U.S. patent application number 12/240692 was filed with the patent office on 2009-08-13 for reducing errors in data by synchronizing operations with noiseless periods of data transmission.
This patent application is currently assigned to Apple Inc.. Invention is credited to Wei Chen, Kapil Sakariya, Wei Yao.
Application Number | 20090202002 12/240692 |
Document ID | / |
Family ID | 40938377 |
Filed Date | 2009-08-13 |
United States Patent
Application |
20090202002 |
Kind Code |
A1 |
Yao; Wei ; et al. |
August 13, 2009 |
REDUCING ERRORS IN DATA BY SYNCHRONIZING OPERATIONS WITH NOISELESS
PERIODS OF DATA TRANSMISSION
Abstract
Methods, systems, computer readable media and means for reducing
errors in data caused by noise are provided. In some embodiments of
the present invention, timing data is transferred from first
circuitry to second circuitry. From the timing data, one or both of
the first circuitry and the second circuitry detect whether noise
is present as a result of the operations of the first circuitry. If
it is detected that noise is present the second circuitry waits for
the cessation of the noise before functioning again. If it is
detected that no noise is present, the second circuitry
functions.
Inventors: |
Yao; Wei; (Freemont, CA)
; Chen; Wei; (Palo Alto, CA) ; Sakariya;
Kapil; (Sunnyvale, CA) |
Correspondence
Address: |
ROPES & GRAY LLP
PATENT DOCKETING 39/361, 1211 AVENUE OF THE AMERICAS
NEW YORK
NY
10036-8704
US
|
Assignee: |
Apple Inc.
Cupentino
CA
|
Family ID: |
40938377 |
Appl. No.: |
12/240692 |
Filed: |
September 29, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61028483 |
Feb 13, 2008 |
|
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|
Current U.S.
Class: |
375/254 |
Current CPC
Class: |
G09G 5/00 20130101; H03K
19/0027 20130101 |
Class at
Publication: |
375/254 |
International
Class: |
H04B 14/04 20060101
H04B014/04 |
Claims
1. A method of coordinating operations of first circuitry of an
electrical device and second circuitry of the electrical device,
comprising: transferring timing data from the first circuitry to
the second circuitry; detecting a noiseless period from the timing
data; and synchronizing operations of the second circuitry to
coincide with the noiseless period.
2. The method of claim 1, wherein detecting the noiseless period
from the timing data further comprises detecting noise periods in
the timing data.
3. The method of claim 1, wherein detecting the noiseless period
from the timing data further comprises detecting the noiseless
period with the first circuitry.
4. The method of claim 1, wherein detecting the noiseless period
from the timing data further comprises detecting the noiseless
period with the second circuitry.
5. The method of claim 1, wherein detecting the noiseless period
from the timing data further comprises detecting the noiseless
period with the first circuitry and the second circuitry.
6. The method of claim 1, wherein synchronizing the operations of
the second circuitry to coincide with the noiseless period further
comprises executing the operations of the second circuitry during
the noiseless period.
7. The method of claim 2, wherein synchronizing the operations of
the second circuitry to coincide with the noiseless period further
comprises ceasing to execute the operations of the second circuitry
during the noise periods.
8. The method of claim 1, wherein the first circuitry is display
circuitry.
9. The method of claim 1, wherein the second circuitry is
touch-based input circuitry.
10. Apparatus for coordinating operations of first circuitry of an
electrical device and second circuitry of the electrical device,
comprising: display circuitry configured to: generate timing data;
transfer the timing data to one or more circuitry; and touch-based
input circuitry configured to: receive the timing data; identify a
noiseless period from the timing data; and execute an operation to
coincide with the noiseless period.
11. The apparatus of claim 10, wherein the touch-based input
circuitry is further configured to detect noise periods in the
timing data.
12. The apparatus of claim 10, wherein the display circuitry is
further configured to detect the noiseless period.
13. The apparatus of claim 11, wherein touch-based input circuitry
is further configured to cease executing one or more operations
during the noise periods.
