Problem Description: Normally, the firmware output a PWM of constant 80% duty cycle and 2.5KHz frequency by PWM1 port. After our device has run several hours, the PWM output change to constant 1% duty cycle and 2.5KHz. The 1% duty must not be set by firmware, it is a abnormal value. I had try to turn off the device and power-on again, and reset the MCU by /RESET pin, but the error state is still held. Then i try to burn the firmware into flash by BDM, the error is removed and the duty of PWM output is normal. Additional, i had check the firmware image by reading from the fault device by BDM, the image is same with the normal one.
Please help to analysis the error. Thanks!