US 6,081,755 A · Vehicle control device

Abstract

A vehicle control device has an PROM with a first and second memory area. The contents of the PROM are updated by erasing locations for a vehicle control program, writing part of the vehicle control program into the PROM, checking for abnormalities in the writing process, and then writing the remaining part of the vehicle control program into the PROM only when the result of writing the part first is determined not to have been abnormal. This determination may be based on a checksum, of the program codes that were expected to have been written into the first memory area as the first part of the vehicle control program, compared with the checksum of the program codes actually written. In the event of an abnormality, only the part of the vehicle control program first written is in the PROM, and the area in which the remaining part of the vehicle control program would have been written remains erased. The remaining part of the vehicle control program is a part of the program necessary for proper functioning, such as the reset vector. If the reset vector of the vehicle control program is used as the remaining part, and the remaining part is not written due to the detection of an abnormality, then any attempt to execute the abnormally updated control program will result in performance that is manifestly abnormal and easy to detect in subsequent production steps.

Claims14

Dependent claims

An apparatus for updating a memory with a vehicle control program, wherein said memory has memory locations for storing said vehicle control program, said apparatus comprising:

a vehicle control program adapted to perform an arithmetic process, on the basis of a vehicle drive state, to output a vehicle control amount;
said vehicle control program comprising a part of said vehicle control program to be written first, and a remaining part of said vehicle control program, wherein said part to be written first defines first write data, and said remaining part defines second write data;
means for erasing said memory locations;
first writing means for writing, after said means for erasing erases said memory locations, in one or more of said memory locations, said first write data, said one or more of said memory locations defining a first set of said memory locations;
collating means for making a determination whether said writing of said first write data was abnormally performed;
and
second writing means for writing, only when said determination indicates said writing of said first write data was not abnormally performed, said second write data in a second set of said memory locations, one or more of said second memory locations being different from said first set of said memory locations;
wherein, when said determination indicates said writing of said first write data was abnormally performed, said second writing means does not write said second write data in said second set of said memory locations.

5 more elements

A method of storing a vehicle control program in a memory, wherein said memory has memory locations for storing said vehicle control program, said method comprising:

providing a vehicle control program adapted to perform an arithmetic process, on the basis of a vehicle drive state, to output a vehicle control amount;
determining, for said vehicle control program, a part of said vehicle control program to be written first, and a remaining part of said vehicle control program, wherein said part to be written first defines first write data, and said remaining part defines second write data;
erasing said memory locations;
then
writing, in one or more of said memory locations, said first write data, said one or more of said memory locations defining a first set of said memory locations;
then
making a determination whether said writing of said first write data was abnormally performed;
and
only when said determination indicates said writing of said first write data was not abnormally performed, writing said second write data in a second set of said memory locations, one or more of said second memory locations being different from said first set of said memory locations.

6 more elements

Dependencies are inferred from the claim text.

Vehicle control device

Life of this patent

Vehicle control device

Life of this patent

Abstract

Claims14