NFC and LFCLK initialization

[LWittland]

I'm experiencing a problem with the NFC.

I'm trying to make a simple read-only tag, and I've used the NFC Text Record Example to build upon. That worked without a problem.

However, when I integrated the NFC code in my project, I wasn't able to read out the tag any more, the reader said it was empty. However, I got no error code from the nfc library/code.

When I shuffled my code around, I found out that the problem has to do with the low frequency clock configuration I used:

void LFCLK_Config(void)
{
    ret_code_t err_code = nrf_drv_clock_init();
    APP_ERROR_CHECK(err_code);

    nrf_drv_clock_lfclk_request(NULL);
}

If I configure the LFCLK first, the program runs, but the NFC tag is empty. If i configure the NFC first, I'll get a NRF_ERROR_MODULE_ALREADY_INITIALIZED error from the nrf_drv_clock_init() call. Unfortunately, I need the LFCLK to drive my RTC.

I havn't found anything in the documentation that forbits the use of LFCLK when using NFC (using nRF52840, there shouldn't even be the timer 4 restriction).

Is there a way to solve this?

I'm using a nRF52840 and SDK version 15.

I've found the Patch for nrf_nfct_field_event_handler() function and applied it; it made no difference.

Best regards,

     Lasse

[Simon]

Currently, a huge portion of the support team are on christmas vacation, and might not be able to answer you in the closest future. In the first week of 2019 most of the staff will we back and you can expect an answer then.

Best regards,

Simon