本直流电机PWM调速器主控芯片采用AT89C51，显示部件采用LED数码管，人机交互接口采用独立式键盘，电机驱动电路采用L298。该直流电机PWM调速器能实现电机正转，反转，停止，并能实时显示转动的圈数。-PWM DC motor speed controller of the master chip AT89C51, with LED digital display unit, interactive interface with separate keyboard, the motor dr