NFC has no event response issue

[liangzh]

Problem background：

The normal usage environment is for the wristband to swipe the card irregularly. After a period of use, such as 100 units, dozens of units cannot swipe the card, and there is no response when swiping the card. It does not mean that data writing fails, but rather that NFC cannot receive a single message, resulting in complete failure.

After the wristband is placed out of battery, the power on function returns to normal.

Analysis already done：

1. Use the t4t format NFC virtual card, attached are the init function and handle function. The handle does not handle any communication or complex algorithms, only setting some variables.

2. The operation of the card reader on NFC cards is:

       1. Reset the antenna (equivalent to removing the card once)

       2. Card search (equivalent to activating a card and obtaining UID)

       3. Send RATS command (equivalent to switching the card to APDU mode)

       4. Send multiple APDU instructions to read files:

                      Select DF file 

                          00 A4 04 00 07 D2 76 00 00 85 01 00

                     Select MF

                         00 A4 00 0C 02 E1 04

                    Write file (write 2 bytes)

                        00 D6 00 00 02 00 01

3. The conclusion drawn from the testing conducted by the card reader manufacturer is that if the wristband is pulled back in the magnetic field and continues to send instructions, there is a very small probability that it will freeze and fail, with hundreds of repetitions occurring once.

4. Our testing method here is to continuously swipe the card: up to 500+swipes show no response, down to 41 swipes show no response, a total of thousands of swipes, with a median of around 200 swipes showing no response once. When not responding, all messages will not be received.

5. I added a piece of code that executes every 10 minutes

nfc_t4t_emulation_stop();
nrf_delay_ms(20);
nfc_t4t_emulation_start();

When this code exists, any unresponsiveness can be restored.
But currently, the problem has not been identified.

One additional phenomenon: The card reader manufacturer said that when the card reader approaches the NFC card, there will be two exit messages: one is the initial reset antenna, and the other is the final disappearance of the magnetic field. But when I tested it, if my card reader kept sticking to the wristband, the nfc_callback on the 840 side would continuously receive NFC_T4T_EVENT_FIELD_ON，NFC_T4T_EVENT_FIELD_OFF without stopping. I left it for 10 minutes without getting stuck, so I didn't continue studying. I don't know if this phenomenon is helpful for analyzing the problem.

After an exception occurs, the NFC will not trigger any events, including NFC error callbacks, while the chip is still working properly.

Could you please help me check if I know the cause of the problem, or if there are better avoidance and analysis solutions?

[Jørgen Holmefjord]

Hi,

Which SDK version are you using?

Can you reproduce this on a nRF52840 DK, or is it only visible on your custom board?

Can you provide any device logs with debug log level for the NFCT driver enabled, showing the events when this issue occurs?

Best regards,
Jørgen

[Jørgen Holmefjord]

It would be really helpful if you can enable the debug logging like I suggested and provide the device logs from a run where you reproduce the issue.

Also, make sure that you check the return code from all NFC functions in your application, to make sure the device is not put into a unknown state.

If you can provide the full project code, that would also be helpful.

[liangzh]

Hi，

Fullscreen nfc_test.c Download

#include <stdint.h>
#include <stdbool.h>
#include "app_error.h"
#include "app_scheduler.h"
#include "boards.h"
#include "nrfx_nfct.h"
#include "nfc_t4t_lib.h"
#include "nrf_log_ctrl.h"
#include "nrf_delay.h"
#include "nfc_ndef_msg.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

uint32_t nfc_on_count = 0;
uint32_t nfc_off_count = 0;
uint32_t nfc_update_count = 0;

static uint8_t m_ndef_msg_buf[100] = {0};      /**< Buffer for NDEF file. */
static uint8_t m_ndef_msg_len;                      /**< Length of the NDEF message. */

static void nfc_callback(void          * context,
                         nfc_t4t_event_t event,
                         const uint8_t * data,
                         size_t          dataLength,
                         uint32_t        flags)
{
    (void)context;

    switch (event)
    {
        case NFC_T4T_EVENT_FIELD_ON:
			nfc_on_count++;
			NRF_LOG_INFO("NFC_T4T_EVENT_FIELD_ON.");
            NRF_LOG_HEXDUMP_INFO(data, dataLength);
            //bsp_board_led_on(BSP_BOARD_LED_0);
            break;

        case NFC_T4T_EVENT_FIELD_OFF:
			nfc_off_count++;
			NRF_LOG_INFO("NFC_T4T_EVENT_FIELD_OFF.");
            NRF_LOG_HEXDUMP_INFO(data, dataLength);
            //bsp_board_leds_off();
            break;

        case NFC_T4T_EVENT_NDEF_READ:
			NRF_LOG_INFO("NFC_T4T_EVENT_NDEF_READ.");
            NRF_LOG_HEXDUMP_INFO(data, dataLength);
            //bsp_board_led_on(BSP_BOARD_LED_3);
            break;

        case NFC_T4T_EVENT_NDEF_UPDATED:
			nfc_update_count++;
//			if(nfc_update_count>=100)
//			{
//				nfc_reset_evt();
//			}
			NRF_LOG_INFO("NFC_T4T_EVENT_NDEF_UPDATED.%x%x%x",data[0],data[1],data[2]);
           // if (dataLength > 0)
            {
			ret_code_t err_code;
		    NRF_LOG_HEXDUMP_INFO(data, dataLength);
			m_ndef_msg_len = dataLength;
//			if(data[1] == 0xff)
//			{
//				set_standby();
//			}
//			else if(data[1] == 0x00)
//			{
//				out_standby();
//			}
//			//Set_bmp_index(data[1]);
//			bmp_data_evt();
            }
            break;

        default:
            NRF_LOG_HEXDUMP_INFO(data, dataLength);
            break;
    }
}

void nfc_reset_evt(void)
{
    nfc_t4t_emulation_stop();
    nrf_delay_ms(20);
    nfc_t4t_emulation_start();
    nrfx_nfct_state_force(NRFX_NFCT_STATE_ACTIVATED);
}

uint8_t nfc_id[7] = {0};
void init_nfc_t4t(uint8_t* mac)
{
	ret_code_t err_code;

	/* Set up NFC */
	err_code = nfc_t4t_setup(nfc_callback, NULL);
	APP_ERROR_CHECK(err_code);
    
    memcpy(nfc_id,mac,6);
	nfc_t4t_parameter_set(NFC_T4T_PARAM_NFCID1,nfc_id,7);
    
	/* Run Read-Write mode for Type 4 Tag platform */
	err_code = nfc_t4t_ndef_rwpayload_set(m_ndef_msg_buf, sizeof(m_ndef_msg_buf));
	APP_ERROR_CHECK(err_code);

	NRF_LOG_INFO("Writable NDEF message example started.");
    
	/* Start sensing NFC field */
    err_code = nfc_t4t_emulation_start();
	APP_ERROR_CHECK(err_code);

    nrfx_nfct_state_force(NRFX_NFCT_STATE_ACTIVATED);
}

Fullscreen 06402.main.c Download

/**
 * Copyright (c) 2014 - 2021, Nordic Semiconductor ASA
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 *
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 *
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
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 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
/** @file
 *
 * @defgroup ble_sdk_uart_over_ble_main main.c
 * @{
 * @ingroup  ble_sdk_app_nus_eval
 * @brief    UART over BLE application main file.
 *
 * This file contains the source code for a sample application that uses the Nordic UART service.
 * This application uses the @ref srvlib_conn_params module.
 */


#include <stdint.h>
#include <string.h>
#include "nordic_common.h"
#include "nrf.h"
#include "ble_hci.h"
#include "ble_advdata.h"
#include "ble_advertising.h"
#include "ble_conn_params.h"
#include "nrf_sdh.h"
#include "nrf_sdh_soc.h"
#include "nrf_sdh_ble.h"
#include "nrf_ble_gatt.h"
#include "nrf_ble_qwr.h"
#include "app_timer.h"
#include "ble_nus.h"
#include "app_uart.h"
#include "app_util_platform.h"
#include "bsp_btn_ble.h"
#include "nrf_pwr_mgmt.h"

#include "nrf_drv_rtc.h"
#include "nrf_drv_clock.h"

#ifdef BOARD_PCA10040
#include <cm_backtrace.h>
#endif

#if defined (UART_PRESENT)
#include "nrf_uart.h"
#endif
#if defined (UARTE_PRESENT)
#include "nrf_uarte.h"
#endif

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

#define APP_BLE_CONN_CFG_TAG            1                                           /**< A tag identifying the SoftDevice BLE configuration. */

#define DEVICE_NAME                     "Nordic_UART"                               /**< Name of device. Will be included in the advertising data. */
#define NUS_SERVICE_UUID_TYPE           BLE_UUID_TYPE_VENDOR_BEGIN                  /**< UUID type for the Nordic UART Service (vendor specific). */

#define APP_BLE_OBSERVER_PRIO           3                                           /**< Application's BLE observer priority. You shouldn't need to modify this value. */

#define APP_ADV_INTERVAL                64                                          /**< The advertising interval (in units of 0.625 ms. This value corresponds to 40 ms). */

#define APP_ADV_DURATION                3000                                       /**< The advertising duration (180 seconds) in units of 10 milliseconds. */

