| 摘要 |
<p>PURPOSE:To enable a timer to perform counting operation with accuracy required for each controller and to vary the number of timers according to an applied controller by controlling a timer clock according to timer accuracy reported from a control processing processor. CONSTITUTION:A frequency divider 16 reads a timer accuracy value written in a timer accuracy register 11 by the control processing processor and the operation clock of the timer count part 17 is generated by dividing the frequency of a source clock 15 so that operation is performed with the specified timer accuracy of the time counting part 17. Then the timer count part 17 writes the head address of the head timer of a common memory 13 in a heat timer address register. The tail address of the tail timer is calculated by reading the value, written in a timer quantity register 12 by the control processing processor, by a common memory address signal generating circuit. Those two values are used to determined an address area of the common memory 13 where timer counter values of respective timers are set. Consequently, the timer device which has the specified timer accuracy and consists of a specified number of timers is obtained.</p> |
