U.S. patent application number 09/820013 was filed with the patent office on 2002-02-07 for digital electrochromic circuit with a vehicle network.
Invention is credited to Drummond, John P., Lynam, Niall R..
Application Number | 20020014973 09/820013 |
Document ID | / |
Family ID | 26892025 |
Filed Date | 2002-02-07 |
United States Patent
Application |
20020014973 |
Kind Code |
A1 |
Drummond, John P. ; et
al. |
February 7, 2002 |
DIGITAL ELECTROCHROMIC CIRCUIT WITH A VEHICLE NETWORK
Abstract
A vehicular rearview mirror system includes an interior rearview
mirror system having an electrochromic reflective element, a
digital electrochromic drive circuit supplying a drive signal to
the reflective element and a garage door opener. The garage door
opener includes a transmitter and logic circuit. The logic circuit
supplies signals to the transmitter for transmitting garage door
opening signals. A microcontroller is provided which defines, at
least in part, the digital drive circuit and logic circuit. In this
manner, the digital electrochromic mirror system and the garage
door opener have at least some components in common. The
microcontroller communicates over a vehicle network with at least
one module performing at least one other vehicle function. The
vehicle network may have at least wired interconnections and may
further have wireless interconnections.
Inventors: |
Drummond, John P.;
(Glenageary, IE) ; Lynam, Niall R.; (Holland,
MI) |
Correspondence
Address: |
VAN DYKE, GARDNER, LINN AND BURKHART, LLP
2851 CHARLEVOIX DRIVE, S.E.
P.O. BOX 888695
GRAND RAPIDS
MI
49588-8695
US
|
Family ID: |
26892025 |
Appl. No.: |
09/820013 |
Filed: |
March 28, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60196577 |
Mar 31, 2000 |
|
|
|
Current U.S.
Class: |
340/815.4 ;
359/589; 359/884 |
Current CPC
Class: |
B60R 11/04 20130101;
B60R 1/12 20130101; B60R 2001/1215 20130101; B60R 1/088
20130101 |
Class at
Publication: |
340/815.4 ;
359/884; 359/589 |
International
Class: |
G02B 005/28 |
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A vehicular rearview mirror system, comprising: a digital
electrochromic mirror system, including a digital drive circuit and
an electrochromic reflective element, said reflective element
assuming a partial reflectance level in response to a drive signal,
said drive circuit providing a drive signal to said reflective
element; a garage door opener, including a transmitter and a logic
circuit, said logic circuit supplying signals to said transmitter
for transmitting garage door opening signals; a microcontroller
defining, at least in part, said digital drive circuit and said
logic circuit, wherein said digital electrochromic mirror system
has components in common with said garage door opener; and said
microcontroller communicating over a vehicle network with at least
one other module performing at least one other vehicle
function.
2. The vehicle rearview mirror system of claim 1 wherein said
vehicle network comprises a plurality of wired network
interconnections.
3. The vehicle rearview mirror system of claim 2 wherein said wired
network has a protocol selected from the group consisting of a LIN,
a CAN and a LAN.
4. The vehicle rearview mirror system of claim 2 wherein said
vehicle network comprises at least one of a wire, a cable and a
fiber-optic link.
5. The vehicle rearview mirror system of claim 1 wherein said
vehicle network comprises at least partially a wireless
network.
6. The vehicle rearview mirror system of claim 5 wherein said
wireless network comprises a short-range radio-frequency
network.
7. The vehicle rearview mirror system of claim 6 wherein said
wireless network at least partially follows a BLUETOOTH
protocol.
8. The vehicle rearview mirror system of claim 5 wherein said
wireless network comprises at least one of infrared
interconnections and radio-frequency interconnections.
9. The vehicle rearview mirror system of claim 1 wherein said
digital drive circuit and said logic circuit are at least partially
on a common circuit board.
10. The vehicle rearview mirror system of claim 1 including a
battery supplying power to said digital drive circuit and said
logic circuit that is separate from vehicle ignition.
