Aiming at the shortage of resources on microcontroller of optical transceiver module,through the study of PWM mode of GD32E232 timer,the special application mode of PWM,namely single pulse mode,is proposed to be applied to the trigger signal processing circuit of optical transceiver module receiving signal strength indication,which is used to replace the traditional method of configurable logic units circuit.The configuration code of GD32E232 timer's single pulse mode is given in detail.By verifying the input trigger signal of different width,the output signal of fixed width can be obtained.