. 22. A logic circuitry package
according to Item 20 wherein the at least one sensor or sensor
array comprises at least one of a print material level sensor and
another sensor type. 23. A logic circuitry package according to any
preceding Item which is configured to transmit, outside of said
time period and in response to communications sent to the first
address, communications that are authenticated using a key, and
which is further configured to transmit, during said time period
and in response to communications sent to the second address,
communications which are not authenticated using that key. 24. A
logic circuitry package according to any preceding Item which is
configured to transmit, outside of said time period and in response
to communications sent to the first address, print material
level-related data that is authenticated using an key, and which is
further configured to transmit, during said time period and in
response to communications sent to the second address,
print-material level-related data not authenticated using that key,
wherein print-material level-related data is data that the print
apparatus logic circuit interprets and represents as print material
level of a print component to which the logic circuitry package
pertains. 25. A logic circuitry package according to Item 23 or 24
wherein the key is an encryption key and/or a secret base key. 26.
A replaceable print apparatus component including the logic
circuitry package of any preceding Item, the component further
comprising a volume of liquid, the component having a height that
is greater than a width and a length that is greater than the
height, the width extending between two sides, and wherein: the
package comprises interface pads for communicating with the print
apparatus logic circuit and the interface pads are provided at an
inner side of one of the sides facing a cut-out for a data
interconnect to be inserted, the interface pads extending along a
height direction near a top and front of the component, and the
interface pads comprising a data pad, the data pad being a
bottom-most of these interface pads, and the liquid and air
interface of the component is provided at the front on the same
vertical reference axis parallel to the height direction wherein
the vertical axis is parallel to and distanced from the axis that
intersects the interface pads. 27. A replaceable print apparatus
component according to Item 26 wherein the rest of the logic
circuitry package is also provided against the inner side. 28. A
plurality of packages according to any of Items 1 to 25 having
different first addresses and the same second address. 29. A
replaceable print apparatus component including an I2C compatible
logic circuitry package, wherein the I2C compatible logic circuitry
package comprises: an I2C interface including a data contact to
communicate via an I2C bus of a host print apparatus; a memory
comprising data representing print liquid characteristics, the data
retrievable and updatable via the data contact; wherein the package
is configured to transmit data including said data representing
print liquid characteristics to the bus over the data contact; and
wherein the package is further configured to, in response to a
command indicative of a first time period sent to a first address,
subsequently respond to commands sent to at least one second
address for a duration of the time period over the same bus and
data contact; and after the end of the time period, again respond
to commands transmitted to the first address over the same bus and
data contact. 30. A replaceable print apparatus component according
to Item 29, wherein the command is also indicative of a task. 31. A
replaceable print apparatus component according to Item 29, wherein
the second address includes an initial second address, and the
package is configured to, in response to a command to the initial
second address including a temporary address, respond to data sent
to the temporary address until the end of the time period over the
same bus and data contact. 32. A print cartridge comprising an I2C
compatible logic circuitry package according to any of Item 1 to 25
and having a housing that has a width that is less than a height,
wherein, in a front face, from bottom to top, a print liquid
output, an air input and a recess are provided, respectively, the
recess extending at the top, wherein I2C bus contacts of the
package are provided at a side of the recess against an inner side
of a side wall of the housing adjacent the top and front of the
housing, the data contact being the lowest of the contacts. 33. A
print cartridge according to Item 32, wherein the first logic
circuit of the package is also provided against the inner side of
the side wall. 34. A method comprising: in response to a first
command indicative of a task and a first time period sent to a
first address of processing circuitry via a communications bus,
enabling, by the processing circuitry, access thereto via at least
one second address for a duration of the time period. 35. A method
according to Item 34 wherein the method is carried out on
processing circuitry provided on a replaceable print apparatus
component. 36. A method according to Item 34 or 35 further
comprising disabling access to the processing circuitry via the
first address for the duration of the time period. 37. A method
according to Item 34 to 36 further comprising disabling access to
the processing circuitry via any second address after the duration
of the time period. 38. A method according to Items 34 to 37
further comprising monitoring the duration of the time period using
a timer of the processing circuitry. 39. A method according to any
of Items 34 to 38 wherein the first address is associated with a
first logic circuit and the second address is associated with a
second logic circuit, and method comprises performing, by the first
logic circuit, the task for the duration of the time period. 40. A
method according to any of Items 33 to 38 wherein the first address
is associated with first logic circuit and the at least one second
address is associated with second logic circuit, and wherein
enabling access to the processing circuitry via the second address
comprises activating the second logic circuit. 41. A method
according to Item 40 wherein the method comprises the first logic
circuit sending an activation signal to the second logic circuit to
activate the circuitry. 42. A method according to Item 41 wherein
the method further comprises deactivating the second logic circuit
by ceasing the activation signal. 43. A method according to any of
Item 40 to 42 comprising sending the activation signal via a
dedicated signal path. 44. A method according to any of Items 34 to
43 wherein the second address is configured to be an initial second
address at the start of the first time period. 45. A method
according to Item 44 comprising reconfiguring, by the processing
circuitry, the initial second address to a temporary address in
response to a command sent to the initial second address and
including that temporary address during the first time period. 46.
A method according to Item 44 or Item 45, wherein, on receipt of a
subsequent command indicative of the task and the first time period
sent to the first address, the processing circuitry is configured
to have the same initial second address. 47. Processing circuitry
for use with a replaceable print apparatus component comprising:
[0335] a memory and first logic circuit to enable a read operation
from the memory, wherein the processing circuitry is accessible via
an I2C bus of a print apparatus in which the replaceable print
apparatus component is installed and is associated with a first
address and at least one second address, and the first address is
an I2C address for the first logic circuit, and wherein the first
logic circuit is to participate in authentication of the
replaceable print apparatus component by a print apparatus in which
the replaceable print apparatus component is installed; and the
processing circuitry is configured such that, following receipt of
a first command indicative of a first time period sent to the first
logic circuit via the first address, the processing circuitry is
accessible via at least one second address for a duration of the
time period. 48. Processing circuitry according to Item 47, wherein
the processing circuitry further comprises a second logic circuit,
wherein the second logic circuit is accessible via the at least one
second address and wherein the second logic circuit comprises at
least one sensor which is readable by a print apparatus in which
the replaceable print apparatus component is installed via the at
least one second address. 49. Processing circuitry according to
Item 47 or 48 in which the at least one sensor which is readable by
a print apparatus in which the replaceable print apparatus
component is installed via the at least one second address is not
readable via the first address. 50. Processing circuitry according
to any of Items 47 to 49 wherein the sensor comprises a consumable
materials level sensor.
* * * * *