Vehicle control system and unit for preventing power supply cutoff during re-programming mode
US6138059A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1999 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Feb 25, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/102
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A vehicle electronic control unit (ECU) prevents its power supply from being cut off while it is in the process of re-programming data in a re-programmable nonvolatile memory. An ECU includes a microcomputer which, after receiving a re-program request from a re-programming device, determines if an identification code in a flash memory and an identification code from the re-programming device match. If the codes do match, the microcomputer executes re-program processing for overwriting all the data in the flash memory, including a control program. The ECU is supplied with power from a battery by way of a main relay whose contacts are closed when a vehicle ignition switch (IGSW) is turned on or when a drive signal is applied to the relay. When the IGSW starts to operate, the microcomputer outputs the drive signal to the main relay and, when it completes re-program processing and the IGSW is off, the microcomputer stops outputting the drive signal. Thus even if the IGSW is switched off during execution of re-program processing, power to the microcomputer is maintained so that the re-program processing is not interrupted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.