| 摘要 |
<p>PURPOSE:To speedily transfer data from a main control circuit to a subordinate control circuit at the time of operation by a backup power source. CONSTITUTION:When the output voltage of a power circuit 7 is higher than a prescribed voltage Va, the controller is in operation mode wherein a necessary operation program is executed. The main control circuit 12 enters a stop mode wherein the current consumption is suppressed unless the output voltage reaches the prescribed voltage Va. The subordinate control circuit 13 receives data sent by the main control circuit 12 synchronizing with a data set signal by deciding the level inversion of the leading edge part and trailing edge of the data set signal from certain-period level transition on condition that the output voltage of the power circuit 7 is larger than the prescribed voltage Va, thereby monitoring the operation of the main control circuit 12. When the output voltage is lower than the prescribed voltage Va, on the other hand, the level inversion of the leading edge part and trailing edge part of the data set signal is decided by edge detection and the data are received immediately by interruption, so that the subordinate control circuit performs limited complementary operation instead of the main control circuit 12.</p> |
