| 摘要 |
<p>PROBLEM TO BE SOLVED: To rewrite a program instruction in a non-volatile memory by the internal operation of a microcomputer. SOLUTION: When an operation permission signal *CE and a write permission signal *WE are respectively turned to low levels, a control signal WRT is turned to a high level and a flash memory 2 is turned to a writing state. When the signals *CE, *WE are turned to high levels, a write inhibition signal WI is generated, the control signal WRT is turned to a low level and the flash memory 2 is turned to a write inhibition state. When the signal *CE and a read permission signal *OE are turned to low levers, the control signal WRT is held at the low level, so that the flash memory 2 is turned to a reading state. Thereby, the flash memory 2 can be set up to the writing state and the reading state in a series of program processing processes.</p> |
