| 摘要 |
<p>PURPOSE:To improve the accuracy of cycle measurement and the responsiveness of a microcomputer for automobile by using a 2nd latch circuit to hold the relative time of the pulse measured in the previous time in response to the inversion of a pulse to be measured and performing program processing only when it is needed for arithmetic control. CONSTITUTION:A dividing counter 1 integrates clock signals CL as time passes and therefore this integrated value of the clock signals means the relative time. A 1st latch circuit 2 holds the relative time obtained when the pulse to be measured at this time is inverted, i.e., the value of the counter 1 by means of the latch timing signal St synchronous with the inversion of the pulse input signal Si to be measured. While the 2nd latch circuit 7 holds the relative time obtained when the pulse to be measured in the previous time, i.e., the value of the circuit 2 as the signal St. As a result, the relative times of both circuits 2 and 7 are automatically updated for each signal Si. Furthermore, the cycle measuring results of the pulse input signals to be measured are automatically updated by a subtractor 8 in an arithmetic mode for the engine rotational frequency, clutch rotational frequency, the change gear rotational frequency and the driving speed of an automobile respectively.</p> |
