NFC not working on payment readers

[kian79]

Hi all,

I am using SDK13 with NRF52DK. I am trying to get NFC to work with a reader and encountered some problems.

I have tried 3 different examples, record_text, writable_ndef_msg and wake_on_nfc. They all work properly with an android phone. However, in my application, I need to detect an NFC field from a payment reader. And it seems like only the wake_on_nfc example works. The record_text implements a Type 2 Tag while the writable_ndef_msg implements a Type 4 Tag.

The wake_on_nfc example uses BSP and it seems like it can only be used to wake up the MCU. In my application, my MCU needs to be awake while detecting the presence of a NFC field.

Has anyone managed to get NFC to work with other types of readers other that a mobile phone? Any ideas what I am doing wrong?

Edit: I just need to detect the presence of a NFC field and nothing else. I don't need any exchange of messages.

[Jørgen Holmefjord]

Hi,

The NFCT peripheral will trigger an event if a field is detected when sensing mode is enabled. This short code shows how to enable sensing and interrupt for FIELDDETECTED event:

#include <nrf.h>

// This IRQ handler will trigger when NFC field is detected
void NFCT_IRQHandler(void)
{
  if (NRF_NFCT->EVENTS_FIELDDETECTED == 1)
  {
    NRF_NFCT->EVENTS_FIELDDETECTED = 0;
    //Field detected
  }
}

int main(void)
{
    //Enable interrupt for FIELDDETECT Event
    NRF_NFCT->INTENSET = NFCT_INTENSET_FIELDDETECTED_Enabled << NFCT_INTENSET_FIELDDETECTED_Pos;
    
    //Register interrupt for NFCT module
    NVIC_EnableIRQ(NFCT_IRQn);
    
    //Start sensing 
    NRF_NFCT->TASKS_SENSE = 1;
    while(1)
    {
        // do nothing
    }
}

Best regards,

Jørgen