11. The vehicle rearview mirror system of claim 10 wherein said
battery is rechargeable.
12. The vehicle rearview mirror system of claim 11 including a
solar power system for charging said battery.
13. The vehicle rearview mirror system of claim 1 wherein said at
least one module performing at least one other vehicle function
includes at least one additional mirror assembly including another
electrochromic reflective element that assumes a partial
reflectance level in response to another drive signal and wherein
said microcomputer supplies a partial reflectance level value to
said additional mirror assembly over said network.
14. The vehicle rearview mirror system of claim 13 wherein said
digital electrochromic mirror system comprises an interior rearview
mirror assembly and said at least one additional mirror assembly
comprises at least one exterior rearview mirror assembly.
15. The vehicle rearview mirror system of claim 14 wherein said at
least one additional mirror assembly comprises at least two mirror
assemblies and wherein said at least two mirror assemblies comprise
a driver-side exterior mirror assembly and a passenger-side
exterior mirror assembly.
16. The vehicle rearview mirror system of claim 1 wherein said at
least one module performing at least one other vehicle function
includes at least one of an instrument panel and a headlight
control circuit and wherein ambient light level information is
provided to said at least one of an instrument panel and a
headlight control circuit over said network.
17. The vehicle rearview mirror system of claim 16 wherein said
ambient light level information is developed with said digital
electrochromic mirror system.
18. The vehicle rearview mirror system of claim 1 wherein said at
least one module performing at least one other vehicle function
includes a reverse gear detection module and wherein said digital
electrochromic mirror system responds to reverse gear information
sent from said reverse gear detection module over said network to
establish a high-reflectance level of said electrochromic
reflective element.
19. The vehicle rearview mirror system of claim 1 including a
positioning system for positioning said reflective element and
wherein said at least one module performing at least one other
vehicle function includes a memory module and wherein said network
supplies memory values from said memory module to operate said
positioning system.
20. The vehicle rearview mirror system of claim 1 further including
a digital sound-processing system, wherein said digital
sound-processing system has components in common with said digital
electrochromic mirror system and said garage door opener.
21. A vehicular rearview mirror system, comprising: an interior
rearview mirror system comprising an electrochromic reflective
element, said reflective element assuming a partial reflectance
level in response to a drive signal, a housing for said an
electrochromic reflective element, and a circuit board in said
housing, a digital electrochromic drive circuit on said circuit
board, said drive circuit supplying a drive signal to said
reflective element; a garage door opener at least partially on said
circuit board, said garage door opener including a transmitter and
a logic circuit, said logic circuit supplying signals to said
transmitter for transmitting garage door opening signals; a
microcontroller defining, at least in part, said digital drive
circuit and said logic circuit, wherein said digital electrochromic
mirror system has components in common with said garage door
opener; and said microcontroller communicating over a vehicle
network with at least one module performing at least one other
vehicle function.
22. The vehicular rearview mirror system of claim 21 wherein said
vehicle network comprises at least wired network connections.
23. The vehicular rearview mirror system of claim 22 wherein said
vehicle network has a protocol selected from the group consisting
of a LIN, a CAN and a LAN.
24. The vehicular rearview mirror system of claim 23 wherein said
vehicle network comprises at least one of wire, cable and
fiber-optic.
25. The vehicular rearview mirror system of claim 21 wherein said
vehicle network is at least partially a wireless network.
26. The vehicular rearview mirror system of claim 25 wherein said
wireless network comprises a short-range network.
27. The vehicular rearview mirror system of claim 26 wherein said
wireless network has a BLUETOOTH protocol.
28. The vehicular rearview mirror system of claim 25 wherein said
wireless network comprises at least one of infrared and
radio-frequency.
29. The vehicle rearview mirror system of claim 21 including a
battery supplying power to said digital drive circuit and said
garage door opener that is separate from vehicle ignition.