#define MIN_CONN_INTERVAL               MSEC_TO_UNITS(20, UNIT_1_25_MS)             /**< Minimum acceptable connection interval (20 ms), Connection interval uses 1.25 ms units. */
#define MAX_CONN_INTERVAL               MSEC_TO_UNITS(75, UNIT_1_25_MS)             /**< Maximum acceptable connection interval (75 ms), Connection interval uses 1.25 ms units. */
#define SLAVE_LATENCY                   0                                           /**< Slave latency. */
#define CONN_SUP_TIMEOUT                MSEC_TO_UNITS(4000, UNIT_10_MS)             /**< Connection supervisory timeout (4 seconds), Supervision Timeout uses 10 ms units. */
#define FIRST_CONN_PARAMS_UPDATE_DELAY  APP_TIMER_TICKS(5000)                       /**< Time from initiating event (connect or start of notification) to first time sd_ble_gap_conn_param_update is called (5 seconds). */
#define NEXT_CONN_PARAMS_UPDATE_DELAY   APP_TIMER_TICKS(30000)                      /**< Time between each call to sd_ble_gap_conn_param_update after the first call (30 seconds). */
#define MAX_CONN_PARAMS_UPDATE_COUNT    3                                           /**< Number of attempts before giving up the connection parameter negotiation. */

#define DEAD_BEEF                       0xDEADBEEF                                  /**< Value used as error code on stack dump, can be used to identify stack location on stack unwind. */

#define UART_TX_BUF_SIZE                256                                         /**< UART TX buffer size. */
#define UART_RX_BUF_SIZE                256                                         /**< UART RX buffer size. */


BLE_NUS_DEF(m_nus, NRF_SDH_BLE_TOTAL_LINK_COUNT);                                   /**< BLE NUS service instance. */
NRF_BLE_GATT_DEF(m_gatt);                                                           /**< GATT module instance. */
NRF_BLE_QWR_DEF(m_qwr);                                                             /**< Context for the Queued Write module.*/
BLE_ADVERTISING_DEF(m_advertising);                                                 /**< Advertising module instance. */

static uint16_t   m_conn_handle          = BLE_CONN_HANDLE_INVALID;                 /**< Handle of the current connection. */
static uint16_t   m_ble_nus_max_data_len = BLE_GATT_ATT_MTU_DEFAULT - 3;            /**< Maximum length of data (in bytes) that can be transmitted to the peer by the Nordic UART service module. */
static ble_uuid_t m_adv_uuids[]          =                                          /**< Universally unique service identifier. */
{
    {BLE_UUID_NUS_SERVICE, NUS_SERVICE_UUID_TYPE}
};


/**@brief Function for assert macro callback.
 *
 * @details This function will be called in case of an assert in the SoftDevice.
 *
 * @warning This handler is an example only and does not fit a final product. You need to analyse
 *          how your product is supposed to react in case of Assert.
 * @warning On assert from the SoftDevice, the system can only recover on reset.
 *
 * @param[in] line_num    Line number of the failing ASSERT call.
 * @param[in] p_file_name File name of the failing ASSERT call.
 */
void assert_nrf_callback(uint16_t line_num, const uint8_t * p_file_name)
{
    app_error_handler(DEAD_BEEF, line_num, p_file_name);
}

/**@brief Function for initializing the timer module.
 */
static void timers_init(void)
{
    ret_code_t err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);
}

/**@brief Function for the GAP initialization.
 *
 * @details This function will set up all the necessary GAP (Generic Access Profile) parameters of
 *          the device. It also sets the permissions and appearance.
 */
static void gap_params_init(void)
{
    uint32_t                err_code;
    ble_gap_conn_params_t   gap_conn_params;
    ble_gap_conn_sec_mode_t sec_mode;

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&sec_mode);

    err_code = sd_ble_gap_device_name_set(&sec_mode,
                                          (const uint8_t *) DEVICE_NAME,
                                          strlen(DEVICE_NAME));
    APP_ERROR_CHECK(err_code);

    memset(&gap_conn_params, 0, sizeof(gap_conn_params));

    gap_conn_params.min_conn_interval = MIN_CONN_INTERVAL;
    gap_conn_params.max_conn_interval = MAX_CONN_INTERVAL;
    gap_conn_params.slave_latency     = SLAVE_LATENCY;
    gap_conn_params.conn_sup_timeout  = CONN_SUP_TIMEOUT;

    err_code = sd_ble_gap_ppcp_set(&gap_conn_params);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling Queued Write Module errors.
 *
 * @details A pointer to this function will be passed to each service which may need to inform the
 *          application about an error.
 *
 * @param[in]   nrf_error   Error code containing information about what went wrong.
 */
static void nrf_qwr_error_handler(uint32_t nrf_error)
{
    APP_ERROR_HANDLER(nrf_error);
}


/**@brief Function for handling the data from the Nordic UART Service.
 *
 * @details This function will process the data received from the Nordic UART BLE Service and send
 *          it to the UART module.
 *
 * @param[in] p_evt       Nordic UART Service event.
 */
/**@snippet [Handling the data received over BLE] */
static void nus_data_handler(ble_nus_evt_t * p_evt)
{

    if (p_evt->type == BLE_NUS_EVT_RX_DATA)
    {
        uint32_t err_code;

        NRF_LOG_DEBUG("Received data from BLE NUS. Writing data on UART.");
        NRF_LOG_HEXDUMP_DEBUG(p_evt->params.rx_data.p_data, p_evt->params.rx_data.length);

        for (uint32_t i = 0; i < p_evt->params.rx_data.length; i++)
        {
            do
            {
                err_code = app_uart_put(p_evt->params.rx_data.p_data[i]);
                if ((err_code != NRF_SUCCESS) && (err_code != NRF_ERROR_BUSY))
                {
                    NRF_LOG_ERROR("Failed receiving NUS message. Error 0x%x. ", err_code);
                    APP_ERROR_CHECK(err_code);
                }
            } while (err_code == NRF_ERROR_BUSY);
        }
        if (p_evt->params.rx_data.p_data[p_evt->params.rx_data.length - 1] == '\r')
        {
            while (app_uart_put('\n') == NRF_ERROR_BUSY);
        }
    }

}
/**@snippet [Handling the data received over BLE] */


/**@brief Function for initializing services that will be used by the application.
 */
static void services_init(void)
{
    uint32_t           err_code;
    ble_nus_init_t     nus_init;
    nrf_ble_qwr_init_t qwr_init = {0};

    // Initialize Queued Write Module.
    qwr_init.error_handler = nrf_qwr_error_handler;

    err_code = nrf_ble_qwr_init(&m_qwr, &qwr_init);
    APP_ERROR_CHECK(err_code);

    // Initialize NUS.
    memset(&nus_init, 0, sizeof(nus_init));

    nus_init.data_handler = nus_data_handler;

    err_code = ble_nus_init(&m_nus, &nus_init);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling an event from the Connection Parameters Module.
 *
 * @details This function will be called for all events in the Connection Parameters Module
 *          which are passed to the application.
 *
 * @note All this function does is to disconnect. This could have been done by simply setting
 *       the disconnect_on_fail config parameter, but instead we use the event handler
 *       mechanism to demonstrate its use.
 *
 * @param[in] p_evt  Event received from the Connection Parameters Module.
 */
static void on_conn_params_evt(ble_conn_params_evt_t * p_evt)
{
    uint32_t err_code;

    if (p_evt->evt_type == BLE_CONN_PARAMS_EVT_FAILED)
    {
        err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_CONN_INTERVAL_UNACCEPTABLE);
        APP_ERROR_CHECK(err_code);
    }
}


/**@brief Function for handling errors from the Connection Parameters module.
 *
 * @param[in] nrf_error  Error code containing information about what went wrong.
 */
static void conn_params_error_handler(uint32_t nrf_error)
{
    APP_ERROR_HANDLER(nrf_error);
}


/**@brief Function for initializing the Connection Parameters module.
 */
static void conn_params_init(void)
{
    uint32_t               err_code;
    ble_conn_params_init_t cp_init;

    memset(&cp_init, 0, sizeof(cp_init));

    cp_init.p_conn_params                  = NULL;
    cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
    cp_init.next_conn_params_update_delay  = NEXT_CONN_PARAMS_UPDATE_DELAY;
    cp_init.max_conn_params_update_count   = MAX_CONN_PARAMS_UPDATE_COUNT;
    cp_init.start_on_notify_cccd_handle    = BLE_GATT_HANDLE_INVALID;
    cp_init.disconnect_on_fail             = false;
    cp_init.evt_handler                    = on_conn_params_evt;
    cp_init.error_handler                  = conn_params_error_handler;

    err_code = ble_conn_params_init(&cp_init);
    APP_ERROR_CHECK(err_code);
}

extern void nfc_reset_evt(void);
/**@brief Function for putting the chip into sleep mode.
 *
 * @note This function will not return.
 */
static void sleep_mode_enter(void)
{
//    uint32_t err_code = bsp_indication_set(BSP_INDICATE_IDLE);
//    APP_ERROR_CHECK(err_code);

//    // Prepare wakeup buttons.
//    err_code = bsp_btn_ble_sleep_mode_prepare();
//    APP_ERROR_CHECK(err_code);

    // Go to system-off mode (this function will not return; wakeup will cause a reset).
//    uint32_t err_code = sd_power_system_off();
//    APP_ERROR_CHECK(err_code);
    nfc_reset_evt();
}