Description
[0001] This application claims the benefit of U.S. provisional
patent application No. 61/028,483, filed Feb. 14, 2008, which is
hereby incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
Background of the Invention
[0002] This invention is directed to methods, systems, computer
readable media and means for reducing errors in data caused by
noise. More particularly, this invention relates to dynamically
calibrating the trigger point threshold of data transmissions only
during noiseless periods of data transmissions.
[0003] Liquid crystal displays (LCDs) are commonly used today in
electrical devices such as cellular phones, televisions, media
players (e.g., the iPod.TM. media player available from Apple Inc.)
and hybrid devices (e.g., the iPhone.TM. available from Apple
Inc.). LCDs are known to have several advantages over other types
of flat-panel displays (e.g., plasma displays), especially when
used in portable electrical devices. For example, LCDs require
relatively less electric power to operate and are relatively
lighter (and therefore easier to carry). As a result, LCDs are
better suited for portable electrical devices. Additionally,
because LCDs utilize a relatively higher number of pixels, LCDs
provide higher resolutions and therefore better presentations. LCDs
are also less expensive than other displays that have similar
properties.
[0004] Despite the numerous advantages of LCDs, data transmitted to
and from LCDs often contain errors. Many of the errors are a result
of noise generated by current flowing through the electrodes and
pixels of the LCD. These problems are exacerbated when LCDs are
used in portable electrical devices. More specifically, there tends
to be a further increase in the noise in data transmission due to
varying environmental factors (e.g., varying temperature, humidity,
etc.) that can affect the flow of current in the LCD. Errors in
data transmitted in a portable electrical device may adversely
affect the performance of the electrical device. For example, the
error may affect the electrical device's ability to present images
on an LCD display.
[0005] A traditional approach to reducing errors in data
transmitted between components of a handheld electrical device
involves compensating for bit biasing. The trigger point threshold
of data being transmitted determines where a bit switches from 1 to
0 and vice versa. In an ideal environment, the trigger point
threshold is an average of the high and low trigger points during
data transmission. Long strings of bits (i.e., long strings of 1's
or 0's) can produce adverse switching characteristics of data being
transmitted. To counteract these adverse switching characteristics,
some conventional systems continuously adjust the trigger point
threshold by identifying the high and low trigger points during
data transmission, and determining an average of the two points. A
major disadvantage of this approach is that it does not account for
noise that exists in the data transmission. This noise can grossly
distort the trigger point threshold, potentially rendering it too
high or too low.
[0006] The present invention solves these and other problems by
reducing errors in data transmitted in an electrical device using
the execution of tasks during noiseless intervals.
SUMMARY OF THE INVENTION
[0007] Methods, systems, computer readable media and means are
provided for executing tasks during noiseless intervals. The device
may be a portable electrical device.
[0008] In some embodiments of the invention, the operations of
various components (and the corresponding circuitry) of the device
are coordinated with noiseless periods to ensure better
functionality. Timing data is transferred from first circuitry to
second circuitry. From the timing data, one or both of the first
circuitry and the second circuitry detect whether noise is present
as a result of the operations of the first circuitry. If it is
detected that noise is present the second circuitry waits for the
cessation of the noise before functioning again. If it is detected
that no noise is present, the second circuitry functions.
[0009] Further features of the invention, its nature and various
advantages will be more apparent from the accompanying drawings and
the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The above and other features of the invention, its nature
and various advantages will be more apparent upon consideration of
the following detailed description, taken in conjunction with the
accompanying drawings in which:
[0011] FIG. 1 is a simplified elevational view of an illustrative
electrical device of the type that can benefit from the
invention;
[0012] FIG. 2 is a simplified block diagram of an illustrative
embodiment of circuitry that may be included in an electrical
device of the type shown in FIG. 1;
[0013] FIG. 3 is a simplified schematic block diagram of an
illustrative embodiment of certain components from FIG. 2 in
accordance with the invention;
[0014] FIG. 4 is a simplified schematic block diagram of a
representative portion of certain circuitry of the type shown in
FIG. 3;
[0015] FIG. 5 is a plot of several illustrative circuit traces that
are useful in explaining certain aspects of the invention;
[0016] FIG. 6 is a simplified logical flow diagram of exemplary
methods in accordance with some embodiments of the invention;
and
[0017] FIG. 7 is a plot of illustrative circuit traces that are
useful in explaining certain aspects of the invention.