30. The vehicle rearview mirror system of claim 29 wherein said
battery is rechargeable.
31. The vehicle rearview mirror system of claim 30 including a
solar system for charging said battery.
32. The vehicle rearview mirror system of claim 21 wherein said at
least one module performing at least one other vehicle function
includes at least one additional mirror assembly including another
electrochromic reflective element that assumes a partial
reflectance level in response to another drive signal and wherein
said microcomputer supplies a partial reflectance level value to
said additional mirror assembly over said network.
33. The vehicle rearview mirror system of claim 32 wherein said
digital electrochromic mirror system comprises an interior rearview
mirror system and said at least one additional mirror assembly
comprises at least one exterior rearview mirror assembly.
34. The vehicle rearview mirror system of claim 33 wherein said at
least one additional mirror assembly comprises at least two mirror
assemblies and wherein said at least two mirror assemblies comprise
a driver side exterior mirror assembly and a passenger side
exterior mirror assembly.
35. The vehicle rearview mirror system of claim 21 wherein said at
least one module performing at least one other vehicle function
includes at least one of an instrument panel and a headlight
control circuit and wherein ambient light level information is
provided to said at least one of an instrument panel and a
headlight control circuit over said network.
36. The vehicle rearview mirror system of claim 35 wherein said
ambient light level information is developed with said digital
electrochromic mirror system.
37. The vehicle rearview mirror system of claim 21 wherein said at
least one module performing at least one other vehicle function
includes a reverse gear detection module and wherein said digital
electrochromic mirror system responds to reverse gear information
from said reverse gear detection module sent over said network to
establish a high reflectance level of said electrochromic
reflective element.
38. The vehicle rearview mirror system of claim 21 including a
positioning system for positioning said reflective element and
wherein said at least one other module performing other vehicle
functions include a memory module and wherein said network supplies
memory values retrieved from said memory module to operate said
positioning system.
39. The vehicle rearview mirror system of claim 21 further
including a digital sound-processing system, wherein said digital
sound-processing system has components in common with said digital
electrochromic mirror system and said garage door opener.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. provisional
patent application Ser. No. 60/196,577, filed on Mar. 31, 2000, the
disclosure of which is hereby incorporated herein by reference in
its entirety.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to vehicle rearview mirror
systems and, more particularly, to digital electrochromic rearview
mirror systems.
[0003] Digital electrochromic mirror systems are described in
commonly assigned U.S. Pat. No. 6,089,721 entitled DIGITAL
ELECTROCHROMIC MIRROR SYSTEM and U.S. Pat. No. 6,056,410 entitled
DIGITAL ELECTROCHROMIC MIRROR SYSTEM, the disclosures of which are
hereby incorporated herein by reference. Such systems are capable
of controlling the reflectance level of an electrochromic element
from the output of a microcomputer.
[0004] Various forms of vehicle communication systems have been
developed including wired networks, or busses, operating one of
several known protocols. These include a LIN (Local Interconnect
Network), a LAN (Local Area Network), a CAN (Car or Controlled Area
Network), and the like. An advantage of such vehicle networks is
that the wire harness to the mirror can be minimized to as few as
three wires or so, yet provide a variety of functions. Wireless
communication networks utilizing radio frequency and/or infrared
communication for vehicles have also been proposed, such as those
utilizing the BLUETOOTH protocol. Such wireless communication and
the BLUETOOTH protocol are described in more detail in commonly
assigned U.S. patent application Ser. No. 09/793,002, filed Feb.
26, 2001, entitled VIDEO MIRROR SYSTEMS INCORPORATING AN ACCESSORY
MODULE, the disclosure of which is hereby incorporated herein by
reference.