/**@brief Function for handling advertising events.
 *
 * @details This function will be called for advertising events which are passed to the application.
 *
 * @param[in] ble_adv_evt  Advertising event.
 */
static void on_adv_evt(ble_adv_evt_t ble_adv_evt)
{
    uint32_t err_code;

    switch (ble_adv_evt)
    {
        case BLE_ADV_EVT_FAST:
//            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING);
//            APP_ERROR_CHECK(err_code);
        NRF_LOG_INFO("BLE_ADV_EVT_FAST.");
            break;
        case BLE_ADV_EVT_IDLE:
            NRF_LOG_INFO("BLE_ADV_EVT_IDLE.");
            for(uint32_t i = 0; i < 32; i++)
            {
                nrf_gpio_cfg_default(i);
            }
            sleep_mode_enter();
            break;
        default:
            break;
    }
}


/**@brief Function for handling BLE events.
 *
 * @param[in]   p_ble_evt   Bluetooth stack event.
 * @param[in]   p_context   Unused.
 */
static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context)
{
    uint32_t err_code;
    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
            NRF_LOG_INFO("Connected");
            err_code = bsp_indication_set(BSP_INDICATE_CONNECTED);
            APP_ERROR_CHECK(err_code);
            m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
            err_code = nrf_ble_qwr_conn_handle_assign(&m_qwr, m_conn_handle);
            APP_ERROR_CHECK(err_code);
            
            
            break;

        case BLE_GAP_EVT_DISCONNECTED:
            NRF_LOG_INFO("Disconnected");
            NRF_LOG_FLUSH();
            // LED indication will be changed when advertising starts.
            m_conn_handle = BLE_CONN_HANDLE_INVALID;
//        *(volatile uint32_t *)0x00400123 = 0x1234;
            break;

        case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
        {
            NRF_LOG_DEBUG("PHY update request.");
            ble_gap_phys_t const phys =
            {
                .rx_phys = BLE_GAP_PHY_AUTO,
                .tx_phys = BLE_GAP_PHY_AUTO,
            };
            err_code = sd_ble_gap_phy_update(p_ble_evt->evt.gap_evt.conn_handle, &phys);
            APP_ERROR_CHECK(err_code);
        } break;

        case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
            // Pairing not supported
            err_code = sd_ble_gap_sec_params_reply(m_conn_handle, BLE_GAP_SEC_STATUS_PAIRING_NOT_SUPP, NULL, NULL);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_SYS_ATTR_MISSING:
            // No system attributes have been stored.
            err_code = sd_ble_gatts_sys_attr_set(m_conn_handle, NULL, 0, 0);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTC_EVT_TIMEOUT:
            // Disconnect on GATT Client timeout event.
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_TIMEOUT:
            // Disconnect on GATT Server timeout event.
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        default:
            // No implementation needed.
            break;
    }
}


/**@brief Function for the SoftDevice initialization.
 *
 * @details This function initializes the SoftDevice and the BLE event interrupt.
 */
static void ble_stack_init(void)
{
    ret_code_t err_code;

    err_code = nrf_sdh_enable_request();
    APP_ERROR_CHECK(err_code);

    // Configure the BLE stack using the default settings.
    // Fetch the start address of the application RAM.
    uint32_t ram_start = 0;
    err_code = nrf_sdh_ble_default_cfg_set(APP_BLE_CONN_CFG_TAG, &ram_start);
    APP_ERROR_CHECK(err_code);

    // Enable BLE stack.
    err_code = nrf_sdh_ble_enable(&ram_start);
    APP_ERROR_CHECK(err_code);

    // Register a handler for BLE events.
    NRF_SDH_BLE_OBSERVER(m_ble_observer, APP_BLE_OBSERVER_PRIO, ble_evt_handler, NULL);
}


/**@brief Function for handling events from the GATT library. */
void gatt_evt_handler(nrf_ble_gatt_t * p_gatt, nrf_ble_gatt_evt_t const * p_evt)
{
    if ((m_conn_handle == p_evt->conn_handle) && (p_evt->evt_id == NRF_BLE_GATT_EVT_ATT_MTU_UPDATED))
    {
        m_ble_nus_max_data_len = p_evt->params.att_mtu_effective - OPCODE_LENGTH - HANDLE_LENGTH;
        NRF_LOG_INFO("Data len is set to 0x%X(%d)", m_ble_nus_max_data_len, m_ble_nus_max_data_len);
    }
    NRF_LOG_DEBUG("ATT MTU exchange completed. central 0x%x peripheral 0x%x",
                  p_gatt->att_mtu_desired_central,
                  p_gatt->att_mtu_desired_periph);
}


/**@brief Function for initializing the GATT library. */
void gatt_init(void)
{
    ret_code_t err_code;

    err_code = nrf_ble_gatt_init(&m_gatt, gatt_evt_handler);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_gatt_att_mtu_periph_set(&m_gatt, NRF_SDH_BLE_GATT_MAX_MTU_SIZE);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling events from the BSP module.
 *
 * @param[in]   event   Event generated by button press.
 */
void bsp_event_handler(bsp_event_t event)
{
    uint32_t err_code;
    switch (event)
    {
        case BSP_EVENT_SLEEP:
            sleep_mode_enter();
            break;

        case BSP_EVENT_DISCONNECT:
            err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            if (err_code != NRF_ERROR_INVALID_STATE)
            {
                APP_ERROR_CHECK(err_code);
            }
            break;

        case BSP_EVENT_WHITELIST_OFF:
            if (m_conn_handle == BLE_CONN_HANDLE_INVALID)
            {
                err_code = ble_advertising_restart_without_whitelist(&m_advertising);
                if (err_code != NRF_ERROR_INVALID_STATE)
                {
                    APP_ERROR_CHECK(err_code);
                }
            }
            break;

        default:
            break;
    }
}


/**@brief   Function for handling app_uart events.
 *
 * @details This function will receive a single character from the app_uart module and append it to
 *          a string. The string will be be sent over BLE when the last character received was a
 *          'new line' '\n' (hex 0x0A) or if the string has reached the maximum data length.
 */
/**@snippet [Handling the data received over UART] */
void uart_event_handle(app_uart_evt_t * p_event)
{
    static uint8_t data_array[BLE_NUS_MAX_DATA_LEN];
    static uint8_t index = 0;
    uint32_t       err_code;

    switch (p_event->evt_type)
    {
        case APP_UART_DATA_READY:
            UNUSED_VARIABLE(app_uart_get(&data_array[index]));
            index++;

            if ((data_array[index - 1] == '\n') ||
                (data_array[index - 1] == '\r') ||
                (index >= m_ble_nus_max_data_len))
            {
                if (index > 1)
                {
                    NRF_LOG_DEBUG("Ready to send data over BLE NUS");
                    NRF_LOG_HEXDUMP_DEBUG(data_array, index);

                    do
                    {
                        uint16_t length = (uint16_t)index;
                        err_code = ble_nus_data_send(&m_nus, data_array, &length, m_conn_handle);
                        if ((err_code != NRF_ERROR_INVALID_STATE) &&
                            (err_code != NRF_ERROR_RESOURCES) &&
                            (err_code != NRF_ERROR_NOT_FOUND))
                        {
                            APP_ERROR_CHECK(err_code);
                        }
                    } while (err_code == NRF_ERROR_RESOURCES);
                }

                index = 0;
            }
            break;

        case APP_UART_COMMUNICATION_ERROR:
            APP_ERROR_HANDLER(p_event->data.error_communication);
            break;

        case APP_UART_FIFO_ERROR:
            APP_ERROR_HANDLER(p_event->data.error_code);
            break;

        default:
            break;
    }
}
/**@snippet [Handling the data received over UART] */


/**@brief  Function for initializing the UART module.
 */
/**@snippet [UART Initialization] */
static void uart_init(void)
{
    uint32_t                     err_code;
    app_uart_comm_params_t const comm_params =
    {
        .rx_pin_no    = RX_PIN_NUMBER,
        .tx_pin_no    = TX_PIN_NUMBER,
        .rts_pin_no   = RTS_PIN_NUMBER,
        .cts_pin_no   = CTS_PIN_NUMBER,
        .flow_control = APP_UART_FLOW_CONTROL_DISABLED,
        .use_parity   = false,
#if defined (UART_PRESENT)
        .baud_rate    = NRF_UART_BAUDRATE_115200
#else
        .baud_rate    = NRF_UARTE_BAUDRATE_115200
#endif
    };

    APP_UART_FIFO_INIT(&comm_params,
                       UART_RX_BUF_SIZE,
                       UART_TX_BUF_SIZE,
                       uart_event_handle,
                       APP_IRQ_PRIORITY_LOWEST,
                       err_code);
    APP_ERROR_CHECK(err_code);
}
/**@snippet [UART Initialization] */


/**@brief Function for initializing the Advertising functionality.
 */
static void advertising_init(void)
{
    uint32_t               err_code;
    ble_advertising_init_t init;

    memset(&init, 0, sizeof(init));

    init.advdata.name_type          = BLE_ADVDATA_FULL_NAME;
    init.advdata.short_name_len     = 7;
    init.advdata.include_appearance = false;
    init.advdata.flags              = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;

    init.srdata.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
    init.srdata.uuids_complete.p_uuids  = m_adv_uuids;

    init.config.ble_adv_fast_enabled  = true;
    init.config.ble_adv_fast_interval = APP_ADV_INTERVAL;
    init.config.ble_adv_fast_timeout  = APP_ADV_DURATION;
    init.evt_handler = on_adv_evt;

    err_code = ble_advertising_init(&m_advertising, &init);
    APP_ERROR_CHECK(err_code);

    ble_advertising_conn_cfg_tag_set(&m_advertising, APP_BLE_CONN_CFG_TAG);
}


/**@brief Function for initializing buttons and leds.
 *
 * @param[out] p_erase_bonds  Will be true if the clear bonding button was pressed to wake the application up.
 */
static void buttons_leds_init(bool * p_erase_bonds)
{
    bsp_event_t startup_event;

    uint32_t err_code = bsp_init(BSP_INIT_LEDS | BSP_INIT_BUTTONS, bsp_event_handler);
    APP_ERROR_CHECK(err_code);

    err_code = bsp_btn_ble_init(NULL, &startup_event);
    APP_ERROR_CHECK(err_code);

