| 摘要 |
<p>PURPOSE:To prevent the timer interruption request from leaving waiting for a long time unexpectedly, by increasing the interruption level according to the coincidence circuit of an interval timer, in a timer device for timer interruption. CONSTITUTION:A timer interruption interval is set to a preset register 200 from a program and a comparison circuit 300 compares this with the output 120 of an interval timer 100. When coincidence is detected, the interval timer 100 is set to ''0'' and a roll-over counter 500 is counted up via an AND circuit 400. The counter 500 integrates the number of times of coincided detection at the circuit 300, until any instruction from a clear indication signal 410 is given. If this integrated value is not ''0'', a timer interruption signal is outputted from an OR circuit 600 and the priority of interruption is increased according to the integration value 520.</p> |