[0005] Trainable garage door openers, such as a universal garage
door opener available from Johnson Controls/Prince Corporation,
Holland, Mich. under the trade name HOMELINK.TM., include a
transmitter for a universal home access system, which replaces the
switch in a household garage door opener that opens/closes the
garage door. A garage door opener communicating with a smart switch
that is programmable to a household specific code that is of the
rolling code type, such as is available from TRW Automotive,
Farmington Hills, Mich. under the trade name KWIKLINK.TM., is known
to be mounted within vehicles. As described in commonly assigned
U.S. Pat. No. 6,172,613 B1, the disclosure of which is hereby
incorporated herein by reference, the universal garage door opener
HOMELINK.TM. unit or the universal home access KWIKLINK.TM. unit
may be mounted at, within, or on an interior rearview mirror
assembly. The KWIKLINK.TM. system is a low-current device that can,
optionally, be operated off of a battery source, such as a
long-life lithium battery. It is also compact and lightweight as
executed on a single-or double-sided printed circuit board.
SUMMARY OF THE INVENTION
[0006] The present invention provides a new and unique combination
of a digital electrochromic mirror system, a vehicle accessory and
a vehicle network, and, more particularly, a combination of a
digital electrochromic mirror system, a garage door opener and a
vehicle network. According to an aspect of the invention, a
vehicular rearview mirror system includes a digital electrochromic
mirror system having a digital drive circuit and an electrochromic
reflective element. The reflective element assumes a partial
reflectance level in response to a drive signal. The drive circuit
provides a drive signal to the reflectance element. The mirror
system further includes a garage door opener including a
transmitter and a logic circuit. The logic circuit supplies signals
to the transmitter for transmitting garage door opening signals.
The mirror system further includes a microcontroller which defines,
at least in part, the digital drive circuit and the logic circuit.
In this manner, the digital electrochromic mirror system has
components in common with the garage door opener. According to this
aspect of the invention, the microcontroller communicates over a
vehicle network with at least a module performing at least one
other vehicle function. The vehicle network may have at least wired
network connections and may further have wireless connections. The
vehicle network may have a protocol selected from the group
consisting of a LIN, a CAN, or a LAN.
[0007] According to this aspect of the invention, the digital drive
circuit and the logic circuit may be mounted on a common circuit
board. Power to the digital drive circuit and logic circuit may be
supplied from a battery, preferably a rechargeable battery, that is
separate from the vehicle ignition. The battery may be charged from
a solar power system.
[0008] According to another aspect of the invention, a vehicle
rearview mirror system includes an interior rearview mirror system
made up of an electrochromic reflective element, a housing for the
electrochromic reflective element and a circuit board in the
housing. The electrochromic reflective element assumes a partial
reflectance level in response to a drive signal. A digital
electrochromic drive circuit is provided on the circuit board and
supplies a drive signal to the reflective element. The mirror
system further includes a garage door opener. The garage door
opener includes a transmitter and a logic circuit, at least one of
which (and preferably, both) is on the circuit board, and share
components with, the electrochromic drive circuit. The logic
circuit supplies signals to the transmitter for transmitting garage
door opening signals. The garage door opener may, optionally and
preferably, also serve as a receiver or a transceiver for a tire
pressure status monitoring/display system, such as disclosed in
commonly assigned U.S. patent application Ser. No. 09/513,941,
filed Feb. 28, 2000, entitled TIRE INFLATION ASSISTANCE MONITORING
SYSTEM, and U.S. patent application Ser. No. 09/710,016, filed Nov.
10, 2000, entitled TIRE INFLATION ASSISTANCE MONITORING SYSTEM, the
disclosures of which are hereby incorporated herein by reference,
and thus have a dual tire pressure monitoring/display and garage
door opener function. The mirror system further includes a
microcontroller which defines, at least in part, the digital drive
circuit and the logic circuit. The digital electrochromic mirror
system has components in common with the garage door opener. The
microcontroller communicates over a vehicle network with at least
one module performing at least one other vehicle function.
