本设计利用PIC16F887通过将电位器电压值进行A/D转换，从而对转速给定值进行采样；同时根据脉宽调制原理利用单片机调整输出PWM的高电平时间控制直流电机的转速；电机转速通过利用单片机的CCP捕捉模块捕捉光电遮蔽器产生的脉冲信号，进行计算获得转速，同时将测得的转速与给定值进行比较，对电机的转速进行快速调整，控制电机速度在一定误差范围内；按键模块则实现输入给定速度误差范围，同时LCD能够实时显示电机的转速，实现良好的人机交互。-This design uses the PIC16F887 through the potentiometer voltage value A/D conversion, and thus the speed setpoint sampling　According to the principle of pulse width modulation using a microcontroller to adjust the output PWM high time to control the rotational speed of the DC motor　motor speed byMCU CCP capture module to capture the pulse signal generated by the photoelectric shelter, calculated for speed, while the measured speed with a given value of rapid adjustment of the motor speed control motor speed within a certain error the key module is the input error range for a given speed, while LCD able to display the motor speed to achieve good human-computer interaction.