| 摘要 |
PROBLEM TO BE SOLVED: To omit a backup battery and to miniaturize a device by using a memory element. SOLUTION: A DC power circuit 2 connects an encoder 7 to an input port 4 of an MPU 3 via an encoder line 12 and changes an AC power supply 1 into a DC power supply. Then the circuit 2 is connected to an A/D input 5 of the MPU 3 via a power voltage monitor line 11 to monitor the power voltage. Meanwhile, an EEPROM 6 which can store the data with no use of a power supply is connected to the MPU 3 via a position data bus line 10. Furthermore, the MPU 3 is connected to the EEPROM 6 via a write/read control line 9. |
