STM32定时器的基本应用，PWM的的输入捕获，硬件调试通过，基本没有误差。 -The basic application of the STM32 timer, PWM input capture hardware debugging through, basically there is no error.

采用stc15单片的捕获功能测量脉冲周期 精度高 误差小 将测量结果打印到串口显示结果(Stc15 capture function is used to measure the pulse cycle, high accuracy, small error, and print the measurement results to the serial port)