Using GPIO 10 (NFC pin) to drive SPI SCLK

RE: Using GPIO 10 (NFC pin) to drive SPI SCLK

Reeshma — Tue, 23 May 2017 08:40:31 GMT

ok , thank you, i will refer that one.

RE: Using GPIO 10 (NFC pin) to drive SPI SCLK

Chris — Tue, 23 May 2017 07:54:06 GMT

Hey Reeshma, as Zhouyu above states there is also a #define you can put in your makefile. He mentions one there but I'm not sure if that was the final name... if you look in the startup.s (from memory) file you can find the code that enables the NFC pins as GPIO to find the exact define.. or someone might know it. That means you won't need my code snippet.

RE: Using GPIO 10 (NFC pin) to drive SPI SCLK

Reeshma — Tue, 23 May 2017 07:03:55 GMT

HI , i have followed your above code to use the nfc pin as gpio , but am getting the following error.. main.c:43: undefined reference to `nrf_nvmc_write_word' am using the SDK v 13.0 and compiling it in the arm gcc compiler of linux terminal... can you please say , where am made a mistake...am a beginner to this platform, can you please guide me..

RE: Using GPIO 10 (NFC pin) to drive SPI SCLK

zhouyu — Fri, 29 Jul 2016 06:52:42 GMT

Thanks for your sharing. In addition to your answer, defining CONFIG_NFCT_PINS_AS_GPIOS which was found in system_nrf52.c would work as well.

RE: Using GPIO 10 (NFC pin) to drive SPI SCLK

Chris — Fri, 03 Jun 2016 07:53:59 GMT

No problem, there were a few examples things using uicr_config.h but that didn't work, so thought when I got a snippet that worked it'll help. Such a great forum this is..

RE: Using GPIO 10 (NFC pin) to drive SPI SCLK

MartinBL — Fri, 03 Jun 2016 07:48:52 GMT

Thanks for sharing the solution with us.

RE: Using GPIO 10 (NFC pin) to drive SPI SCLK

Chris — Thu, 02 Jun 2016 23:30:17 GMT

It was fighting with the pin next to it (a small short had developed.. such fine pitch components) so after all these changes and trying on a fresh board there was no problem.

But the useful snippet for getting it into GPIO mode properly is well worth leaving here and the reboot required especially as when you flash these things it's all reset.