CONTROL DEVICE FOR VEHICLE AND ERROR PROCESSING METHOD IN CONTROL DEVICE FOR VEHICLE

• US 20140047299A1
• Filed: 03/18/2013
• Published: 02/13/2014
• Est. Priority Date: 08/10/2012
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: IKEDA, Yoshinori
• Granted Patent: US 9,110,842 B2
• Time in Patent Office: Days
• US Class Current: 714/764
• CPC Class Codes: G06F 11/1048 using arrangements adapted for a specific error detection or correction feature
• CPC Class Codes: G06F 11/1417 Boot up procedures
• CPC Class Codes: G06F 11/30 Monitoring
• CPC Class Codes: G06F 12/02 Addressing or allocation; Relocation program address sequencing G06F9/00; arrangements for selecting an address in a digital store G11C8/00
• CPC Class Codes: G06F 12/16 Protection against loss of memory contents contains no material, see G06F11/00

Abstract

A control device for a vehicle including a nonvolatile memory which is electrically erasable and writable detects, on start-up, whether or not an error occurs in updated data read from the nonvolatile memory, and when an error has been detected, performs a reset after saving error information. When being restarted by the reset, the control device for a vehicle determines on the basis of the error information whether or not there is updated data in which an error has occurred, and when there is updated data in which an error has occurred, overwrites the updated data with a fixed value prior to the error detection. Accordingly, there can be suppressed a case in which the error detection is performed while the updated data with an abnormality is present causing the reset and the error detection to be repeated.

Claims

1. A control device for a vehicle comprising:

a nonvolatile memory which is electrically erasable and writable;

an error detection unit which detects, on start-up, whether or not an error occurs in updated data in the nonvolatile memory;

a reset unit which performs a reset when an error is detected by the error detection unit; and

a rewrite unit which rewrites, when the device is restarted by the reset, updated data in which the error has occurred with a predetermined value prior to error detection to be performed by the error detection unit.

2. The control device for a vehicle according to claim 1,

wherein the error detection unit saves an address of the updated data in which the error has been detected, and

the rewrite unit rewrites the updated data with the predetermined value on the basis of the address.

3. The control device for a vehicle according to claim 1, further comprising a write unit which writes identical updated data to a plurality of areas in the nonvolatile memory,

wherein the rewrite unit rewrites, when the device is restarted by the reset, the updated data in an area in which the error has occurred with updated data in another area in which the identical updated data is written.

4. The control device for a vehicle according to claim 1,

wherein the reset unit includes:

a program run signal output unit which discontinues output of a program run signal when the error is detected in the updated data; and

a reset signal output unit which outputs a reset signal when the output of the program run signal from the program run signal output unit is discontinued.

5. The control device for a vehicle according to claim 1, wherein the reset unit, the error detection unit, and the rewrite unit includes a computing unit which resets itself when detecting an error in the updated data.

6. The control device for a vehicle according to claim 1, further comprising:

a first circuit which receives power supply from an external power source via a power switch;

a second circuit which receives power supply from the external power source by bypassing the power switch;

a relay provided to the second circuit; and

a power source control unit which receives power supply from the second circuit when the power switch is turned off while updated data is being written in the nonvolatile memory, and which turns off the relay when the writing is completed to perform self shut-off.

7. The control device for a vehicle according to claim 1, wherein the reset unit performs a reset when an error which cannot be corrected has occurred in the updated data.

8. The control device for a vehicle according to claim 1, wherein the rewrite unit rewrites an error correction code written in the nonvolatile memory with a predetermined value along with the updated data being rewritten with the predetermined value.

9. The control device for a vehicle according to claim 1, wherein the rewrite unit overwrites all areas of the nonvolatile memory in which the updated data is stored with a predetermined value.

10. The control device for a vehicle according to claim 1, wherein the rewrite unit rewrites the updated data with a value different for each address.

11. The control device for a vehicle according to claim 1, wherein the rewrite unit rewrites the updated data with a fixed value.

12. The control device for a vehicle according to claim 1, wherein the error detection unit detects whether or not an error occurs by collating updated data stored in the nonvolatile memory with an error correction code of the updated data.

13. The control device for a vehicle according to claim 1, wherein the reset unit performs a reset after saving error information when an error is detected.

14. The control device for a vehicle according to claim 1, wherein the updated data is a type of data which is updated by learning control.

15. A control device for a vehicle comprising:

a nonvolatile memory which is electrically erasable and writable;

error detection means which detects, on start-up, whether or not an error occurs in updated data in the nonvolatile memory;

reset means which performs a reset when an error is detected by the error detection means; and

rewrite means which rewrites, when the device is restarted by the reset, updated data in which the error has occurred with a predetermined value prior to error detection to be performed by the error detection means.

16. An error processing method performed in a control device for a vehicle including a nonvolatile memory which is electrically erasable and writable, the method comprising steps of:

determining on start-up whether or not there is a history of detecting an error in updated data in the nonvolatile memory;

detecting, when there is no history of detecting an error, whether or not an error occurs in the updated data in the nonvolatile memory;

rewriting, when there is a history of detecting an error, the updated data in which the error has occurred with a predetermined value and subsequently detecting whether or not an error occurs in the updated data in the nonvolatile memory; and

resetting the control device for a vehicle when an error is detected in the updated data.

17. The error processing method performed in a control device for a vehicle according to claim 16,

wherein the step of resetting the control device for a vehicle includes steps of:

saving an address of the updated data from which an error has been detected; and

resetting the control device for a vehicle after saving the address.

18. The error processing method performed in a control device for a vehicle according to claim 16, further comprising a step of writing identical updated data to a plurality of areas in the nonvolatile memory,

wherein the step of rewriting the updated data in which the error has occurred with the predetermined value includes a step of:

rewriting the updated data in which the error has occurred with updated data in another area in which the identical updated data is written.

19. The error processing method performed in a control device for a vehicle according to claim 16,

wherein the step of detecting whether or not an error occurs in the updated data includes a step of:

detecting whether or not an error occurs by collating updated data stored in the nonvolatile memory with an error correction code of the updated data.

20. The error processing method performed in a control device for a vehicle according to claim 19,

wherein the step of rewriting the updated data in which the error has occurred with the predetermined value includes a step of:

rewriting an error correction code written in the nonvolatile memory with a predetermined value along with the updated data being rewritten with the predetermined value.