In-vehicle unit communication protocol

1. A vehicle control system communication method, comprising:

receiving, at an in-vehicle unit (IVU), a command message from a hand-held unit (HHU), wherein the command message includes first to third command frames; and

sending, from the IVU, a response message to the HHU, wherein the response message includes first and second response frames,

wherein the first response frame is sent in a time period between the reception of the first and second command frames and the second response frame is sent in a time period between the reception of the second and third command frames, and

wherein the first to third command frames each instruct a vehicle to perform a first function, and the first response frame includes a status of the vehicle related to the first function and an identification (id) of the IVU which is validated by the HHU prior to accepting data from the second response frame, and the second response frame includes current vehicle gauge data.

2. The method of claim 1 , wherein the time period between the reception of the first command frame and the reception of the second command frame is approximately 100 ms or approximately 150 ms.

3. The method of claim 1 , wherein the first response frame is sent approximately 50 ms or approximately 75 ms after the first command frame is received.

4. The method of claim 1 , wherein the time period between the reception of the second command frame and the reception of the third command frame is approximately 100 ms or approximately 150 ms.

5. The method of claim 1 , wherein the second response frame is sent approximately 50 ms or approximately 75 ms after the second command frame is received.

6. The method of claim 1 , wherein when the IVU receives the first command frame from the HHU a communication session begins and when the HHU receives a last response frame from the IVU the communication session ends.

7. The method of claim 6 , wherein when the communication session ends, the HHU does not receive another response message from the IVU until another communication session begins.

8. The method of claim 1 , wherein the response message is sent a predetermined number of times.

9. The method of claim 1 , further comprising:

validating, at the IVU, a learn command message received from the HHU or a valid setup request from an HHU already learned, by sending, from the IVU, a series of calibration frames to the HHU, wherein each calibration frame comprises the IVU id, a first calibration byte, a second calibration byte and a checksum.

10. The method of claim 9 , wherein the series of calibration frames is sent approximately 100 ms or approximately 150 ms apart.

11. The method of claim 1 , wherein the command message and the response message are wirelessly transmitted using radio frequency (RF), ZigBee, Near Field Communication (NFC), Bluetooth, ultra-wide band or infrared techniques.

12. The method of claim 1 , further comprising obtaining the IVU id, wherein the obtaining comprises:

concatenating two copies of an id of the HHU to create a 64-bit number;

transforming the 64-bit number into a 64-bit result by decryption; and

taking a middle 16-bits of the 64-bit result as the IVU id.

13. The method of claim 1 , wherein the response message further includes a third response frame sent after the third command frame is received by the IVU, the third response frame including a checksum and vehicle gauge data different from the vehicle gauge data of the second response frame, the first response frame further including a checksum,

wherein the data of the first response frame is accepted at the HHU in response to validation of the IVU id and the checksum of the first response frame and the data of the second and third response frames is accepted at the HHU in response to validation of the checksum of the third response frame.

14. A vehicle control system, comprising:

a hand held unit (HHU) for transmitting a first to third command frames, wherein the first to third command frames each direct a vehicle to perform a first function; and

an in-vehicle unit (IVU) for receiving the first to third command frames and sending first and second response frames to the HHU, wherein the first response frame is sent in a time period between the reception of the first and second command frames and includes a status of the vehicle related to the first function and an identification (id) of the IVU which is validated by the HHU prior to accepting data from the second response frame, and the second response frame is sent in a time period between the reception of the second and third command frames and includes current vehicle gauge data.

15. The system of claim 14 , further comprising:

a vehicle control module for receiving a command from the IVU associated with the first to third command frames received from the HHU and for instructing vehicle components to execute functions in accordance with the command received from the IVU.

16. The system of claim 15 , wherein the vehicle control module communicates with the vehicle components via a vehicle data bus.

17. The system of claim 16 , wherein the vehicle data bus is a controller area network (CAN) data bus.

18. The system of claim 15 , wherein a vehicle component executes a function in accordance with the command received from the IVU in response to the instruction of the vehicle control module.

19. The system of claim 14 , wherein the IVU instructs the vehicle components to execute functions associated with the first to third command frames received from the HHU.

20. The system of claim 19 , wherein the IVU communicates with the vehicle components via a vehicle data bus.

21. The system of claim 20 , wherein the vehicle data bus is a CAN data bus.

22. The system of claim 19 , wherein a vehicle component executes a function associated with the first to third command frames received from the HHU in response to a command received from the IVU.

23. The system of claim 14 , wherein when the IVU is hardwired to vehicle components, the IVU instructs the vehicle components to execute functions associated with the first to third command frames received from the HHU via the hardwired connection.

24. The system of claim 23 , wherein a vehicle component executes a function associated with the first to third command frames received from the HHU in response to a command received from the IVU via the hardwired connection.

25. The system of claim 14 , wherein the first to third command frames and the first and second response frames are wirelessly transmitted using radio frequency (RF), ZigBee, Near Field Communication (NFC), Bluetooth, ultra-wide band or infrared techniques.

26. A method for wirelessly communicating between a remote transceiver and a vehicle control system, comprising:

receiving, at a vehicle control unit, a command message from a remote transceiver, wherein the command message includes first to third command frames; and

sending, from the vehicle control unit, a response message to the remote transceiver, wherein the response message includes first and second response frames,

wherein the first response frame is interleaved between the first and second command frames and the second response frame is interleaved between the second and third command frames, and

wherein the first to third command frames each instruct a vehicle to perform a first function, and the first response frame includes a status of the vehicle related to the first function and an identification (id) of the vehicle control unit which is validated by the remote transceiver prior to accepting data from the second response frame, and the second response frame includes current vehicle gauge or diagnostic data.