    *p_erase_bonds = (startup_event == BSP_EVENT_CLEAR_BONDING_DATA);
}


/**@brief Function for initializing the nrf log module.
 */
static void log_init(void)
{
    ret_code_t err_code = NRF_LOG_INIT(app_timer_cnt_get);
    APP_ERROR_CHECK(err_code);

    NRF_LOG_DEFAULT_BACKENDS_INIT();
}


/**@brief Function for initializing power management.
 */
static void power_management_init(void)
{
    ret_code_t err_code;
    err_code = nrf_pwr_mgmt_init();
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling the idle state (main loop).
 *
 * @details If there is no pending log operation, then sleep until next the next event occurs.
 */
static void idle_state_handle(void)
{
    if (NRF_LOG_PROCESS() == false)
    {
        nrf_pwr_mgmt_run();
    }
}


/**@brief Function for starting advertising.
 */
static void advertising_start(void)
{
    uint32_t err_code = ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
    APP_ERROR_CHECK(err_code);
}
#if NRFX_CHECK(NRFX_RTC2_ENABLED)
const nrf_drv_rtc_t rtc = NRF_DRV_RTC_INSTANCE(2); /**< Declaring an instance of nrf_drv_rtc for RTC0. */

static void rtc_handler(nrf_drv_rtc_int_type_t int_type)
{
    if (int_type == NRFX_RTC_INT_TICK)
    {
        NRF_LOG_INFO("app_timer_cnt_get = %d us.", (int)(app_timer_cnt_get()/ 16384.0 * 1000000) );
    }
}

static void lfclk_config(void)
{
    ret_code_t err_code = nrf_drv_clock_init();
    APP_ERROR_CHECK(err_code);

    nrf_drv_clock_lfclk_request(NULL);
}

static void rtc_config(void)
{
    uint32_t err_code;

    //Initialize RTC instance
    nrf_drv_rtc_config_t config = NRF_DRV_RTC_DEFAULT_CONFIG;
    config.prescaler = 4095;
//    config.tick_latency = NRFX_RTC_US_TO_TICKS(1000000U,4);
    err_code = nrf_drv_rtc_init(&rtc, &config, rtc_handler);
    APP_ERROR_CHECK(err_code);

    nrf_drv_rtc_tick_enable(&rtc,true);

    
    err_code = nrf_drv_rtc_cc_set(&rtc,0,8,true);
    APP_ERROR_CHECK(err_code);

    //Power on RTC instance
    nrf_drv_rtc_enable(&rtc);
}
#endif
uint8_t mac[6] = {0x61,0x52,0x43,0x34,0x25,0x16};
extern void init_nfc_t4t(uint8_t* mac);
/**@brief Application main function.
 */
int main(void)
{
    bool erase_bonds;

    // Initialize.
    uart_init();
//    lfclk_config();
    log_init();
    timers_init();
    init_nfc_t4t(mac);
//    rtc_config();
//    buttons_leds_init(&erase_bonds);
    power_management_init();
    ble_stack_init();
    gap_params_init();
    gatt_init();
    services_init();
    advertising_init();
    conn_params_init();
//    #ifdef BOARD_PCA10040
//    cm_backtrace_init("nrf52832_xxaa", "1.0.0","1.4.0");
//    #endif
    // Start execution.
    printf("\r\nUART started.\r\n");
    NRF_LOG_INFO("Debug logging for UART over RTT started.");
    advertising_start();
    
//    for(uint32_t i = 0; i < 32; i++)
//    {
//        nrf_gpio_cfg_default(i);
//    }
    // Enter main loop.
    for (;;)
    {
        
        idle_state_handle();
    }
}


/**
 * @}
 */

Before chip initialization, if the NFC coil is read by the NFC card reader, there will be an exception where the NFC cannot be started.

From the log information, it appears that there have been interruptions from NFC, but the event has not been processed.

The interference of magnetic fields can cause the timer of NFC to start before nfc_t4_emulation_start, and if no corresponding event is turned off,

Will cause the event callback to remain unable to execute further.

 

<info> app_timer: RTC: initialized.
<info> NFCT: Initialized
<info> app: Writable NDEF message example started.
<debug> NFCT: Field detected
<info> NFCT: Start
<debug> NFCT: Field detected
<info> app: Debug logging for UART over RTT started.
<info> app: BLE_ADV_EVT_FAST.
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<info> app: BLE_ADV_EVT_IDLE.
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected
<debug> NFCT: Field detected

I call this “nrfx_nfct_state_force(NRFX_NFCT_STATE_ACTIVATED);” after initialization to avoid this problem. Will this operation introduce other problems?

void init_nfc_t4t(uint8_t* mac)
{
    ret_code_t err_code;

    /* Set up NFC */
    err_code = nfc_t4t_setup(nfc_callback, NULL);
    APP_ERROR_CHECK(err_code);
    
    memcpy(nfc_id,mac,6);
    nfc_t4t_parameter_set(NFC_T4T_PARAM_NFCID1,nfc_id,7);
    
    /* Run Read-Write mode for Type 4 Tag platform */
    err_code = nfc_t4t_ndef_rwpayload_set(m_ndef_msg_buf, sizeof(m_ndef_msg_buf));
    APP_ERROR_CHECK(err_code);

    NRF_LOG_INFO("Writable NDEF message example started.");
    
    /* Start sensing NFC field */
    err_code = nfc_t4t_emulation_start();
    APP_ERROR_CHECK(err_code);

    nrfx_nfct_state_force(NRFX_NFCT_STATE_ACTIVATED);
}

[liangzh]

Hi Jorgen,

nfc-error.txt

I caught the log with an exception, and I added a label near the exception with "------ ERROR ------".

Could you please help me confirm the cause of the problem? Thank you.

Fullscreen nrfx_nfct(1).c Download

/**
 * Copyright (c) 2018 - 2020, Nordic Semiconductor ASA
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 *
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 *
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <nrfx.h>

#if NRFX_CHECK(NRFX_NFCT_ENABLED)

#include <nrfx_nfct.h>

#define NRFX_LOG_MODULE NFCT
#include <nrfx_log.h>

#if defined(NRF52832_XXAA) || defined(NRF52832_XXAB) || \
    defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
#define USE_TIMER_WORKAROUND
#endif

#if defined(USE_TIMER_WORKAROUND)
#include <nrfx_timer.h>

typedef struct
{
    const nrfx_timer_t timer;                     /**< Timer instance that supports the correct NFC field detection. */
#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
    bool               fieldevents_filter_active; /**< Flag that indicates that the field events are ignored. */
    bool               is_hfclk_on;               /**< HFCLK has started - one of the NFC activation conditions. */
    bool               is_delayed;                /**< Required time delay has passed - one of the NFC activation conditions. */
#else
    uint32_t           field_state_cnt;           /**< Counter of the FIELDLOST events. */
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
} nrfx_nfct_timer_workaround_t;

#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
    #define NRFX_NFCT_ACTIVATE_DELAY     1000 /**< Minimal delay in us between NFC field detection and activation of NFCT. */
    #define NRFX_NFCT_TIMER_PERIOD       NRFX_NFCT_ACTIVATE_DELAY
#else
    #define NRFX_NFCT_FIELDLOST_THR      7
    #define NRFX_NFCT_FIELD_TIMER_PERIOD 100  /**< Field polling period in us. */
    #define NRFX_NFCT_TIMER_PERIOD       NRFX_NFCT_FIELD_TIMER_PERIOD
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
#define NRFX_NFCT_TIMER_INSTANCE         4    /**< Timer instance used for various workarounds for the NFCT HW issues.*/

static nrfx_nfct_timer_workaround_t m_timer_workaround =
{
    .timer = NRFX_TIMER_INSTANCE(NRFX_NFCT_TIMER_INSTANCE),
#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
    .fieldevents_filter_active = false, /**< Flag that indicates that the field events are ignored. */
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
};
#endif // defined(USE_TIMER_WORKAROUND)

#define NRFX_NFCT_FWT_MAX_DIFF         1u             /**< The maximal difference between the requested FWT and HW-limited FWT settings.*/
#define NFCT_FRAMEDELAYMAX_DEFAULT     (0x00001000UL) /**< Default value of the FRAMEDELAYMAX. */

/* Mask of all possible interrupts that are relevant for data reception. */
#define NRFX_NFCT_RX_INT_MASK (NRF_NFCT_INT_RXFRAMESTART_MASK | \
                               NRF_NFCT_INT_RXFRAMEEND_MASK   | \
                               NRF_NFCT_INT_RXERROR_MASK)

/* Mask of all possible interrupts that are relevant for data transmission. */
#define NRFX_NFCT_TX_INT_MASK (NRF_NFCT_INT_TXFRAMESTART_MASK | \
                               NRF_NFCT_INT_TXFRAMEEND_MASK)


