| 摘要 |
<p>A digital pulse processing device is capable of selecting precision. The digital pulse processing device includes a counter group for counting pulses output from a pulse output device, the counter group having a plurality of counters 110 and 111 that can be separated from and coupled with each other, a mode control circuit 129 for instructing separation and coupling of the counters 110 and 111, and a control circuit 116 for separating and coupling the counters 110 and 111 in accordance with the instruction of the mode control circuit 129. An overflow condition of the timer 119 is detected using an overflow flag. Detection of an overflow is conducted by setting the flag when an overflow condition has occurred twice or more. The flag is reset by rewriting the state of the flag by a software. An overflow condition which has occurred for the first time is detected in the conventional manner and is treated as carry or borrow. A register 128 is provided to hold the value of the timer 119 when a microcomputer reads in the counter 111. In this way, even when DELTA A(i) = 0, speed detection operation can be executed using the value of the counter 111 obtained synchronously with the counting of the counter 110.</p> |
