RE: PWM is stopping a few seconds after boot

Kenneth — Tue, 17 Aug 2021 11:50:41 GMT

Hi,

It may be difficult to debug exactly what is the problem here. I assume you are using the app_pwm library, which is not using a dedicated pwm hardware module, but instead use a mix of timers, ppi and gpiote to generate a pwm signal. This was originally intended for the nRF51-series which don't have a pwm hardware module.

I suggest to use the dedicated PWM module in the nRF52840 instead of the "soft" implementation above. You can find a simple PWM implementation here:
https://devzone.nordicsemi.com/f/nordic-q-a/28081/is-there-a-simple-example-how-to-set-a-pwm-driver/110654#110654

The example was written for the nRF52832, but can also work on the nRF52840 (both have PWM hardware modules).

As to answer your questions on pan73 and ppi delay workaround, this is a workaround for the nRF51-series and early hardware versions of the nRF52832. It does not have any effect on the nRF52840. If you want to pursue what may be the difference between build codes, it can help to understand which build codes you have found works and fails.

Best regards,
Kenneth