/* Mask of all possible errors from the @ref NRF_NFCT_EVENT_RXERROR event. */
#define NRFX_NFCT_FRAME_STATUS_RX_ALL_MASK (NRF_NFCT_RX_FRAME_STATUS_CRC_MASK    | \
                                            NRF_NFCT_RX_FRAME_STATUS_PARITY_MASK | \
                                            NRF_NFCT_RX_FRAME_STATUS_OVERRUN_MASK)

/* Mask of all possible errors from the @ref NRF_NFCT_EVENT_ERROR event. */
#if defined (NRF52832_XXAA) || defined(NRF52832_XXAB)
#define NRFX_NFCT_ERROR_STATUS_ALL_MASK (NRF_NFCT_ERROR_FRAMEDELAYTIMEOUT_MASK | \
                                         NRF_NFCT_ERROR_NFCFIELDTOOSTRONG_MASK | \
                                         NRF_NFCT_ERROR_NFCFIELDTOOWEAK_MASK)
#else
#define NRFX_NFCT_ERROR_STATUS_ALL_MASK (NRF_NFCT_ERROR_FRAMEDELAYTIMEOUT_MASK)
#endif

/* Macros for conversion of bits to bytes. */
#define NRFX_NFCT_BYTES_TO_BITS(_bytes) ((_bytes) << 3)
#define NRFX_NFCT_BITS_TO_BYTES(_bits)  ((_bits)  >> 3)

/* Macro for checking whether the NFCT interrupt is active. */
#define NRFX_NFCT_EVT_ACTIVE(_name) (nrf_nfct_event_check(NRFX_CONCAT_2(NRF_NFCT_EVENT_, _name)) &&        \
                                     nrf_nfct_int_enable_check(NRFX_CONCAT_3(NRF_NFCT_INT_, _name, _MASK)))

/* Macro for callback execution. */
#define NRFX_NFCT_CB_HANDLE(_cb, _evt) \
    if (_cb != NULL)                   \
    {                                  \
        _cb(&_evt);                    \
    }

typedef enum
{
    NRFX_NFC_FIELD_STATE_NONE,   /**< Initial value that indicates no NFCT field events. */
    NRFX_NFC_FIELD_STATE_OFF,    /**< The NFCT FIELDLOST event has been set. */
    NRFX_NFC_FIELD_STATE_ON,     /**< The NFCT FIELDDETECTED event has been set. */
    NRFX_NFC_FIELD_STATE_UNKNOWN /**< Both NFCT field events have been set - ambiguous state. */
} nrfx_nfct_field_state_t;

/**@brief NFCT control block. */
typedef struct
{
    nrfx_nfct_config_t config;
    nrfx_drv_state_t   state;
    volatile bool      field_on;
    uint32_t           frame_delay_max;
} nrfx_nfct_control_block_t;

static nrfx_nfct_control_block_t m_nfct_cb;
static bool nfct_enable = false;
/**
 * @brief Common part of the setup used for the NFCT initialization and reinitialization.
 */
static void nrfx_nfct_hw_init_setup(void)
{
    // Use Window Grid frame delay mode.
    nrf_nfct_frame_delay_mode_set(NRF_NFCT_FRAME_DELAY_MODE_WINDOWGRID);

    /* Begin: Workaround for anomaly 25 */
    /* Workaround for wrong SENSRES values require using SDD00001, but here SDD00100 is used
       because it is required to operate with Windows Phone */
    nrf_nfct_sensres_bit_frame_sdd_set(NRF_NFCT_SENSRES_BIT_FRAME_SDD_00100);
    /* End: Workaround for anomaly 25 */
}

static void nrfx_nfct_frame_delay_max_set(bool default_delay)
{
    if (default_delay)
    {
        nrf_nfct_frame_delay_max_set(NFCT_FRAMEDELAYMAX_DEFAULT);
    }
    else
    {
        nrf_nfct_frame_delay_max_set(m_nfct_cb.frame_delay_max);
    }
}

/**@brief Function for evaluating and handling the NFC field events.
 *
 * @param[in]  field_state  Current field state.
 */
static void nrfx_nfct_field_event_handler(volatile nrfx_nfct_field_state_t field_state)
{
    nrfx_nfct_evt_t nfct_evt;

#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
    if(m_timer_workaround.fieldevents_filter_active)
    {
        return;
    }
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)

    if (field_state == NRFX_NFC_FIELD_STATE_UNKNOWN)
    {
        /* Probe NFC field */
        field_state = (nrfx_nfct_field_check()) ? NRFX_NFC_FIELD_STATE_ON : NRFX_NFC_FIELD_STATE_OFF;
    }
	NRFX_LOG_DEBUG("field_state = %02X",field_state);
    /* Field event service. Only take action on field transition -
     * based on the value of m_nfct_cb.field_on
     */
    switch (field_state)
    {
        case NRFX_NFC_FIELD_STATE_ON:
            if (!m_nfct_cb.field_on)
            {
#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
                /* Begin: Workaround for anomaly 190 */
                m_timer_workaround.is_hfclk_on               = false;
                m_timer_workaround.is_delayed                = false;
                m_timer_workaround.fieldevents_filter_active = true;

                nrfx_timer_clear(&m_timer_workaround.timer);
                nrfx_timer_enable(&m_timer_workaround.timer);
                /* End: Workaround for anomaly 190 */
#elif defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
                nrfx_timer_clear(&m_timer_workaround.timer);
                nrfx_timer_enable(&m_timer_workaround.timer);
                m_timer_workaround.field_state_cnt = 0;  
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)

                m_nfct_cb.field_on = true;
                nfct_evt.evt_id    = NRFX_NFCT_EVT_FIELD_DETECTED;
                NRFX_NFCT_CB_HANDLE(m_nfct_cb.config.cb, nfct_evt);
            }
            break;

        case NRFX_NFC_FIELD_STATE_OFF:
            if (m_nfct_cb.field_on)
            {
                nrf_nfct_task_trigger(NRF_NFCT_TASK_SENSE);
                nrf_nfct_int_disable(NRFX_NFCT_RX_INT_MASK | NRFX_NFCT_TX_INT_MASK);
                m_nfct_cb.field_on = false;
                nfct_evt.evt_id    = NRFX_NFCT_EVT_FIELD_LOST;

                /* Begin: Workaround for anomaly 218 */
                nrfx_nfct_frame_delay_max_set(true);
                /* End: Workaround for anomaly 218 */

                NRFX_NFCT_CB_HANDLE(m_nfct_cb.config.cb, nfct_evt);
            }
            break;

        default:
            /* No implementation required */
            break;
    }
}

#if defined(USE_TIMER_WORKAROUND)

#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
static void nrfx_nfct_activate_check(void)
{
    static bool is_field_validation_pending = false;
    NRFX_LOG_DEBUG("is_field_validation_pending %d, is_hfclk_on = %d, is_delayed = %d",
        is_field_validation_pending, m_timer_workaround.is_hfclk_on, m_timer_workaround.is_delayed);
    if (is_field_validation_pending)
    {
        is_field_validation_pending                  = false;
        m_timer_workaround.fieldevents_filter_active = false;

        // Check the field status and take action if field is lost.
        nrfx_nfct_field_event_handler(NRFX_NFC_FIELD_STATE_UNKNOWN);
        return;
    }

    if ((m_timer_workaround.is_hfclk_on) && (m_timer_workaround.is_delayed))
    {
        nrf_nfct_task_trigger(NRF_NFCT_TASK_ACTIVATE);
        is_field_validation_pending = true;

        // Start the timer second time to validate whether the tag has locked to the field.
        nrfx_timer_clear(&m_timer_workaround.timer);
        nrfx_timer_enable(&m_timer_workaround.timer);
    }
}
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)

#if defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
/* Begin: Workaround for anomaly 116 */
static inline void nrfx_nfct_reset(void)
{
    uint32_t                       fdm;
    uint32_t                       int_enabled;
    uint8_t                        nfcid1[NRF_NFCT_SENSRES_NFCID1_SIZE_TRIPLE];
    nrf_nfct_sensres_nfcid1_size_t nfcid1_size;
    nrf_nfct_selres_protocol_t     protocol;

    // Save parameter settings before the reset of the NFCT peripheral.
    fdm         = nrf_nfct_frame_delay_max_get();
    nfcid1_size = nrf_nfct_nfcid1_get(nfcid1);
    protocol    = nrf_nfct_selsres_protocol_get();
    int_enabled = nrf_nfct_int_enable_get();

    // Reset the NFCT peripheral.
    *(volatile uint32_t *)0x40005FFC = 0;
    *(volatile uint32_t *)0x40005FFC;
    *(volatile uint32_t *)0x40005FFC = 1;

    // Restore parameter settings after the reset of the NFCT peripheral.
    nrf_nfct_frame_delay_max_set(fdm);
    nrf_nfct_nfcid1_set(nfcid1, nfcid1_size);
    nrf_nfct_selres_protocol_set(protocol);

    // Restore general HW configuration.
    nrfx_nfct_hw_init_setup();

    // Restore interrupts.
    nrf_nfct_int_enable(int_enabled);

    // Disable interrupts associated with data exchange.
    nrf_nfct_int_disable(NRFX_NFCT_RX_INT_MASK | NRFX_NFCT_TX_INT_MASK);