DETAILED DESCRIPTION
[0018] FIG. 1 shows electrical device 100, which can be used to
implement some embodiments of the invention. Electrical device 100
can function as a media device, communications device, gaming
device, locator device, radio receiver, web-browsing device,
organization device and/or any other type of electrical device or
hybrid thereof. For example, electrical device 100 can be coupled
(wirelessly or via a wire) to a network or host device (such as a
desktop or a laptop computer), download media data files (e.g.,
music, still image and video files), play the media data files,
upload data to and communicate with a host device or network
server, organize a user's personal information (e.g., contacts,
appointments, etc.), communicate with at least one accessory or
remote device (e.g., display screen, speaker system, etc.) and/or
perform any other function. Although electrical device 100 is shown
in FIG. 1 as being an iPhone.TM., which is an example of a hybrid
device that combines various types of functionality into one
device, one skilled in the art will appreciate that electrical
device 100 can take any form and/or perform any function without
departing from the spirit of the present invention.
[0019] Electrical device 100 comprises multi-touch display
component 102. Multi-touch display component 102 can function as
both a display component and user input component. Multi-touch
display component 102 includes a transparent touch panel and a
visual display component, such as a thin film transistor (TFT) LCD.
The touch panel comprises a touch sensitive surface and is often
positioned in front of the display screen. In this manner, the
touch sensitive surface covers the viewable area of the display
screen and, in response to detecting a touch event, generates a
signal that can be processed and utilized by other components of
electrical device 100. Multi-touch display component 102 can also
include circuitry dedicated to the touch panel and/or display
component. Multi-touch display screens are discussed in more detail
in commonly assigned U.S. Patent Publication No. US 2006/0097991,
entitled "MULTIPOINT TOUCHSCREEN," which is incorporated by
reference herein in its entirety.
[0020] Multi-touch display component 102 can present interactive
displays to a user. For example, display 104 is shown in FIG. 1 and
includes a number of listings, wherein each listing is associated
with an image and text. In response to a user touching one of the
listings, one or more integrated circuits (ICs) in multi-touch
display component 102 can replace display 104 with another
interactive display (not shown). Display 104 (and any other display
presented by electrical device 100) can include various display
elements such as overlay windows, images, video, text, etc.
[0021] Electrical device 100 can also include one or more other
user interface components, such as button 106, which can be used to
supplement multi-touch display component 102. One skilled in the
art will appreciate that, regardless of what is shown in FIG. 1,
electrical device 100 can include any type of user input
component(s), such as, for example, click wheel, scroll wheel,
QWERTY keyboard, number pad, switch, etc.
[0022] Electrical device 100 can also include microphone 108 and
audio output 110, which are respective examples of other types of
input and output components. Microphone 108 and audio output 110
are shown as being integrated into electrical device 100, but one
skilled in the art will appreciate that an external device (e.g.,
headphones, wireless devices such as Bluetooth earpieces or any
other accessory device) or a connector can be used to facilitate
the receiving and playing back of audio signals and/or the audio
portion of video or other multi-media files. Additional
input/output components, such as a camera and/or haptic feedback
component, can also be integrated into and/or coupled to electrical
device 100 via the electrical device's connector component (not
shown).
[0023] Electronic circuitry 200 inside electrical device 100 may
have an overall organization like that shown in FIG. 2. Circuitry
200 may include processor 202, storage 204, memory 206, input
circuitry 208, output circuitry 210, display circuitry 212,
communications circuitry 214, power supply 216 and bus 218. One
skilled in the art will appreciate that, in some embodiments,
circuitry 200 can include more than one of each component or
circuitry, and that to avoid over-complicating the drawing, only
one of each is shown in FIG. 2. In addition, one skilled in the art
will appreciate that the functionality of certain components (and
their correspond circuitry) can be combined or omitted and that
additional components, circuitry, and connections, which are not
shown in FIG. 2, can be included in circuitry 200 without departing
from the spirit of the invention.