[0009] These and other objects, advantages and features of this
invention will become apparent upon review of the following
specification in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a top plan view of a vehicle having a vehicular
rearview mirror system, according to the invention;
[0011] FIG. 2 is an electronic block diagram of a digital
electrochromic mirror system, according to the invention; and
[0012] FIG. 3 is an electronic block diagram of a vehicular
rearview mirror system, according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] Referring now specifically to the drawings, and the
illustrative embodiments depicted therein, a vehicular rearview
mirror system 10 is illustrated with a vehicle 11 and includes an
interior rearview mirror assembly 16 and one or more exterior
rearview mirror assemblies, such as driver side exterior rearview
mirror assembly 12 and/or passenger side exterior rearview mirror
assembly 14 (FIG. 1). Interior rearview mirror assembly 16 includes
a digital electrochromic mirror system 18 which is preferably
supplied according to the principles disclosed in commonly assigned
U.S. Pat. Nos. 6,089,721 and 6,056,410, the disclosures of which
are hereby incorporated herein by reference. Although the
particulars of the invention are illustrated with an interior
rearview mirror assembly 16, it should be understood that the
principles of the invention could be equally applied to either or
both exterior rearview mirror assemblies 12, 14.
[0014] Digital electrochromic mirror system 18 includes a
microcontroller 20 and an electrochromic mirror reflective element
22. As is disclosed in the '721 and '410 patents, microcontroller
20 receives inputs from light sensors 24 (preferably
phototransistors or photodiodes) and supplies digital outputs 26a,
26b which control solid-state switches 28a, 28b in order to provide
a drive signal at 30 thereby establishing a partial reflectance
level of electrochromic reflective element 22. Microcontroller 20
includes a microprocessor.
[0015] Digital electrochromic mirror system 18 further includes a
bus interface 32 which interfaces with a vehicle network, or bus,
34. Items on network 34 can be connected by wired or wireless
connection. Wired connection may include wire, cables, fiber-optic
cables, and the like. Wireless connection can be by infrared (IR)
or radio-frequency (RF) communication, and, preferably, may be a
short-range RF interconnection using the BLUETOOTH protocol.
Vehicle network, or bus, 34 may utilize various buss protocols
including a Local Internet Network (LIN), a Local Area Network
(LAN), a Car (a/k/a Controlled) Area Network (CAN), or other
vehicle network protocol. The BLUETOOTH protocol is a low-cost,
low-power radio-based cable replacement or wireless link based on
short-range radio-based technology. BLUETOOTH enables creation of a
short-range (typically 30 feet or so, although longer and shorter
ranges are possible), wireless personal area network via small
radio transmitters built into various devices. For example,
transmission can be on a 2.45 gigahertz band, moving data at about
721 kilobits per second, or faster. In the illustrated embodiment,
network 34 is a multi-drop bus which requires three or fewer wires
for communication between a plurality of other vehicle functions
36, as illustrated in FIG. 3. In situations where timing and power
consumption system constraints may cause network 34 wakeup time to
be too slow for an automobile maker system response requirement,
suitable adjustments may be made in the architecture of network 34.
The network may be configured as disclosed in commonly assigned
U.S. patent application Ser. No. 09/341,450 filed Jul. 8, 1999, by
Drummond et al. for a VEHICLE REARVIEW MIRROR AND A VEHICLE CONTROL
SYSTEM INCORPORATING SUCH MIRROR, the disclosure of which is hereby
incorporated herein by reference.
[0016] Other vehicle functions 36 include, by way of example, a
seatbelt warning status 38, which status may be displayed on a
mirror-based display 40. Preferably, mirror-based display 40 may be
located on, at or adjacent interior rearview mirror assembly 16.
Mirror-based display 40 may be of various forms including that
disclosed in commonly assigned U.S. patent application Ser. No.
