Digital electrochromic circuit with a vehicle network

1. A vehicular rearview mirror system suitable for use in a vehicle, said vehicular rearview mirror system comprising:

an interior rearview mirror assembly comprising an interior electrochromic reflective element, said interior electrochromic reflective element assuming an interior mirror partial reflectance level in response to an interior mirror electrochromic reflective element drive signal;

a housing for said interior electrochromic reflective element;

said interior rearview mirror assembly comprising digital circuitry, said digital circuitry supplying said interior mirror electrochromic reflective element drive signal to said interior electrochromic reflective element;

said digital circuitry comprising a microcontroller;

said microcontroller controlling over a vehicle network at least one other vehicle function;

wherein one of said at least one other vehicle function comprises an exterior mirror assembly that includes an exterior electrochromic reflective element that assumes an exterior mirror partial reflectance level in response to an exterior mirror electrochromic reflective element drive signal;

wherein said microcontroller controls said exterior mirror partial reflectance level of said exterior electrochromic reflective element over said vehicle network; and

wherein said interior rearview mirror assembly includes at least one of a garage door opener and a forward-facing camera.

2. The vehicular rearview mirror system of claim 1 , wherein said vehicle network comprises at least one wired network connection.

3. The vehicular rearview mirror system of claim 2 , wherein said vehicle network comprises a protocol selected from the group consisting of a LIN, a CAN and a LAN.

4. The vehicular rearview mirror system of claim 3 , wherein said vehicle network comprises at least one of a wire, a cable and a fiber-optic connection.

5. The vehicular rearview mirror system of claim 1 , wherein said vehicle network at least partially comprises a wireless network.

6. The vehicular rearview mirror system of claim 5 , wherein said wireless network comprises a short-range wireless connection.

7. The vehicular rearview mirror system of claim 6 , wherein said wireless network comprises a BLUETOOTH protocol.

8. The vehicular rearview mirror system of claim 5 , wherein said wireless network comprises at least one of an infrared and a radio-frequency connection.

9. The vehicular rearview mirror system of claim 1 , wherein said interior mirror partial reflectance level of said interior electrochromic reflective element assumed in response to said interior mirror electrochromic reflective element drive signal differs from said exterior mirror partial reflectance level of said exterior electrochromic reflective element assumed in response to said exterior mirror electrochromic reflective element drive signal.

10. The vehicular rearview mirror system of claim 1 , wherein said at least one other vehicle function includes a function associated with at least one of an instrument panel and a headlight control circuit.

11. The vehicular rearview mirror system of claim 1 , wherein said at least one other vehicle function comprises a reverse gear detection function and wherein said digital circuitry responds to reverse gear information sent over said vehicle network to establish a high reflectance level of said interior electrochromic reflective element.

12. The vehicular rearview mirror system of claim 1 , wherein said microcontroller comprises a microprocessor.

13. The vehicular rearview mirror system of claim 1 , wherein said vehicle network comprises at least a wired connection comprising no more than three wires.

14. The vehicular rearview mirror system of claim 1 , wherein said at least one other vehicle function comprises at least one of (a) a remote keyless entry function, (b) a navigational system function, (c) a global-positioning system function, (d) a telematics function and (e) a display function.

15. The vehicular rearview mirror system of claim 1 , wherein said interior rearview mirror assembly includes a user control, actuation of which is transmitted over said vehicle network.

16. The vehicular rearview mirror system of claim 15 , wherein said user control comprises a user-operable button.

17. The vehicular rearview mirror system of claim 1 , wherein said interior rearview mirror assembly comprises a forward-facing camera and wherein said forward-facing camera is at least partially controlled by said microcontroller.

18. A vehicular rearview mirror system suitable for use in a vehicle, said vehicular rearview mirror system comprising:

an interior rearview mirror assembly comprising an interior electrochromic reflective element, said interior electrochromic reflective element assuming an interior mirror partial reflectance level in response to an interior mirror electrochromic reflective element drive signal;

a housing for said interior electrochromic reflective element;

said interior rearview mirror assembly comprising digital circuitry, said digital circuitry supplying said interior mirror electrochromic reflective element drive signal to said interior electrochromic reflective element;

said digital circuitry comprising a microprocessor;

said microprocessor controlling over a vehicle network at least one other vehicle function;

wherein one of said at least one other vehicle function comprises a driver-side exterior mirror assembly that includes a driver-side exterior electrochromic reflective element that assumes a driver-side mirror partial reflectance level in response to an exterior mirror electrochromic reflective element drive signal;

wherein said microprocessor controls said driver-side mirror partial reflectance level of said driver-side exterior electrochromic reflective element over said vehicle network; and

wherein said interior rearview mirror assembly comprises a forward-facing camera and wherein said forward-facing camera is at least partially controlled by said microprocessor.

19. The vehicular rearview mirror system of claim 18 , wherein said vehicle network comprises at least one wired network connection, and wherein said vehicle network comprises a protocol selected from the group consisting of a LIN, a CAN and a LAN.

20. The vehicular rearview mirror system of claim 18 , wherein said interior mirror partial reflectance level of said interior electrochromic reflective element assumed in response to said interior mirror electrochromic reflective element drive signal differs from said driver-side mirror partial reflectance level of said driver-side exterior electrochromic reflective element assumed in response to said exterior mirror electrochromic reflective element drive signal.

21. A vehicular rearview mirror system suitable for use in a vehicle, said vehicular rearview mirror system comprising:

an interior rearview mirror assembly comprising an interior electrochromic reflective element, said interior electrochromic reflective element assuming an interior mirror partial reflectance level in response to an interior mirror electrochromic reflective element drive signal;

a housing for said interior electrochromic reflective element;

said interior rearview mirror assembly comprising digital circuitry, said digital circuitry supplying said interior mirror electrochromic reflective element drive signal to said interior electrochromic reflective element;

said digital circuitry comprising a microprocessor;

said microprocessor controlling over a vehicle network at least one other vehicle function;

wherein one of said at least one other vehicle function comprises a driver-side exterior mirror assembly that includes a driver-side exterior electrochromic reflective element that assumes a driver-side mirror partial reflectance level in response to an exterior mirror electrochromic reflective element drive signal;

wherein said microprocessor controls said driver-side mirror partial reflectance level of said driver-side exterior electrochromic reflective element over said vehicle network; and

wherein said interior rearview mirror assembly comprises a garage door opener and wherein said garage door opener is at least partially controlled by said microprocessor.

22. The vehicular rearview mirror system of claim 21 , wherein said vehicle network comprises at least one wired network connection, and wherein said vehicle network comprises a protocol selected from the group consisting of a LIN, a CAN and a LAN.

23. The vehicular rearview mirror system of claim 21 , wherein said interior mirror partial reflectance level of said interior electrochromic reflective element assumed in response to said interior mirror electrochromic reflective element drive signal differs from said driver-side mirror partial reflectance level of said driver-side exterior electrochromic reflective element assumed in response to said exterior mirror electrochromic reflective element drive signal.