Using more than 4 GPIO pins on the XIAO nRF52840 Sense

[Steppschuh]

@cgwaltney

might be a power brownout issue too

Shouldn’t be a problem if nothing is connected to the pins I guess?

@electry

I consulted the Nordic webpage. The issue is the nRF52840 has only 4 hardware PWM generators

Thanks for investigating, that checks out! I modified my example sketch to verify if I can use pins 4-10 as long as I don’t use more than 4 pins in total - and I can!

@msfujino

If you use non-mbed for BSP, you can use 16 PWMs

Unfortunately I don’t understand what that means, could you elaborate? I tried running your example but only got an error from TinyUSB telling me that the board (Seeed XIAO BLE Sense - nRF52840) is not supported.

@reivilo

time to consider the PCA9685

Thanks for pointing me to this. As @electry suggested, I opted for an IC not manufactured by Adafruit, as I can get 5 for the same price on AliExpress.

I appreciate the input from everyone! To sum up:

It seems to not be possible to output more than 4 PWM signals due to hardware limitations. To work around that, either generate the PWM signal using software or use an external IC like the PCA9685.