    NRFX_LOG_INFO("Reinitialize");
}
/* End: Workaround for anomaly 116 */

static void nrfx_nfct_field_poll(void)
{
    if (!nrfx_nfct_field_check())
    {
        if (++m_timer_workaround.field_state_cnt > NRFX_NFCT_FIELDLOST_THR)
        {
            nrfx_nfct_evt_t nfct_evt =
            {
                .evt_id = NRFX_NFCT_EVT_FIELD_LOST,
            };

            nrfx_timer_disable(&m_timer_workaround.timer);
            m_nfct_cb.field_on = false;

            /* Begin: Workaround for anomaly 218 */
            nrfx_nfct_frame_delay_max_set(true);
            /* End: Workaround for anomaly 218 */

            /* Begin: Workaround for anomaly 116 */
            /* resume the NFCT to initialized state */
            nrfx_nfct_reset();
            /* End: Workaround for anomaly 116 */

            NRFX_NFCT_CB_HANDLE(m_nfct_cb.config.cb, nfct_evt);
        }
        return;
    }

    m_timer_workaround.field_state_cnt = 0;
}
#endif // defined(NRF52832_XXAA) || defined(NRF52832_XXAB)

static void nrfx_nfct_field_timer_handler(nrf_timer_event_t event_type, void * p_context)
{
    (void)p_context;

    if (event_type != NRF_TIMER_EVENT_COMPARE0)
    {
        return;
    }

#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
    m_timer_workaround.is_delayed = true;

    nrfx_timer_disable(&m_timer_workaround.timer);
    nrfx_nfct_activate_check();
    NRFX_LOG_DEBUG("is_hfclk_on = %d, is_delayed = %d",
        m_timer_workaround.is_hfclk_on, m_timer_workaround.is_delayed);
#else
    nrfx_nfct_field_poll();
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
}

static inline nrfx_err_t nrfx_nfct_field_timer_config(void)
{
    nrfx_err_t          err_code;
    nrfx_timer_config_t timer_cfg =
    {
        .frequency          = NRF_TIMER_FREQ_1MHz,
        .mode               = NRF_TIMER_MODE_TIMER,
        .bit_width          = NRF_TIMER_BIT_WIDTH_16,
        .interrupt_priority = NRFX_NFCT_CONFIG_IRQ_PRIORITY
    };

    err_code = nrfx_timer_init(&m_timer_workaround.timer, &timer_cfg, nrfx_nfct_field_timer_handler);
    if (err_code != NRFX_SUCCESS)
    {
        return err_code;
    }

    nrfx_timer_extended_compare(&m_timer_workaround.timer,
                                NRF_TIMER_CC_CHANNEL0,
                                nrfx_timer_us_to_ticks(&m_timer_workaround.timer, NRFX_NFCT_TIMER_PERIOD),
                                NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
                                true);
    return err_code;
}
#endif // defined(USE_TIMER_WORKAROUND)

static inline nrf_nfct_sensres_nfcid1_size_t nrf_nfct_nfcid1_size_to_sensres_size(uint8_t nfcid1_size)
{
    switch (nfcid1_size)
    {
        case NRFX_NFCT_NFCID1_SINGLE_SIZE:
            return NRF_NFCT_SENSRES_NFCID1_SIZE_SINGLE;

        case NRFX_NFCT_NFCID1_DOUBLE_SIZE:
            return NRF_NFCT_SENSRES_NFCID1_SIZE_DOUBLE;

        case NRFX_NFCT_NFCID1_TRIPLE_SIZE:
            return NRF_NFCT_SENSRES_NFCID1_SIZE_TRIPLE;

        default:
            return NRF_NFCT_SENSRES_NFCID1_SIZE_DOUBLE;
    }
}

static inline void nrfx_nfct_rxtx_int_enable(uint32_t rxtx_int_mask)
{
    nrf_nfct_int_enable(rxtx_int_mask & m_nfct_cb.config.rxtx_int_mask);
}

nrfx_err_t nrfx_nfct_init(nrfx_nfct_config_t const * p_config)
{
    NRFX_ASSERT(p_config);

    nrfx_err_t err_code = NRFX_SUCCESS;

    if (m_nfct_cb.state != NRFX_DRV_STATE_UNINITIALIZED)
    {
        return NRFX_ERROR_INVALID_STATE;
    }

    m_nfct_cb.config = *p_config;
    nrfx_nfct_hw_init_setup();

    NRFX_IRQ_PENDING_CLEAR(NFCT_IRQn);
    NRFX_IRQ_PRIORITY_SET(NFCT_IRQn, NRFX_NFCT_CONFIG_IRQ_PRIORITY);
    NRFX_IRQ_ENABLE(NFCT_IRQn);

#if defined(USE_TIMER_WORKAROUND)
    /* Initialize Timer module as the workaround for NFCT HW issues. */
    err_code = nrfx_nfct_field_timer_config();
#endif // defined(USE_TIMER_WORKAROUND)

    if (err_code == NRFX_SUCCESS)
    {
        uint8_t default_nfcid1[NRFX_NFCT_NFCID1_DEFAULT_LEN];
        err_code = nrfx_nfct_nfcid1_default_bytes_get(default_nfcid1, sizeof(default_nfcid1));
        NRFX_ASSERT(err_code == NRFX_SUCCESS);
        nrf_nfct_nfcid1_set(default_nfcid1, NRF_NFCT_SENSRES_NFCID1_SIZE_DEFAULT);
    }
    else
    {
        return err_code;
    }

    m_nfct_cb.state           = NRFX_DRV_STATE_INITIALIZED;
    m_nfct_cb.frame_delay_max = NFCT_FRAMEDELAYMAX_DEFAULT;

    NRFX_LOG_INFO("Initialized");
    return err_code;
}

void nrfx_nfct_uninit(void)
{
    nrfx_nfct_disable();

    NRFX_IRQ_DISABLE(NFCT_IRQn);
    NRFX_IRQ_PENDING_CLEAR(NFCT_IRQn);

#if defined(USE_TIMER_WORKAROUND)
    /* De-initialize Timer module as the workaround for NFCT HW issues. */
    nrfx_timer_uninit(&m_timer_workaround.timer);
#endif // defined(USE_TIMER_WORKAROUND)

    m_nfct_cb.state = NRFX_DRV_STATE_UNINITIALIZED;
    NRFX_LOG_INFO("Uninitialized");
}

void nrfx_nfct_enable(void)
{
    nrf_nfct_error_status_clear(NRFX_NFCT_ERROR_STATUS_ALL_MASK);
    nrf_nfct_task_trigger(NRF_NFCT_TASK_SENSE);

    nrf_nfct_int_enable(NRF_NFCT_INT_FIELDDETECTED_MASK | NRF_NFCT_INT_ERROR_MASK |
                        NRF_NFCT_INT_SELECTED_MASK);
#if !defined(NRF52832_XXAA) && !defined(NRF52832_XXAB)
    nrf_nfct_int_enable(NRF_NFCT_INT_FIELDLOST_MASK);
#endif // !defined(NRF52832_XXAA) && !defined(NRF52832_XXAB)
NRFX_LOG_DEBUG("nrfx_nfct_enable nfct_enable = %d",nfct_enable);
    nfct_enable = true;
	NRFX_LOG_DEBUG("after assignment nfct_enable = %d",nfct_enable);
    NRFX_LOG_INFO("Start");
}

void nrfx_nfct_disable(void)
{
    nrf_nfct_int_disable(NRF_NFCT_DISABLE_ALL_INT);
    nrf_nfct_task_trigger(NRF_NFCT_TASK_DISABLE);
	NRFX_LOG_DEBUG("nrfx_nfct_disable nfct_enable = %d",nfct_enable);
    nfct_enable = false;
	NRFX_LOG_DEBUG("after assignment nfct_enable = %d",nfct_enable);
    NRFX_LOG_INFO("Stop");
}

bool nrfx_nfct_field_check(void)
{
    uint32_t const field_state = nrf_nfct_field_status_get();

    if (((field_state & NRF_NFCT_FIELD_STATE_PRESENT_MASK) == 0) &&
        ((field_state & NRF_NFCT_FIELD_STATE_LOCK_MASK) == 0))
    {
        /* Field is not active */
        return false;
    }

    return true;
}

void nrfx_nfct_rx(nrfx_nfct_data_desc_t const * p_tx_data)
{
    NRFX_ASSERT(p_tx_data);

    nrf_nfct_rxtx_buffer_set((uint8_t *) p_tx_data->p_data, p_tx_data->data_size);

    nrfx_nfct_rxtx_int_enable(NRFX_NFCT_RX_INT_MASK);
    nrf_nfct_task_trigger(NRF_NFCT_TASK_ENABLERXDATA);
}

nrfx_err_t nrfx_nfct_tx(nrfx_nfct_data_desc_t const * p_tx_data,
                        nrf_nfct_frame_delay_mode_t   delay_mode)
{
    NRFX_ASSERT(p_tx_data);
    NRFX_ASSERT(p_tx_data->p_data);

    if (p_tx_data->data_size == 0)
    {
        return NRFX_ERROR_INVALID_LENGTH;
    }

    nrf_nfct_rxtx_buffer_set((uint8_t *) p_tx_data->p_data, p_tx_data->data_size);
    nrf_nfct_tx_bits_set(NRFX_NFCT_BYTES_TO_BITS(p_tx_data->data_size));
    nrf_nfct_frame_delay_mode_set((nrf_nfct_frame_delay_mode_t) delay_mode);

    nrfx_nfct_rxtx_int_enable(NRFX_NFCT_TX_INT_MASK);
    nrf_nfct_task_trigger(NRF_NFCT_TASK_STARTTX);

