Detect if NFC antenna is connected

RE: Detect if NFC antenna is connected

Menon — Thu, 17 Oct 2024 14:42:30 GMT

Hello,

Toggling the NFC pins between functioning as NFC pins and GPIOs during runtime is not possible. This must be set when building the application. I'm not sure which SDK version you're using, but with NCS version <2.5.0, you can use CONFIG_NFCT_PINS_AS_GPIOS. For NCS >2.6.0, refer this.

Sorry, I shouldn't have used 'not advisable' in my first response. I think it caused some confusion.

Kind Regards,

Abhijith

RE: Detect if NFC antenna is connected

Shahin97 — Tue, 15 Oct 2024 15:18:35 GMT

It'll be only checked during the initialization steps, i.e. once on each boot. NFC is initialized backend, is there a way of disabling NFC on startup and initializing it manually in code?

RE: Detect if NFC antenna is connected

Menon — Tue, 15 Oct 2024 15:13:05 GMT

Hello,

Are you referring to the NFC antennas on the development kit? I’m asking because I find the query a bit unclear.

[quote user=""]My thought process is, set as GPIOs, one as input and one as output set high to measure the continuity. Am I able to toggle NFC between GPIO and NFC in runtime? [/quote]

The nRF52833 uses two dedicated pins for NFC functionality, typically referred to as NFC1 (pin 2) and NFC2 (pin 3). These special-purpose pins are designed for NFC communication but can also be used as GPIOs. However, I believe frequent toggling between NFC and GPIO modes at runtime is not advisable. I think the main reason is that reinitializing the NFC each time you toggle may disrupt its functionality, as NFC seems to be highly sensitive to timing.

Kind Regards,

Abhijith