This article describes the design process and speed DC motor speed control system: use PWM principle, by adjusting the duty cycle of the key motor speed control, the use of the Hall element to measure speed, motor speed and duty cycle up through the liquid crystal display .%本文介绍了直流电机调速和测速系统的设计过程：利用PWM原理，通过按键调节占空比对电机转速进行控制，采用霍尔元件对转速进行测量，电机转速和占空比都通过液晶显示出来。
展开▼
