Electronic controller for use as controller of vehicle drive machine, has microprocessor operated based on programs stored in magnetic RAM serving as non-volatile memory, and write prevent/enable device enabling write prevent function

摘要

The controller (100A) has a microprocessor (110A) operated based on control programs, which are stored in a magnetic RAM (120A) (MRAM) serving as an electrically readable and writable non-volatile program memory. A write prevent/enable device i.e. logic circuit (150), prevents supply of a write command signal provided by the microprocessor to the MRAM based on a program memory area of the MRAM. The write prevent/enable device enables a write prevent function when an external tool (108) is connected with the microprocessor.