[0024] Processor 202 can be any type of processor such as a
processor that uses ARM architecture (e.g., Marvell's XScale or
Texas Instrument's OMAP series processors), any other processor
suitable for a portable electrical device, or any processor that
meets the needs of electrical device 100. Processor 202 can be
configured to enable electrical device 100 to perform any function
electrical device 100 is required to perform. As an example,
processor 202 may send commands to display circuitry 212 and in
response, display circuitry 212 can present a display to a user.
Processor 202 may also be used to run operating system
applications, firmware applications, media playback applications,
media editing applications and/or any other application.
[0025] Storage 204 can be one or more storage mediums including a
hard-drive, solid-state drive (e.g., NAND flash memory), other type
of non-volatile memory (such as ROM), any other suitable type of
storage component, or any combination thereof. Storage 204 may
store media data (e.g., audio and video files), application data
(e.g., for implementing functions on electrical device 100),
firmware, wireless connection information data (e.g., information
that enables electrical device 100 to establish a wireless
connection), subscription information data (e.g., information that
keeps track of podcasts or audio broadcasts or other media a user
subscribes to), contact information data (e.g., telephone numbers
and email addresses), calendar information data, any other suitable
data, or any combination thereof. The data may be formatted and
organized in one or more types of data files.
[0026] Memory 206 can include cache memory, semi-permanent or
volatile memory such as RAM, and/or one or more different types of
memory used for temporarily storing data. Memory 206 can also be
used for storing data used to operate applications electrical
device 100 is running.
[0027] Input circuitry 208 can convert (and encode/decode, if
necessary) analog signals and other signals (e.g., physical contact
inputs from a multi-touch screen and/or physical movements from a
mouse), into digital signals. The digital signals can be provided
to processor 202, storage 204, memory 206, or any other component
of circuitry 200. Although input circuitry 208 is illustrated in
FIG. 2 as a single component of circuitry 200, a plurality of input
circuitries can be included in circuitry 200. Input circuitry 208
can be used to interface with any input component, such as
microphone 108 discussed above in connection with FIG. 1. For
example, circuitry 200 can include specialized input circuitry
associated with one or more microphones, cameras, proximity
sensors, accelerometers, ambient light detectors, etc. Input
circuitry 208 can include input driver circuitry (e.g., touch
driver circuitry) and/or circuitry for driving input driver(s). As
another example, the input circuitry of a multi-touch screen can be
integrated into or coupled directly to the touch panel portion of
the multi-touch screen component of an electrical device.
[0028] Output circuitry 210 can convert (and encode/decode, if
necessary) digital signals into analog signals (analog audio
signals, analog video signals, etc.). Output circuitry 210 may
receive digital signals from processor 202 or any other component
of circuitry 200 and convert digital signals into analog signals.
Although output circuitry 210 is illustrated in FIG. 2 as a single
component of circuitry 200, a plurality of output circuitries can
be included in circuitry 200. Output circuitry 210 can be used to
interface with any output component, such as audio output 110
discussed in connection with FIG. 1. For example, electrical device
100 can include specialized output circuitry associated with output
devices such as speakers.
[0029] Display circuitry 212 is an example of specialized output
circuitry. Display circuitry 212 can accept and/or generate signals
for presenting displays (including textual, video and/or graphical
information) on a display such as multi-touch display component 102
discussed above. For example, display circuitry 212 can include a
coder/decoder (CODEC) to convert digital media data into analog
signals. Display circuitry 212 can also include display driver
circuitry and/or circuitry for driving display driver(s). The
display signals can be generated by processor 202 or display
circuitry 212. The display signals can provide media information
related to media data received from communications circuitry 214
and/or any other component of circuitry 200. In some embodiments,
display circuitry 212, like any other component discussed herein,
can be integrated into and/or electrically coupled to electrical
device 100. For example, display circuitry 212 can be integrated
into the display component of a multi-touch display component 102
and can communicate directly with processor 202 and/or input
circuitry 208.