    NRFX_LOG_INFO("Tx start");
    return NRFX_SUCCESS;
}

void nrfx_nfct_state_force(nrfx_nfct_state_t state)
{
#if defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
    if (state == NRFX_NFCT_STATE_ACTIVATED)
    {
        m_timer_workaround.is_hfclk_on = true;
        /* NFCT will be activated based on additional conditions */
        nrfx_nfct_activate_check();
        return;
    }
#endif // defined(NRF52833_XXAA) || defined(NRF52840_XXAA)
    nrf_nfct_task_trigger((nrf_nfct_task_t) state);
}

void nrfx_nfct_init_substate_force(nrfx_nfct_active_state_t sub_state)
{
    if (sub_state == NRFX_NFCT_ACTIVE_STATE_DEFAULT)
    {
#if defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
        if (((*(uint32_t volatile *)(0x40005420)) & 0x1UL) == (1UL))
#else
        if (nrf_nfct_sleep_state_get() == NRF_NFCT_SLEEP_STATE_SLEEP_A)
#endif //defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
        {
            // Default state is SLEEP_A
            nrf_nfct_task_trigger(NRF_NFCT_TASK_GOSLEEP);
        }
        else
        {
            // Default state is IDLE
            nrf_nfct_task_trigger(NRF_NFCT_TASK_GOIDLE);
        }
    }
    else
    {
        nrf_nfct_task_trigger((nrf_nfct_task_t) sub_state);
    }

    /* Begin: Workaround for anomaly 218 */
    nrfx_nfct_frame_delay_max_set(true);
    /* End: Workaround for anomaly 218 */

    /* Disable TX/RX here (will be enabled at SELECTED) */
    nrf_nfct_int_disable(NRFX_NFCT_RX_INT_MASK | NRFX_NFCT_TX_INT_MASK);
}

nrfx_err_t nrfx_nfct_parameter_set(nrfx_nfct_param_t const * p_param)
{
    NRFX_ASSERT(p_param);
    NRFX_LOG_DEBUG("[%s]:%d",__func__ ,p_param->id);
    switch (p_param->id)
    {
        case NRFX_NFCT_PARAM_ID_FDT:
        {
            uint32_t delay     = p_param->data.fdt;
            uint32_t delay_thr = NFCT_FRAMEDELAYMAX_FRAMEDELAYMAX_Msk;

            // Delay validation.
            if (delay > (delay_thr + NRFX_NFCT_FWT_MAX_DIFF))
            {
                return NRFX_ERROR_INVALID_PARAM;
            }

            delay = (delay > delay_thr) ? delay_thr : delay;
            m_nfct_cb.frame_delay_max = delay;
            break;
        }

        case NRFX_NFCT_PARAM_ID_SEL_RES:
            if (p_param->data.sel_res_protocol > NRF_NFCT_SELRES_PROTOCOL_NFCDEP_T4AT)
            {
                return NRFX_ERROR_INVALID_PARAM;
            }

            nrf_nfct_selres_protocol_set((nrf_nfct_selres_protocol_t) p_param->data.sel_res_protocol);
            break;

        case NRFX_NFCT_PARAM_ID_NFCID1:
        {
            nrf_nfct_sensres_nfcid1_size_t id_size_mask;

            id_size_mask = nrf_nfct_nfcid1_size_to_sensres_size(p_param->data.nfcid1.id_size);
            nrf_nfct_nfcid1_set(p_param->data.nfcid1.p_id, id_size_mask);
            break;
        }

        default:
            break;
    }

    return NRFX_SUCCESS;
}

nrfx_err_t nrfx_nfct_nfcid1_default_bytes_get(uint8_t * const p_nfcid1_buff,
                                              uint32_t        nfcid1_buff_len)
{
    NRFX_LOG_DEBUG("[%s]:%d",__func__ ,nfcid1_buff_len);
    if ((nfcid1_buff_len != NRFX_NFCT_NFCID1_SINGLE_SIZE) &&
        (nfcid1_buff_len != NRFX_NFCT_NFCID1_DOUBLE_SIZE) &&
        (nfcid1_buff_len != NRFX_NFCT_NFCID1_TRIPLE_SIZE))
    {
        return NRFX_ERROR_INVALID_LENGTH;
    }

    uint32_t nfc_tag_header0 = NRF_FICR->NFC.TAGHEADER0;
    uint32_t nfc_tag_header1 = NRF_FICR->NFC.TAGHEADER1;
    uint32_t nfc_tag_header2 = NRF_FICR->NFC.TAGHEADER2;

    p_nfcid1_buff[0] = (uint8_t) (nfc_tag_header0 >> 0);
    p_nfcid1_buff[1] = (uint8_t) (nfc_tag_header0 >> 8);
    p_nfcid1_buff[2] = (uint8_t) (nfc_tag_header0 >> 16);
    p_nfcid1_buff[3] = (uint8_t) (nfc_tag_header1 >> 0);

    if (nfcid1_buff_len != NRFX_NFCT_NFCID1_SINGLE_SIZE)
    {
        p_nfcid1_buff[4] = (uint8_t) (nfc_tag_header1 >> 8);
        p_nfcid1_buff[5] = (uint8_t) (nfc_tag_header1 >> 16);
        p_nfcid1_buff[6] = (uint8_t) (nfc_tag_header1 >> 24);

        if (nfcid1_buff_len == NRFX_NFCT_NFCID1_TRIPLE_SIZE)
        {
            p_nfcid1_buff[7] = (uint8_t) (nfc_tag_header2 >> 0);
            p_nfcid1_buff[8] = (uint8_t) (nfc_tag_header2 >> 8);
            p_nfcid1_buff[9] = (uint8_t) (nfc_tag_header2 >> 16);
        }
        /* Begin: Workaround for anomaly 181. */
        /* Workaround for wrong value in NFCID1. Value 0x88 cannot be used as byte 3
           of a double-size NFCID1, according to the NFC Forum Digital Protocol specification. */
        else if (p_nfcid1_buff[3] == 0x88)
        {
            p_nfcid1_buff[3] |= 0x11;
        }
        /* End: Workaround for anomaly 181 */
    }

    return NRFX_SUCCESS;
}


void nrfx_nfct_autocolres_enable(void)
{
#if defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
    (*(uint32_t *)(0x4000559C)) &= (~(0x1UL));
#else
    nrf_nfct_autocolres_enable();
#endif //defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
}

void nrfx_nfct_autocolres_disable(void)
{
#if defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
    (*(uint32_t *)(0x4000559C)) |= (0x1UL);
#else
    nrf_nfct_autocolres_disable();
#endif //defined(NRF52832_XXAA) || defined(NRF52832_XXAB)
}

void nrfx_nfct_irq_handler(void)
{
    nrfx_nfct_field_state_t current_field = NRFX_NFC_FIELD_STATE_NONE;

    if (NRFX_NFCT_EVT_ACTIVE(FIELDDETECTED))
    {
        nrf_nfct_event_clear(NRF_NFCT_EVENT_FIELDDETECTED);
        current_field = NRFX_NFC_FIELD_STATE_ON;

        NRFX_LOG_DEBUG("Field detected");
    }

#if !defined(NRF52832_XXAA) && !defined(NRF52832_XXAB)
    if (NRFX_NFCT_EVT_ACTIVE(FIELDLOST))
    {
        nrf_nfct_event_clear(NRF_NFCT_EVENT_FIELDLOST);
        current_field = (current_field == NRFX_NFC_FIELD_STATE_NONE) ?
                        NRFX_NFC_FIELD_STATE_OFF : NRFX_NFC_FIELD_STATE_UNKNOWN;

        NRFX_LOG_DEBUG("Field lost");
    }
#endif //!defined(NRF52832_XXAA) && !defined(NRF52832_XXAB)
NRFX_LOG_DEBUG("nrfx_nfct_irq_handler nfct_enable = %d",nfct_enable);
    /* Perform actions if any FIELD event is active */
    if ((current_field != NRFX_NFC_FIELD_STATE_NONE) && (nfct_enable))
    {
        NRFX_LOG_DEBUG("current_field = %02X", current_field);
        nrfx_nfct_field_event_handler(current_field);
    }

    if (NRFX_NFCT_EVT_ACTIVE(RXFRAMEEND))
    {
        nrf_nfct_event_clear(NRF_NFCT_EVENT_RXFRAMEEND);

        nrfx_nfct_evt_t nfct_evt =
        {
            .evt_id = NRFX_NFCT_EVT_RX_FRAMEEND
        };

        /* Take into account only the number of whole bytes. */
        nfct_evt.params.rx_frameend.rx_status         = 0;
        nfct_evt.params.rx_frameend.rx_data.p_data    = nrf_nfct_rxtx_buffer_get();
        nfct_evt.params.rx_frameend.rx_data.data_size = NRFX_NFCT_BITS_TO_BYTES(nrf_nfct_rx_bits_get(true));

        if (NRFX_NFCT_EVT_ACTIVE(RXERROR))
        {
            nfct_evt.params.rx_frameend.rx_status = 
                (nrf_nfct_rx_frame_status_get() & NRFX_NFCT_FRAME_STATUS_RX_ALL_MASK);
            nrf_nfct_event_clear(NRF_NFCT_EVENT_RXERROR);

