51单片机控制步进电机，细分为2，一步为0.9度，走一圈需要400个脉冲，半径为33mm，一圈走0.10362m走20圈需要8000个脉冲。加速为4000个，减速为4000个，定时器0为60ms时周期为7.8s 为40ms时周期为5.2s-51 single-chip stepper motor control, subdivision 2, a step of 0.9 degrees, walk around 400 pulses required radius 33mm, around 20