[0030] Communications circuitry 214 can permit electrical device
100 to communicate with one or more servers or other devices using
any suitable communications protocol. For example, communications
circuitry 214 may support Wi-Fi (e.g., a 802.11 protocol),
Ethernet, Bluetooth.TM., high frequency systems (e.g., 900 MHz, 2.4
GHz, and 5.6 GHz communication systems), infrared, TCP/IP, HTTP,
BitTorrent, FTP, RTP, RTSP, SSH, any other communications protocol,
or any combination thereof.
[0031] Power supply 216 can provide power to the components of
circuitry 200. In some embodiments, power supply 216 can be coupled
to a power grid (e.g., a wall outlet, automobile cigarette lighter,
etc.). Power supply 216 can also include one or more batteries for
providing power to a portable electrical device. As another
example, power supply 216 can be configured to generate power in a
portable electrical device from a natural source (e.g., solar
cells).
[0032] Bus 218 can provide a data transfer path for transferring
data signals to, from, or between processor 202, storage 204,
memory 206, communications circuitry 214, and any other
component(s) included in circuitry 200.
[0033] In some embodiments, electrical device 100 may be coupled to
one or more other devices (not shown) for performing any suitable
operation that may require electrical device 100 and any other
device to be coupled together. Electrical device 100 may be coupled
to a host, slave, master and/or accessory device. The other device
may perform operations such as data transfers and software or
firmware updates. The other device may also execute one or more
operations in lieu of electrical device 100 when, for example,
memory 206 does not have enough memory space, or processor 202 does
not have enough processing power to perform the operations
efficiently. Alternatively, the other device may perform one or
more operations in conjunction with electrical device 100 so as to
increase the efficiency of electrical device 100. For example, if
electrical device 100 needs to perform several steps in a process,
electrical device 100 may execute some of the steps while the other
device executes the rest.
[0034] Electrical device 100 may be coupled with another device
over a communications link using any suitable approach. As an
example, the communications link may be any suitable wireless
connection. The communications link may support any suitable
wireless protocol such as, for example, Wi-Fi (e.g., a 802.11
protocol), Bluetooth.RTM., infrared, GSM, GSM plus EDGE, CDMA,
quadband, or any other suitable wireless protocol. Alternatively,
the communications link may be a wired link that is coupled to both
electrical device 100 and the other device (e.g., a wire with a USB
connector or a 30-pin connector). A combination of wired and
wireless links may also be used to couple electrical device 100
with another device.
[0035] FIG. 3 focuses somewhat more specifically on a portion of
FIG. 2, with additional elements shown (including elements in
accordance with the invention). In particular, FIG. 3 shows
processor 202 applying data signals 312 to display circuitry 212.
Display circuitry 212 controls the signals on a plurality of source
lines 306a-m and a plurality of gate lines 308a-n. (Reference
characters m and n are arbitrary index limit values.) The visual
appearance of a pixel 302 at a source-line/gate-line intersection
is controlled by the signals on those source and gate lines. Only
one representative pixel 302 is shown in FIG. 3 to avoid
over-complicating the drawing.
[0036] The circuitry associated with a typical pixel 302 is shown
in more detail in FIG. 4. There it will be seen how a gate line
signal 308 controls (via a transistor switch 404) application of a
Vsource voltage to one electrode of pixel 302. The other electrode
of pixel 302 is connected to a Vcommon (or Vcom) voltage. Pixel 302
includes red (R), green (G), and blue (B) display capability.
Again, the visual appearance of pixel 302 is controlled by the
voltage across its electrodes.
[0037] Returning to FIG. 3, data for controlling display 104 is
applied to display circuitry 212 via leads 312. Display circuitry
212 typically includes several "layers" of circuitry performing a
variety of tasks on the data signals received via leads 312. For
example, it is typically necessary for display circuitry 212 to (1)
assemble successive bytes of data from these signals, (2) look for
errors in the data, (3) minimize any such errors to the extent
possible, (4) process the data into the form suitable for
controlling display 104, and (5) actually use the processed data to
drive the display (i.e., via source and gate lines 306 and
308).
