NFC-Nrf52 doesn't respond wake-up command if crc check is disabled for rx

RE: NFC-Nrf52 doesn't respond wake-up command if crc check is disabled for rx

FormerMember — Fri, 27 Jan 2017 15:15:13 GMT

I'm sorry for the late response. How were you able to see the correct and incorrect behavior?

RE: NFC-Nrf52 doesn't respond wake-up command if crc check is disabled for rx

Binh — Thu, 12 Jan 2017 15:44:40 GMT

Thanks for the testing :)

But i meant NFC peripheral wakeup and sleep commands. From the nrf52832 spec

The SLP_REQ is automatically handled by the NFC peripheral.

if CRC bit is enabled NFC behavior is correct

| Rdr | 50  00  57  cd     |  ok | SLP_REQ |
| Rdr | 52                 |     | WUPA    | wakeup request
| Tag | 04  00             |     |         | This is the correct response for wakeup request

If CRC bit is disabled then

| Rdr | 50  00  57  cd     |  ok | SLP_REQ |
| Rdr | 52                 |     | WUPA    | wakeup request
| Rdr | 26                 |     | REQA    | Tag doesn't respond, timeout and reader send Reqest command
| Tag | 04  00             |     |         | Tag responds correctly

RE: NFC-Nrf52 doesn't respond wake-up command if crc check is disabled for rx

FormerMember — Thu, 12 Jan 2017 13:49:25 GMT

The following code snipped from wake_on_nfc with NRF_NFCT->RXD.FRAMECONFIG &= ~NFCT_RXD_FRAMECONFIG_CRCMODERX_Msk; added, works fine when I test it here:

int main(void)
{
    utils_setup();
		NRF_NFCT->RXD.FRAMECONFIG &= ~NFCT_RXD_FRAMECONFIG_CRCMODERX_Msk;
    // Turn on LED to indicate that the device entered System ON mode.
    bsp_board_led_on(BSP_BOARD_LED_0);
		
while (true)
{
    if (m_system_off_mode_on)
    {
        nrf_delay_ms(100);
        // Enter System OFF mode.
        NRF_POWER->SYSTEMOFF = 1;
    }
}
}

Is that what you meant, disable CRC and then wake up the chip?

RE: NFC-Nrf52 doesn't respond wake-up command if crc check is disabled for rx

Binh — Wed, 11 Jan 2017 16:42:28 GMT

It is just default value with crc bit disabled.

RE: NFC-Nrf52 doesn't respond wake-up command if crc check is disabled for rx

FormerMember — Wed, 11 Jan 2017 13:08:30 GMT

After doing NRF_NFCT->RXD.FRAMECONFIG &= ~NFCT_RXD_FRAMECONFIG_CRCMODERX_Msk;, what is the register value of RXD.FRAMECONFIG?

RE: NFC-Nrf52 doesn't respond wake-up command if crc check is disabled for rx

Binh — Tue, 10 Jan 2017 06:37:11 GMT

seems that if CRC is disable. Hardware doesn't handle sleep request automatically. So it doesn't response to wake up command.