Title:
ELECTRONIC CONTROLLER FOR AUTOMOBILE
Document Type and Number:
Japanese Patent JPS6474601
Kind Code:
A
Abstract:
PURPOSE:To surely prevent abnormal data from being written in a storage part by operating an inhibiting means consisting of hardware at the time of input of a halt signal to inhibit the access to the storage part from an operation processing part. CONSTITUTION:When an operating voltage VCC applied to a CPU 11 is dropped to a prescribed value or lower, an input/output device 12 outputs a halt signal to the CPU 11. When the halt signal is inputted from the device 12, the CPU 11 stops the operation processing of the controlled variable and opens a switch 15. Then, a data bus 14 is opened to inhibit the access from the CPU 11 to a RAM 13, and therefore, abnormal data is surely prevented from being written in the RAM 13 though the voltage VCC cannot detect the halt signal thereafter to cause the abnormal operation of the CPU 11.
Inventors:
TOMIZAWA NAOMI
Application Number:
JP23114387A
Publication Date:
March 20, 1989
Filing Date:
September 17, 1987
Export Citation:
Assignee:
JAPAN ELECTRONIC CONTROL SYST
International Classes:
G05B9/02; B60R16/02; F02D45/00; (IPC1-7): B60R16/02; F02D45/00; G05B9/02
Domestic Patent References:
| JPS61262803A | 1986-11-20 |