| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the wrong write operation of a memory in a microcomputer when the microcomputer is initialized or momentarily stopped. SOLUTION: A flag 12 is set at logical value '1' by an external factor, etc., while the microcomputer is released from its reset mode and a power supply VDD is stabilized. In such a case, a latch circuit 15 is kept in a reset mode to prevent such a case where an EEPROM 1 is set in a write mode. When the VDD is momentarily stopped while an address area B of the EEPROM 1 is rewritten, the circuit 15 is reset and the data rewrite operation is discontinued. Thus the wrong write operations can be prevented.</p> |
