| 摘要 |
PURPOSE:To immediately stop the abnormal operation of a servo motor due to the runaway of a microprocessor by inhibiting the output of a PWM unit due to the error detection by providing an error detector for periodically observing a light signal to the PWM unit. CONSTITUTION:An error detector 20 inputs the output pulse of a clock generator 19 and a light signal 12 to a PWM unit 13. Since at least one light signal 12 is input between two continuous clock pulses when a microprocessor 10 normally operates, no error is generated at the output of the detector 20. Since the input of the light signal is eliminated when a malfunction occurs in the microprocessor 10, the output of the detector 20 generates an error. An output inhibitor 21 inhibits the output of the PWM unit 13 by the output. |