09/799,414, filed on Mar. 5, 2001, by McCarthy et al., entitled
COMPLETE MIRROR-BASED GLOBAL-POSITIONING SYSTEM (GPS) NAVIGATION
SOLUTION, the disclosure of which is hereby incorporated herein by
reference. Additionally, display 40 may display magnetic vehicle
heading information from a magnetic sensor 42, the information
being supplied over network 34. Additionally, reverse gear status
from a reverse gear sensor 44 may be supplied over network 34 to
cause digital electrochromic mirror 18 to assume a high reflectance
level when vehicle 11 is placed in reverse gear. Rearview mirror
system 10 may additionally receive engine information 46 and/or
door opener information at 48 over network 34 and activate general
lighting 50 located in, at or on interior rearview mirror assembly
16, such as when a door of vehicle 11 is opened. Status from an
alarm assembly 52 may also be conveyed over network 34 and
displayed by display 40.
[0017] Dim ratios, or partial reflectance levels developed from
light sensors 24, can be transmitted over network 34 for use to
drive exterior mirrors 12, 14. Optionally, a dim ratio or partial
reflectance level chosen for a driver-side exterior mirror may be
different from (and typically greater than) a dim ratio or partial
reflectance level chosen for a passenger-side exterior mirror, and
both may be different from a dim ratio or partial reflectance level
chosen for a interior electrochromic mirror. Ambient light
information, sensed by an ambient light sensor 57, can also be
transmitted over network 34 for use in dimming of instrument panel
54 or automatic headlight functions 56. Alternatively, ambient
light information can be developed by interior rearview mirror
assembly 16 as disclosed in commonly assigned U.S. Pat. No.
5,715,093, the disclosure of which is hereby incorporated herein by
reference.
[0018] The interior rearview mirror assembly includes
microcontroller 20 and a printed circuit board 61, that are common
to both the digital electrochromic mirror system 18 and garage door
opener function 66. Sharing of components and circuit board space
can facilitate a reduction of susceptibility to RF/EMI interference
and reduce cost and avoid duplication of both the network interface
hardware 32, communication software and some processing power. The
interior rearview mirror assembly may also include a video display
system, such as disclosed in commonly assigned U.S. patent
application Ser. No. 09/793,002, filed Feb. 26, 2001, entitled
VIDEO MIRROR SYSTEM INCORPORATING AN ACCESSORY MODULE, the
disclosure of which is hereby incorporated herein by reference.
Components may be shared between the video display system, the
digital electrochromic mirror system and/or the garage door opener.
Additionally, microcontroller 20 may control a forward-facing
camera system and headlight control which may also share components
with the digital electrochromic mirror system and/or the garage
door opener. Such forward-facing camera system and headlight
control may be of the type disclosed in commonly assigned U.S. Pat.
No. 5,796,094 entitled VEHICLE HEADLIGHT CONTROL USING IMAGING
SENSOR, the disclosure of which is hereby incorporated herein by
reference. An imaging sensor based rain sensor of the type
disclosed in commonly assigned U.S. patent application Ser. No.
09/530,306, filed Apr. 27, 2000, entitled RAIN SENSOR WITH FOG
DISCRIMINATION, 5 may also be incorporated in circuit board 61 and
share components with the digital electrochromic mirror system
and/or the garage door opener.
[0019] With microcomputer 20 driving digital electrochromic mirror
system 18, and with vehicle status information available over
network 34, it is possible to have a circuit assembly 61 in or at
interior rearview mirror assembly 16 that is powered by a battery
62 that is 10 separate from the vehicle ignition storage battery.
As an example, battery 62 may be of a long-life lithium type
battery. Moreover, because of its relatively small size, battery 62
may be recharged by a separate dedicated solar-powered rechargeable
battery source 64 of the type described in commonly assigned patent
application Ser. No. 09/793,002, filed Feb. 26, 2001, entitled
VIDEO MIRROR SYSTEMS INCORPORATING AN ACCESSORY MODULE, the
disclosure of which is hereby incorporated herein by reference. By
powering mirror system 10 by a separate-dedicated solar-powered
rechargeable battery source, mirror system 10 can consume power
from its dedicated/local battery source, and any power used up
during nighttime hours can be replenished by day via solar
cell/panel that is a part of battery charger 64 and is connected to
the dedicated battery 62 so as to recharge/charge during daytime
hours. Furthermore, microcomputer 20 can be put into various
power-saving modes thereby enabling electronic assembly 61 to be
used for control of a garage door opener 66, such as a HOMELINK.TM.
unit or the universal home access KWIKLINK.TM. unit.