[0038] The operations described in the preceding paragraph are
typically complex operations involving large amounts of data that
must be handled at very high data rates. To facilitate such data
signaling and data handling operations, various industry-standard
data communication protocols (e.g., the Mobile Pixel Link (MPL)
protocol and the Mobile Industry Protocol Interface (MIPI)
protocol) are known. Alternatively, a generally similar customized
data communication protocol may be developed and employed. However,
even with the benefit of all of this technology, the data signals
312 received by circuitry 212 can sometimes be corrupted by noise
(electrical interference) from other sources in electrical device
100 to a degree that is beyond the error-correction capability of
circuitry 212. For example, the operation of a display component
(e.g., the flow of power through the gate and/or source lines, as
well as the charging of pixels) can result in noise that adversely
impacts data. Thus display 104 itself may constitute a noise source
in electrical device 100. As another example, transmitting data
from central processor 202 to display circuitry 212 without
satisfying timing conditions for transmission may be another source
of noise. Another source of noise may be a faulty connection
between central processor 202 and display circuitry 212. Noise may
also be created as a result of a user interaction with electrical
device 100. For example, if electrical device 100 includes a touch
screen, information transmitted from that screen to processor 202
may include noise. Typically contributing to sensitivity or
susceptibility of signals 312 to noise are the relatively low
power, low voltage swing, and high data rates of such signals.
Whatever its source, such noise that causes uncorrectable data
errors in signals 312 can result in errors in what the user sees on
display 104, and this is very undesirable.
[0039] In accordance with the present invention, display circuitry
212 is equipped with an output lead 314 on which at least certain
kinds of data errors detected by circuitry 212 are indicted (by an
error indication in an error signal) as soon as possible after
circuitry 212 has detected such a data error. Thus such an error
indication is preferably output from component 212 (on lead 314)
substantially concurrently with detection of a data error by data
signal receiving and handling circuitry of component 212. In the
embodiment shown in FIG. 3 error signal 314 is applied to processor
202. Also in this embodiment, processor 202 receives a plurality of
other input signals 320a-k (where k is an arbitrary index limit
value), each of which signals 320 may include a noise component
from a respective noise source elsewhere in electrical device 100.
Examples of possible noise sources that may supply signals 320a-k
have been identified earlier in this specification. To recapitulate
just a few of these examples, one of signals 320 may indicate power
supply noise of electrical device 100. Another of signals 320 may
indicate touch screen noise of electrical device 100. Still another
of signals 320 may indicate display noise of electrical device 100.
Others of signals 320 may indicate noise from other possible noise
sources on electrical device 100.
[0040] FIG. 5 shows an example of some noise signal waveforms that
processor 202 may receive via leads 320. Each of these waveforms is
identified by the same reference number as the lead 320 on which
that waveform is received by processor 202. The presence of noise
from a source associated with any one of signals 320 is indicated
by that signal having a higher level than otherwise. The greater
the noise from a given source, the higher the concurrent (or at
least substantially concurrent) level of the associated noise
signal 320. Thus an elevated level in any one of noise signals 320
in FIG. 5 constitutes a noise indication in that signal.
[0041] FIG. 5 also shows an example of an error signal waveform
that display circuitry 212 may output via lead 314. Again, this
error signal waveform is identified by the same reference number
(314) as the lead on which that waveform is received by processor
202. A relatively low level of signal 314 indicates no error output
indication from display circuitry 212. A high level of signal 314
indicates that display circuitry 212 has concurrently (or at least
substantially concurrently) detected an error. All of signals 320
and 314 are plotted against the same horizontal time base in FIG. 5
(earlier time to the left; later time to the right).
[0042] In the particular example shown in FIG. 5, it will be noted
that signal 314 begins (at time t1) to indicate an error in display
circuitry 212 shortly after signal 320a begins (at about time t0)
to indicate a significant amount of noise from the source
associated with signal 320a. Processor 202 detects this timing
correlation between the noise burst in signal 320a and the error
indication in signal 314, and processor 202 accordingly outputs
(via lead 330) an indication that noise from the source associated
with signal 320a may have produced the error indicated at time t1.
Others of signals 320b-k in FIG. 5 also indicate noise from their
associated sources at various other times, but these other noise
indications are not sufficiently closely correlated in time to the
t1 error indication to have been likely causes of that error
indication. Processor 202 detects this lack of correlation between
these other noises and the t1 error indication and can thereby rule
out attributing the t1 error indication to these other noise
sources. Again, the noise and error correlation is closest for the
noise burst in signal 320a, and so processor 202 identifies (via
lead 330) that noise from the source associated with signal 320a
may have caused the error at t1.
