Configuring Peer Manager for Bonding

I'm attempting to add the bonding components from the ble_app_hids_keyboard example to the ble_app_uart example. I've gotten everything configured to the point where I can connect normally and send data, but when I attempt to initiate a bond the peer manager kicks back an event saying that pairing is not supported (0x85). I can't figure out where this is coming from - the sdk_config files are nearly identical at this point, and I can't find anything in the hids_keyboard example that sets the security config params that's not also included in my uart file. The peer manager even recognizes and stores the ID, it just doesn't want to bond.

My uart main.c:

main.c
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/** @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.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_gpio.h"
#include "nrf_delay.h"
#include "nfc_CR95HF.h"

#include "RFid Click.h"


#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"


#include "nrf_fstorage.h"
#include "fds.h"
#include "peer_manager.h"
#include "ble_conn_state.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                18000                                       /**< 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(20000, 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(10000)                      /**< 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. */
                                        /**< Number of attempts before giving up the connection parameter negotiation. */

#define SEC_PARAM_BOND                      1                                          /**< Perform bonding. */
#define SEC_PARAM_MITM                      0                                          /**< Man In The Middle protection not required. */
#define SEC_PARAM_LESC                      0                                          /**< LE Secure Connections not enabled. */
#define SEC_PARAM_KEYPRESS                  0                                          /**< Keypress notifications not enabled. */
#define SEC_PARAM_IO_CAPABILITIES           BLE_GAP_IO_CAPS_NONE                       /**< No I/O capabilities. */
#define SEC_PARAM_OOB                       0                                          /**< Out Of Band data not available. */
#define SEC_PARAM_MIN_KEY_SIZE              7                                          /**< Minimum encryption key size. */
#define SEC_PARAM_MAX_KEY_SIZE              16     

extern char UID_Buff[8];
extern char ID[38];


APP_TIMER_DEF(m_timestamp_timer);


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}
};
static bool g_uart_linkup                = false;                                   // NFC UART link connection state

static pm_peer_id_t      m_peer_id;                                 /**< Device reference handle to the current bonded central. */
static uint32_t          m_whitelist_peer_cnt;
static pm_peer_id_t      m_whitelist_peers[BLE_GAP_WHITELIST_ADDR_MAX_COUNT]; 




// BEGIN Peer manager functions

static void peer_list_get(pm_peer_id_t * p_peers, uint32_t * p_size)
{
    pm_peer_id_t peer_id;
    uint32_t     peers_to_copy;

    peers_to_copy = (*p_size < BLE_GAP_WHITELIST_ADDR_MAX_COUNT) ?
                     *p_size : BLE_GAP_WHITELIST_ADDR_MAX_COUNT;

    peer_id = pm_next_peer_id_get(PM_PEER_ID_INVALID);
    *p_size = 0;

    while ((peer_id != PM_PEER_ID_INVALID) && (peers_to_copy--))
    {
        p_peers[(*p_size)++] = peer_id;
        peer_id = pm_next_peer_id_get(peer_id);
    }
}


/**@brief Clear bond information from persistent storage.
 */
static void delete_bonds(void)
{
    ret_code_t err_code;

    NRF_LOG_INFO("Erase bonds!");

    err_code = pm_peers_delete();
    APP_ERROR_CHECK(err_code);
}


static void pm_evt_handler(pm_evt_t const * p_evt)
{
    ret_code_t err_code;

    switch (p_evt->evt_id)
    {
        case PM_EVT_BONDED_PEER_CONNECTED:
        {
            NRF_LOG_INFO("Connected to a previously bonded device.");
        } break;

        case PM_EVT_CONN_SEC_SUCCEEDED:
        {
            NRF_LOG_INFO("Connection secured: role: %d, conn_handle: 0x%x, procedure: %d.",
                         ble_conn_state_role(p_evt->conn_handle),
                         p_evt->conn_handle,
                         p_evt->params.conn_sec_succeeded.procedure);

            m_peer_id = p_evt->peer_id;
        } break;

        case PM_EVT_CONN_SEC_FAILED:
        {
            /* Often, when securing fails, it shouldn't be restarted, for security reasons.
             * Other times, it can be restarted directly.
             * Sometimes it can be restarted, but only after changing some Security Parameters.
             * Sometimes, it cannot be restarted until the link is disconnected and reconnected.
             * Sometimes it is impossible, to secure the link, or the peer device does not support it.
             * How to handle this error is highly application dependent. */
             NRF_LOG_WARNING("Failed to secure");
        } break;

        case PM_EVT_CONN_SEC_CONFIG_REQ:
        {
            // Reject pairing request from an already bonded peer.
            pm_conn_sec_config_t conn_sec_config = {.allow_repairing = false};
            pm_conn_sec_config_reply(p_evt->conn_handle, &conn_sec_config);
        } break;

        case PM_EVT_STORAGE_FULL:
        {
            // Run garbage collection on the flash.
            err_code = fds_gc();
            if (err_code == FDS_ERR_NO_SPACE_IN_QUEUES)
            {
                // Retry.
            }
            else
            {
                APP_ERROR_CHECK(err_code);
            }
        } break;

        case PM_EVT_PEERS_DELETE_SUCCEEDED:
        {
            // advertising_start(false);
        } break;

        case PM_EVT_PEER_DATA_UPDATE_SUCCEEDED:
        {
            if (     p_evt->params.peer_data_update_succeeded.flash_changed
                 && (p_evt->params.peer_data_update_succeeded.data_id == PM_PEER_DATA_ID_BONDING))
            {
                NRF_LOG_INFO("New Bond, add the peer to the whitelist if possible");
                NRF_LOG_INFO("\tm_whitelist_peer_cnt %d, MAX_PEERS_WLIST %d",
                               m_whitelist_peer_cnt + 1,
                               BLE_GAP_WHITELIST_ADDR_MAX_COUNT);
                // Note: You should check on what kind of white list policy your application should use.

