本例载波频率为20KHz，或载波周期为50μs。DSP晶振10MHz，内部4倍频，时钟频率为40MHz，计数周期为25ns。假设调制波频率由外部输入（1～50Hz），并转换成合适的格式（本例为Q4格式）。调制系数M为0～0.9。死区时间1.6μs。最小删除脉宽3μs。

主程序的工作是根据输入的调制波频率计算N、2N和M值。

-Example for the carrier frequency 20KHz, or carrier period is 50μs. DSP crystal 10MHz, internal 4 multiplier, the clock frequency of 40MHz, counting cycle 25ns. Assuming wave frequency modulation by external input (1 ~ 50Hz), and converted into an appropriate format (in this case for Q4 format). Modulation coefficient M is 0 ~ 0.9. Dead time 1.6μs. Delete the smallest pulse width 3μs. The work of the main program is based on input frequency modulation wave calculation of N, 2N and M values.