[0020] Also, a mirror-mounted microphone/digital sound-processing
system 68, as disclosed in commonly assigned patent application
Ser. No. 09/466,010, filed by DeLine et al., on Dec. 17, 1999, for
an INTERIOR REARVIEW MIRROR SOUND-PROCESSING SYSTEM, the disclosure
of which is hereby incorporated herein by reference, may be also
powered by battery 62. Preferably, sound-processing system 68 is
incorporated in circuit assembly 61 and, most preferably, shows
microcontroller 20 with garage door opener 66 and digital
electrochromic mirror 18. Communication button press information 58
can be transmitted over network 34 for various uses by other
electronic control units, such as activation of a rescue system 60,
such as General Motors' ONSTAR.TM. system, a Ford Motor Company's
RESCU.TM. system, or the like. Use of digital signal-processing and
a single mirror-mounted microphone (such as is described in U.S.
patent application Ser. No. 09/396,179, filed Sep. 14, 1999,
entitled INDICATOR FOR VEHICLE ACCESSORY, the disclosure of which
is incorporated by reference herein) is particularly advantageous
for economical achievement of clear and error-free transmission
from the vehicle, while operating along a highway, to a remote
receiver, particularly in speech-recognition mode. This use of
network 34 facilitates location of button 58 in interior mirror
assembly 16.
[0021] Microcomputer 20 may receive memory information 70 over
network 34 and actuate an actuator 72 to position reflective
element 24. Principles, disclosed in commonly assigned U.S. Pat.
No. 5,796,176 entitled MEMORY MIRROR SYSTEM FOR VEHICLES, the
disclosure of which is hereby incorporated herein by reference, may
be utilized for communicating such memory information over network
34.
[0022] Microcomputer 20 may also use network 34 to measure values
of light sensed by light sensors 24, supply drive signals to the
electrochromic reflective element, and the like, on the network 34.
Partial reflectance levels may be communicated to exterior rearview
mirror assemblies 12, 24 over network 34. In this manner, if the
interior digital electrochromic mirror system 18 develops a fault,
incorrect information will not be transmitted to exterior rearview
mirror systems. This also allows exterior reflective elements to
have different peak voltages and provides more precise control over
each of the mirror assemblies 12, 14, 16.
[0023] Other functions may be controlled over network 34 such as
remote keyless entry 74 and global positioning system
information/navigational system as described in commonly assigned
co-pending application Ser. No. 09/799,414, filed on Mar. 5, 2001,
by McCarthy et al., entitled COMPLETE MIRROR-BASED
GLOBAL-POSITIONING SYSTEM (GPS) NAVIGATION SOLUTION, the disclosure
of which is hereby incorporated herein by reference.
[0024] In addition to placement at, on or in exterior rearview
mirror assembly 18, circuit board 61 may be positioned at a
location (and preferably in a housing) separate from interior
mirror assemblies, such as disclosed in commonly assigned U.S. Pat.
No. 6,099,131 entitled ELECTRO-OPTIC MIRROR SYSTEM, the disclosure
of which is hereby incorporated herein by reference.
[0025] Also, the concepts of the present invention provides a new
and unique combination of a digital electrochromic mirror system, a
vehicle accessory and a vehicle network when the vehicle accessory
comprises a tire pressure monitoring/display system.
[0026] Changes and modifications in the specifically described
embodiments can be carried out without departing from the
principles of the invention which is intended to be limited only by
the scope of the appended claims, as interpreted according to the
principles of patent law including the doctrine of equivalents.
* * * * *