NFC as GPIO on nRF52833

RE: NFC as GPIO on nRF52833

Jonathan — Wed, 15 Dec 2021 15:45:47 GMT

Thank you... I switched to the DK because I could easily put it on the scope.

After your answer, I switch backed to my board and it's actually working. I had just not tried on my board after re-enabling CONFIG_NFCT_PINS_AS_GPIOS .

RE: NFC as GPIO on nRF52833

Jonathan — Wed, 15 Dec 2021 15:14:14 GMT

I'm using the nRF52833-DK, I can't see anything looking like instructions on the bottom side though (also if that matters, I've tried a variety of other GPIOs and they are working fine). Thanks for your help!

RE: NFC as GPIO on nRF52833

Kenneth — Wed, 15 Dec 2021 15:02:09 GMT

Did you also see the last part of my comment:

Additional question; If you are using the nRF52840-DK, are you sure you have followed the description on the back side of the DK in terms of soldering bridges such that the GPIO's are connected to the header?

RE: NFC as GPIO on nRF52833

Jonathan — Wed, 15 Dec 2021 14:44:47 GMT

Reading memory returns:

0x1000120C: FFFFFFFE

(CONFIG_NFCT_PINS_AS_GPIOS is defined in the project, and I still have an extra copy of the code it triggers at the beginning of the project).

Is there anything else that controls NFC/GPIO pins?

RE: NFC as GPIO on nRF52833

Kenneth — Wed, 15 Dec 2021 14:41:10 GMT

I think you should execute the 'nrfjprog --eraseall' and check by reading 'nrfjprog --memrd 0x1000120C --w 32 --n 4' when/if NFC pins are enabled at any time. They should not be enabled if you have added CONFIG_NFCT_PINS_AS_GPIOS in the preprocessor of your project.

Kenneth

RE: NFC as GPIO on nRF52833

Jonathan — Wed, 15 Dec 2021 13:56:56 GMT

Thanks, I tried ("--eraseall") but that didn't change anything...

RE: NFC as GPIO on nRF52833

Kenneth — Wed, 15 Dec 2021 11:45:12 GMT

It may be that you some time in the past have programmed an application that have enabled NFC, hence the NFC pins have been set in UICR. I suggest that you execute an 'nrfjprog --erasell" from command lines to erase the UICR.

Kenneth