直流电机调速，使用矩阵键盘扫描，52单片机定时器输出PWM，智能控制电机。-DC motor speed control, use the keyboard scan matrix, 52 MCU timer output PWM, intelligent motor control.

直流电机的调速原理，51单片机控制，对于工业应用很有帮助-DC motor speed control principle, 51 MCU control, useful for industrial applications

PWM电机无极调速，用PWM控制直流电机的转动速度，基于51单片机，C语言-PWM motor stepless speed control, the PWM control the rotational speed of the DC motor, based on 51 microcontroller, C language