            NRFX_LOG_DEBUG("Rx error (0x%x)", (unsigned int) nfct_evt.params.rx_frameend.rx_status);

            /* Clear rx frame status */
            nrf_nfct_rx_frame_status_clear(NRFX_NFCT_FRAME_STATUS_RX_ALL_MASK);
        }

        NRFX_NFCT_CB_HANDLE(m_nfct_cb.config.cb, nfct_evt);

        /* Clear TXFRAMESTART EVENT so it can be checked in hal_nfc_send */
        nrf_nfct_event_clear(NRF_NFCT_EVENT_TXFRAMESTART);

        NRFX_LOG_DEBUG("Rx fend");
    }

    if (NRFX_NFCT_EVT_ACTIVE(TXFRAMEEND))
    {
        nrf_nfct_event_clear(NRF_NFCT_EVENT_TXFRAMEEND);

        nrfx_nfct_evt_t nfct_evt =
        {
            .evt_id = NRFX_NFCT_EVT_TX_FRAMEEND
        };

        /* Disable TX END event to ignore frame transmission other than READ response */
        nrf_nfct_int_disable(NRFX_NFCT_TX_INT_MASK);

        NRFX_NFCT_CB_HANDLE(m_nfct_cb.config.cb, nfct_evt);

        NRFX_LOG_DEBUG("Tx fend");
    }

    if (NRFX_NFCT_EVT_ACTIVE(SELECTED))
    {
        nrf_nfct_event_clear(NRF_NFCT_EVENT_SELECTED);
        /* Clear also RX END and RXERROR events because SW does not take care of 
           commands that were received before selecting the tag. */
        nrf_nfct_event_clear(NRF_NFCT_EVENT_RXFRAMEEND);
        nrf_nfct_event_clear(NRF_NFCT_EVENT_RXERROR);
        nrf_nfct_event_clear(NRF_NFCT_EVENT_TXFRAMESTART);
        nrf_nfct_event_clear(NRF_NFCT_EVENT_TXFRAMEEND);

        /* Begin: Workaround for anomaly 218 */
        nrfx_nfct_frame_delay_max_set(false);
        /* End: Workaround for anomaly 218 */

        /* At this point any previous error status can be ignored. */
        nrf_nfct_rx_frame_status_clear(NRFX_NFCT_FRAME_STATUS_RX_ALL_MASK);
        nrf_nfct_error_status_clear(NRFX_NFCT_ERROR_STATUS_ALL_MASK);

        nrfx_nfct_evt_t nfct_evt =
        {
            .evt_id = NRFX_NFCT_EVT_SELECTED
        };
        NRFX_NFCT_CB_HANDLE(m_nfct_cb.config.cb, nfct_evt);

        NRFX_LOG_DEBUG("Selected");
    }

    if (NRFX_NFCT_EVT_ACTIVE(ERROR))
    {
        uint32_t err_status = nrf_nfct_error_status_get();
        nrf_nfct_event_clear(NRF_NFCT_EVENT_ERROR);

        nrfx_nfct_evt_t nfct_evt =
        {
            .evt_id = NRFX_NFCT_EVT_ERROR
        };

        /* Clear FRAMEDELAYTIMEOUT error (expected HW behaviour) when SLP_REQ command was received. */
        if (err_status & NRF_NFCT_ERROR_FRAMEDELAYTIMEOUT_MASK)
        {
            nrf_nfct_error_status_clear(NRF_NFCT_ERROR_FRAMEDELAYTIMEOUT_MASK);

            nfct_evt.params.error.reason = NRFX_NFCT_ERROR_FRAMEDELAYTIMEOUT;
            NRFX_NFCT_CB_HANDLE(m_nfct_cb.config.cb, nfct_evt);
        }

        /* Report any other error. */
        err_status &= ~NRF_NFCT_ERROR_FRAMEDELAYTIMEOUT_MASK;
        if (err_status)
        {
            NRFX_LOG_DEBUG("Error (0x%x)", (unsigned int) err_status);
        }

        /* Clear error status. */
        nrf_nfct_error_status_clear(NRFX_NFCT_ERROR_STATUS_ALL_MASK);
    }

    if (NRFX_NFCT_EVT_ACTIVE(TXFRAMESTART))
    {
        nrf_nfct_event_clear(NRF_NFCT_EVENT_TXFRAMESTART);

        if (m_nfct_cb.config.cb != NULL)
        {
            nrfx_nfct_evt_t nfct_evt;

            nfct_evt.evt_id                                 = NRFX_NFCT_EVT_TX_FRAMESTART;
            nfct_evt.params.tx_framestart.tx_data.p_data    = nrf_nfct_rxtx_buffer_get();
            nfct_evt.params.tx_framestart.tx_data.data_size = NRFX_NFCT_BITS_TO_BYTES(nrf_nfct_tx_bits_get());

            m_nfct_cb.config.cb(&nfct_evt);
        }
    }
}

#endif // NRFX_CHECK(NRFX_NFCT_ENABLED)

Fullscreen nfc.c Download

#include "nfc.h"
#include "TimeScreen.h"
#include "VersionScreen.h"
#include <nrfx_nfct.h>
uint32 nfc_on_count = 0;
uint32 nfc_off_count = 0;
uint32 nfc_update_count = 0;

static uint8_t m_ndef_msg_buf[1024] = {0};      /**< Buffer for NDEF file. */
static uint8_t m_ndef_msg_len;                      /**< Length of the NDEF message. */
extern void bmp_data_evt(void);
extern void nfc_reset_evt(void);
static void nfc_callback(void          * context,
                         nfc_t4t_event_t event,
                         const uint8_t * data,
                         size_t          dataLength,
                         uint32_t        flags)
{
    (void)context;

    switch (event)
    {
        case NFC_T4T_EVENT_FIELD_ON:
			nfc_on_count++;
					NRF_LOG_INFO("NFC_T4T_EVENT_FIELD_ON.");
            //bsp_board_led_on(BSP_BOARD_LED_0);
            break;

        case NFC_T4T_EVENT_FIELD_OFF:
			nfc_off_count++;
					NRF_LOG_INFO("NFC_T4T_EVENT_FIELD_OFF.");
            //bsp_board_leds_off();
            break;

        case NFC_T4T_EVENT_NDEF_READ:
					NRF_LOG_INFO("NFC_T4T_EVENT_NDEF_READ.");
            //bsp_board_led_on(BSP_BOARD_LED_3);
            break;

        case NFC_T4T_EVENT_NDEF_UPDATED:
			nfc_update_count++;
			if(nfc_update_count>=100)
			{
				nfc_reset_evt();
			}
					NRF_LOG_INFO("NFC_T4T_EVENT_NDEF_UPDATED.%x%x%x",data[0],data[1],data[2]);
           // if (dataLength > 0)
            {
			ret_code_t err_code;
				//NRF_LOG_HEXDUMP_INFO(data, dataLength);
			m_ndef_msg_len = dataLength;
			if(data[1] == 0xff)
			{
				set_standby();
			}
			else if(data[1] == 0x00)
			{
				out_standby();
			}
			//Set_bmp_index(data[1]);
			bmp_data_evt();
            }
            break;

        default:
            break;
    }
}
uint8 nfc_id[7] = {0};
void init_nfc_t4t(uint8_t* mac)
{
	ret_code_t err_code;

	/* Set up NFC */
	err_code = nfc_t4t_setup(nfc_callback, NULL);
	APP_ERROR_CHECK(err_code);

	/* Run Read-Write mode for Type 4 Tag platform */
	err_code = nfc_t4t_ndef_rwpayload_set(m_ndef_msg_buf, sizeof(m_ndef_msg_buf));
	APP_ERROR_CHECK(err_code);

	NRF_LOG_INFO("Writable NDEF message example started.");

	
	memcpy(nfc_id,mac,6);
	nfc_t4t_parameter_set(NFC_T4T_PARAM_NFCID1,nfc_id,7);

	/* Start sensing NFC field */
	err_code = nfc_t4t_emulation_start();
	APP_ERROR_CHECK(err_code);
}


/**
 * @brief Callback function for handling NFC events.
 */

[Jørgen Holmefjord]

Hi,

I had a chat with our NFC developers, and they have not seen severe issues like this with the NFCT peripheral.

You should not call nrfx_nfct_state_force(NRFX_NFCT_STATE_ACTIVATED); , this should be used be handled by the driver/library itself when needed.

Our developers could have a look at your issue if you can manage to reproduce it on our DK (and you can provide us with the application and instructions), but it is not much we can do if we can't reproduce on our HW.

Best regards,
Jørgen

[liangzh]

Hi，

I discovered a phenomenon during the verification process where running the example writable_cdef_msg on SDK 17.0.2 resulted in an NFC exception.

Example：examples\nfc\writable_ndef_msg
The process of reproducing:
1. Place the NFC card reader above the NFC coil.
2. Reset the DK board.

When using SDK 17.1.0, it will not appear. Can you help confirm which bug has been fixed?

Best regards,
Liangzh

[Jørgen Holmefjord]

Hi,

Can you elaborate on the exception your are seeing? Is there any log messages or errors reported?

There is one fix in nrfx libraries related to NFCT in the version update between nRF5 SDK v17.0.2 (nrfx v1.8.6) and nRF5 SDK v17.1.0 (nrfx v1.9.0):

• Fixed a race condition in the NFCT driver when starting the transfer.

This might be related to the behavior you are describing.

Best regards,
Jørgen