基于单片机的低频相位及频率测量 低频相位及频率计的设计，要求本设计能够实时正确地反映正弦波的频率和相位的数值。-Based on the design the microcontroller low frequency phase and frequency measurement of low-frequency phase and frequency require the design of real time to reflect the values ​ ​ of the sine wave frequency and phase.