[0043] In some embodiments of the present invention, the various
components (and corresponding circuitry) of electrical device 100,
which were discussed above in connection with FIGS. 1-5, can
generate timing data based on their operations, and can transfer
the timing data to one or more other components (or corresponding
circuitry). The timing data can indicate, among other things, when
noiseless periods occur (i.e., have occurred, are occurring and/or
will be occurring). As discussed above with respect to FIGS. 1-5,
there may be noise present in the data transmitted between the
components of electrical device 100. However, there may be a period
of time, defined as a noiseless period, when the noise in data
transmission is reduced. For example, a video blanking period is a
noiseless period. A noiseless period can occur consistently at a
known frequency (e.g., 60 hz) for a set amount of time (e.g., 15
microseconds).
[0044] The timing data transferred between the various components
(and corresponding circuitry) of electrical device 100 can be
monitored to detect noiseless periods in order to coordinate the
operations of electrical device 100 with the noiseless periods.
This can ensure that the operations of electrical device 100 are
executed more efficiently.
[0045] An example of an advantage that can be realized by
coordinating the operations of electrical device 100 with noiseless
periods is shown by process 600 of FIG. 6. Process 600 shows a
method of coordinating the operations of various components (and
the corresponding circuitry) of electrical device 100 with
noiseless periods to ensure better functionality. For example
timing data can be transferred from first circuitry to second
circuitry. The first circuitry can be a source of noise (i.e.,
"noisy circuitry") that can adversely impact the functionality of
the second circuitry (i.e., "noise-sensitive circuitry"). For
example, display circuitry can be noisy circuitry while touch-based
input circuitry can be noise-sensitive circuitry.
[0046] Process 600 begins at step 602. At step 604, timing data is
transferred from the first circuitry to the second circuitry. At
step 606, either one or both of the first circuitry and the second
circuitry can detect, from the timing data, whether noise is
present as a result of the first circuitry operating. For example,
one or both of the first circuitry and the second circuitry can
detect whether the noise present exceeds a pre-set acceptable
level.
[0047] If it is detected at step 606 that noise is present, process
600 proceeds to step 608 where the second circuitry waits for the
cessation of the noise before functioning again. Process 600 then
returns to step 606 where one or both of the first and second
circuitry detect whether there is noise present. In response to
detecting at step 606 that no noise is present, process 600
proceeds to step 610. At step 610, the second circuitry functions.
For example, if the second circuitry is a touch-based circuitry, it
can enter a ready mode where it awaits for user inputs.
[0048] From step 610, process 600 proceeds to step 612 where either
one or both of the first circuitry and the second circuitry can
detect once again whether noise is present as a result of the
operations of the first circuitry. In response to detecting that no
noise is present, process 600 returns to step 610 where the second
circuitry operates. In response to detecting at step 612 that noise
is present, process 600 proceeds to step 608 where the second
circuitry waits for the cessation of the noise in order to
operate.
[0049] For example, FIG. 7 shows timing diagram 700, which is an
example of how the functionality of the second circuitry can be
coordinated based on noise generated by the first circuitry. Signal
702 represents an exemplary noise waveform associated with the
first circuitry. Signal 704 represents an exemplary waveform
associated with the functioning of the second circuitry.
[0050] For example, a noise region exists in signal 702 during the
time period between t0 and t1. Accordingly, during the time period
between t0 and t1, the second circuitry is not functioning. This is
represented by a period of inactivity in signal 704. After time t1,
the first circuitry enters a noiseless period until t2. As
discussed above, the first circuitry can send timing data to the
second circuitry, enabling the second circuitry to know when a
noiseless period is begins and when the noise period begins. In
other embodiments, the second circuitry can generate timing data
(instead of or in addition to receiving timing data from the first
circuitry).
[0051] The above is meant to be exemplary only and not limiting in
any manner. One skilled in the art will appreciate various other
advantages of the present invention that are not explicitly stated
above.
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