可以作为测速来用，用的是在单位时间没对所来的脉冲的个数。两位还有一种方法是对相邻两个脉冲的时间来测量，适合速度变化不大的地方-to be used as a gun, the time is not in the flat on the pulse number. 2 there is a method to two adjacent pulse measurement of the time, the speed of change for the little local