Abstract: A memory rewriting system for a vehicle controller is provided. The system comprises a vehicle controller and an external rewriting device. A vehicle controller comprises a rewritable memory storing first security data. The first security data is used to determine whether rewriting to the rewritable memory is permitted. The rewriting device transfers new security data to the vehicle controller. The vehicle controller deletes the first security data and writes the new security data into the rewritable memory. Rewriting the new security data is performed by a program stored in a non-rewritable memory. Thus, the security data that is used to determine whether rewriting to the rewitable memory is permitted is rewritten with the new security data. Therefore, if the existing security data stored in the vehicle controller is invalidated, the security feature of the vehicle can be recovered. The vehicle may includes an anti-theft system.

Abstract: The rewriting device for rewriting data stored in a memory of a vehicle controller with new data is provided. The rewriting device is capable of communicating with the vehicle controller. When deleting or writing operation on the memory is not being performed, the rewriting device determines that communication between the rewriting device and the vehicle controller is offline if no response from the vehicle controller within a first determination time. When deleting operation or writing operation on the memory is being performed, the determination of offline is prohibited until a second determination time has elapsed. The second determination time is greater than the first determination time. It is preferable that the second determination time for deleting operation is the time necessary to delete the data stored in the memory, and that the second determination time for writing operation is the time necessary to write the new data into the memory.

Abstract: The rewriting system for rewriting data stored in a memory of a vehicle controller with new data is provided. The rewriting device is capable of communicating with the vehicle controller. The rewriting device enters a waiting state in which there is no exchange of message between the vehicle controller and the rewriting device. The rewriting device is in a waiting state until a predetermined waiting time has elapsed from the time at which a signal for requesting the vehicle controller to delete the data or write the new data is sent, or from the time at which a signal indicative of start of deleting operation of the data or writing operation of the new data is received. Thus, an erroneous determination of offline due to a busy state of the vehicle controller caused by deleting or writing operation is avoided.

Abstract: A memory rewriting system for a vehicle controller is provided. The memory rewriting system transfers a first program from a rewriting device to the vehicle to rewrite a second program stored in a memory of the vehicle controller with the first program. The first program is transferred as data blocks. Each of the data blocks includes a program code field, a first address field and a second address field. The program code field contains a partial program code of the first program. The first address field contains a leading address of the memory in which the partial program code is stored. The second address field contains a leading address of the memory in which a following partial program code transferred by another block is to be stored. The data blocks are assembled in the rewriting device. Each data block is may be a fixed length or a variable length.

Abstract: The rewriting system for rewriting data stored in a memory of a vehicle controller with new data is provided. The rewriting device is capable of communicating with the vehicle controller. The rewriting device enters a waiting state in which there is no exchange of message between the vehicle controller and the rewriting device. The rewriting device is in a waiting state until a predetermined waiting time has elapsed from the time at which a signal for requesting the vehicle controller to delete the data or write the new data is sent, or from the time at which a signal indicative of start of deleting operation of the data or writing operation of the new data is received. Thus, an erroneous determination of offline due to a busy state of the vehicle controller caused by deleting or writing operation is avoided.

Abstract: The rewriting device for rewriting data stored in a memory of a vehicle controller with new data is provided. The rewriting device is capable of communicating with the vehicle controller. When deleting or writing operation on the memory is not being performed, the rewriting device determines that communication between the rewriting device and the vehicle controller is offline if no response from the vehicle controller within a first determination time. When deleting operation or writing operation on the memory is being performed, the determination of offline is prohibited until a second determination time has elapsed. The second determination time is greater than the first determination time. It is preferable that the second determination time for deleting operation is the time necessary to delete the data stored in the memory, and that the second determination time for writing operation is the time necessary to write the new data into the memory.

Abstract: A memory rewriting system for a vehicle controller is provided. The system comprises a vehicle controller and an external rewriting device. A vehicle controller comprises a rewritable memory storing first security data. The first security data is used to determine whether rewriting to the rewritable memory is permitted. The rewriting device transfers new security data to the vehicle controller. The vehicle controller deletes the first security data and writes the new security data into the rewritable memory. Rewriting the new security data is performed by a program stored in a non-rewritable memory. Thus, the security data that is used to determine whether rewriting to the rewitable memory is permitted is rewritten with the new security data. Therefore, if the existing security data stored in the vehicle controller is invalidated, the security feature of the vehicle can be recovered. The vehicle may includes an anti-theft system.

Abstract: A memory rewriting system for a vehicle controller is provided. The memory rewriting system transfers a first program from a rewriting device to the vehicle to rewrite a second program stored in a memory of the vehicle controller with the first program. The first program is transferred as data blocks. Each of the data blocks includes a program code field, a first address field and a second address field. The program code field contains a partial program code of the first program. The first address field contains a leading address of the memory in which the partial program code is stored. The second address field contains a leading address of the memory in which a following partial program code transferred by another block is to be stored. The data blocks are assembled in the rewriting device. Each data block is may be a fixed length or a variable length.