| 摘要 |
<p>PURPOSE:To know the time of service interruption and at the same time to ensure a quick reset to the normal time, by stopping the working of a clock counter to hold the service interruption time data when the service is interrupted and counting the number of clocks equivalent to the period of service interruption by means of a different high-speed clock counter. CONSTITUTION:The time of service interruption is known for a data collector, and the processing items which are missed in the period of service interruption. In this case, a time counter CTR1 counts clocks and delivers a time data. When a service interruption is detected, the counter CTR1 stops its counting of clocks and holds the time of service interruptin. A counter CTR2 counts high-speed clocks (1-minute clocks) in place of the CTR1. Then the contents (the number of clocks equivalent to the period of service interruption) of the counter CTR2 are read and applied to the counter CRT1. Thus the time can be reset to the present normal time.</p> |
