| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent connector pins from being used for write-in permission/ prohibition control and being in short for its primary purpose of control, to prevent a device from erroneously becoming in a deletion/write-in mode and to improve reliability because the write-in permission/prohibition control of a flash memory is performed by an external control signal in the case of a flash memory built-in CPU. SOLUTION: An input port 5 for allowing/prohibiting deletion/write-in of a flash memory 4 of a CPU 3 is controlled by the CPU 3 itself by outputting a control signal from an output port 6 of the CPU 3. Also, even if the CPU 3 itself controls a port which permits/prohibits the deletion/write-in of the flash memory, when the CPU 3 is in an abnormal state such as runaway, an electric circuit for making a deletion/write-in signal of the input port a prohibition side may be provided instead of a resistor 9.</p> |
