System and method for memory reset of a vehicle controller

• US 5,884,211 A
• Filed: 01/23/1997
• Issued: 03/16/1999
• Est. Priority Date: 01/23/1997
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Schmitt, David Harold, Grant, Kathleen Arlow, Melville, Thomas Robert, Pauli, Allen Joseph
• Primary Examiner(s): Nelli, Raymond A.
• Application Number:
  US08/786,941
• Time in Patent Office: 782 Days
• Field of Search: 701/115, 364/431.12, 364/569, 315/77
• US Class Current: 701/115
• CPC Class Codes: G11C 16/22 Safety or protection circuits preventing unauthorised or accidental access to memory cells
• CPC Class Codes: G11C 7/20 Memory cell initialisation circuits, e.g. when powering up or down, memory clear, latent image memory
• CPC Class Codes: G11C 7/24 Memory cell safety or protection circuits, e.g. arrangements for preventing inadvertent reading or writing; Status cells; Test cells

Abstract

A system and method for resetting a portion of memory in a vehicle controller include repeatedly comparing data stored in at least one validation address with corresponding data stored in a non-volatile data storage device, transferring data representing nominal control parameter values from the non-volatile storage device to the portion of memory in response to a discrepancy between the data stored in the validation address and the corresponding data stored in the non-volatile data storage device, and modifying data stored in at least one validation address based on a request received via a communication port to generate discrepancy. A memory reset function is provided while limiting access by service technicians to modify values stored in memory and eliminating the need to disconnect the vehicle battery to remove power from the system. As such, other vehicle accessories are not affected by the reset function.

Claims

1. A method for resetting keep-alive memory in a vehicle controller having a processor in communication with the keep-alive memory and a non-volatile memory, the controller also including a communication port controlled by the processor for transferring information, the method comprising:

receiving a request to reset at least a portion of the keep-alive memory;

modifying data stored within the portion of the keep-alive memory to induce a fault condition which causes a reset of the keep-alive memory.

2. The method of claim 1 further comprising generating a status message in response to the request to reset at least a portion of the keep-alive memory.

3. The method of claim 1 wherein the step of modifying comprises transferring data from the non-volatile memory to the portion of the keep-alive memory to reset the keep-alive memory.

4. The method of claim 1 wherein the step of modifying comprises modifying only one address within the portion of keep-alive memory to induce the fault condition.

5. The method of claim 1 wherein the step of modifying comprises:

comparing data from at least one address of the keep-alive memory with data from the non-volatile memory; and

transferring data from the non-volatile memory to the portion of keep alive memory to reset the portion of keep alive memory when the step of comparing indicates disparity between the data compared.

6. A method for resetting a portion of memory having stored adaptive engine control parameter values and at least one validation address in an engine controller which includes a processor in communication with the memory and with a non-volatile data storage device having stored nominal engine control parameter values, the engine controller also including a communication port controlled by the processor for transferring data to and from the engine controller to effect control of an engine, the method comprising:

repeatedly comparing data stored in the at least one validation address with corresponding data of the non-volatile data storage device;

transferring data representing the nominal engine control parameters from the non-volatile storage device to the portion of memory in response to a discrepancy between the data stored in the at least one validation address and the corresponding data stored in the non-volatile data storage device; and

modifying data stored in at least one of the at least one validation address based on a request received via the communication port to generate the discrepancy so as to reset the portion of memory.

7. The method of claim 6 further comprising:

determining whether the engine is stopped;

and

performing the step of modifying only after the step of determining indicates the engine is stopped.

8. The method of claim 6 wherein the step of modifying is performed only after entry of a predetermined password.

9. The method of claim 6 wherein the step of transferring comprises transferring the corresponding data from the non-volatile data storage device to the at least one validation address of the portion of memory.

10. A system for resetting a portion of memory of a control unit for a motor vehicle having stored modifiable parameter values and at least one validation address, the system comprising:

a non-volatile data storage device having stored nominal parameter values; and

control logic in communication with the non-volatile data storage device and the memory of the control unit;

wherein the control logic repeatedly compares data stored at the at least one validation address with corresponding data of the non-volatile data storage device, transfers data representing the nominal parameter values from the non-volatile data storage device to the portion of memory in response to a discrepancy between the data stored in the at least one validation address and the corresponding data stored in the non-volatile data storage device, and modifies data stored in at least one of the at least one validation address in response to a reset request to generate the discrepancy so as to reset the portion of memory.

11. The system of claim 10 further comprising a service tool connectable to the control unit for generating the reset request in response to a request from a user.

12. A computer readable storage medium having stored therein instructions executable by a computer to reset keep-alive memory in a vehicle controller, the computer readable storage medium comprising:

instructions for receiving a request to reset at least a portion of the keep-alive memory;

instructions for modifying data stored within the portion of the keep-alive memory to induce a fault condition which causes a reset of the keep-alive memory.

13. The computer readable storage medium of claim 12 further comprising instructions for generating a status message in response to the request to reset at least a portion of the keep-alive memory.

14. The computer readable storage medium of claim 12 wherein the instructions for modifying comprise instructions for transferring data from the non-volatile memory to the portion of the keep-alive memory to reset the keep-alive memory.

15. The computer readable storage medium of claim 12 wherein the instructions for modifying comprise instructions for modifying only one address within the portion of keep-alive memory to induce the fault condition.

16. The computer readable storage medium of claim 12 wherein the instructions for modifying comprise:

instructions for comparing data from at least one address of the keep-alive memory with data from the non-volatile memory; and

instructions for transferring data from the non-volatile memory to the portion of keep alive memory to reset the portion of keep alive memory when the step of comparing indicates disparity between the data compared.