程序功能：STC单片机，开机后，步进电机无动作；按一下s1键，电机正转，按下s2键，电机反转，按下s3键，电机不转

学习重点:

1、步进电机的控掣方法

2、多模块的交互

A组线圈对应 P00

B组线圈对应 P01

C组线圈对应 P02

D组线圈对应 P03-Program features: STC microcontroller, boot, stepper motor no action　s1 button click, the motor is transferred, press s2 key, motor reversal, press s3 key, the motor does not turn Key Points: 1, stepper motor Method 2 control valve, the interactive multi-module A set of coils the coils corresponding to P00 B P01 C corresponds to the coils the coils corresponding to the corresponding P03 P02 D