                if (m_whitelist_peer_cnt < BLE_GAP_WHITELIST_ADDR_MAX_COUNT)
                {
                    // Bonded to a new peer, add it to the whitelist.
                    m_whitelist_peers[m_whitelist_peer_cnt++] = m_peer_id;

                    // The whitelist has been modified, update it in the Peer Manager.
                    err_code = pm_device_identities_list_set(m_whitelist_peers, m_whitelist_peer_cnt);
                    if (err_code != NRF_ERROR_NOT_SUPPORTED)
                    {
                        APP_ERROR_CHECK(err_code);
                    }

                    err_code = pm_whitelist_set(m_whitelist_peers, m_whitelist_peer_cnt);
                    APP_ERROR_CHECK(err_code);
                }
            }
        } break;

        case PM_EVT_PEER_DATA_UPDATE_FAILED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.peer_data_update_failed.error);
        } break;

        case PM_EVT_PEER_DELETE_FAILED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.peer_delete_failed.error);
        } break;

        case PM_EVT_PEERS_DELETE_FAILED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.peers_delete_failed_evt.error);
        } break;

        case PM_EVT_ERROR_UNEXPECTED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.error_unexpected.error);
        } break;

        case PM_EVT_CONN_SEC_START:
        case PM_EVT_PEER_DELETE_SUCCEEDED:
        case PM_EVT_LOCAL_DB_CACHE_APPLIED:
        case PM_EVT_LOCAL_DB_CACHE_APPLY_FAILED:
            // This can happen when the local DB has changed.
        case PM_EVT_SERVICE_CHANGED_IND_SENT:
        case PM_EVT_SERVICE_CHANGED_IND_CONFIRMED:
        default:
            NRF_LOG_DEBUG("Unhandled PM event 0x%02X",p_evt->evt_id )
            break;
    }
}

static void peer_manager_init(void)
{
    ble_gap_sec_params_t sec_param;
    ret_code_t           err_code;

    err_code = pm_init();
    APP_ERROR_CHECK(err_code);

    memset(&sec_param, 0, sizeof(ble_gap_sec_params_t));

    // Security parameters to be used for all security procedures.
    sec_param.bond           = SEC_PARAM_BOND;
    sec_param.mitm           = SEC_PARAM_MITM;
    sec_param.lesc           = SEC_PARAM_LESC;
    sec_param.keypress       = SEC_PARAM_KEYPRESS;
    sec_param.io_caps        = SEC_PARAM_IO_CAPABILITIES;
    sec_param.oob            = SEC_PARAM_OOB;
    sec_param.min_key_size   = SEC_PARAM_MIN_KEY_SIZE;
    sec_param.max_key_size   = SEC_PARAM_MAX_KEY_SIZE;
    sec_param.kdist_own.enc  = 1;
    sec_param.kdist_own.id   = 1;
    sec_param.kdist_peer.enc = 1;
    sec_param.kdist_peer.id  = 1;

    err_code = pm_sec_params_set(&sec_param);
    APP_ERROR_CHECK(err_code);

    err_code = pm_register(pm_evt_handler);
    APP_ERROR_CHECK(err_code);
}


static void ble_advertising_error_handler(uint32_t nrf_error)
{
    APP_ERROR_HANDLER(nrf_error);
}


// END Peer manager functions




/**@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)
{
    NRF_LOG_WARNING("Assert Called");
    NRF_LOG_FINAL_FLUSH();
    app_error_handler(DEAD_BEEF, line_num, p_file_name);
}

/**@brief Timestamp timer timeout handler stub
 */
static void timestamp_timeout_handler(void * p_context)
{
    // NRF_LOG_DEBUG("1s delay");
    
}


/**@brief Selects interface mode and powers up the NFC reader
 *        This doesn't CONFIGURE the reader - just does the work required for
 *        the UART to work correctly
 */
static void nfc_init(void)
{
    g_uart_linkup = false;
    nrf_delay_us(200);
    nrf_gpio_cfg_output(INTERFACEPIN);
    nrf_gpio_pin_clear(INTERFACEPIN); 
    nrf_gpio_cfg_output(NFC_IRQ_IN);
    nrf_gpio_pin_clear(NFC_IRQ_IN);
    nrf_delay_us(520);

    // if you don't reset the pin config, the UART init fails
    nrf_gpio_cfg_default(NFC_IRQ_IN);
    //nrf_delay_ms(10);
    

}

static void null_handler(void * pcontext)
{
}


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

    // Create Timer
    err_code = app_timer_create(&m_timestamp_timer,
                                    APP_TIMER_MODE_REPEATED,
                                    timestamp_timeout_handler);

    APP_ERROR_CHECK(err_code);

    // Starts the "low frequency" clock, with an interrupt every 1000ms
    err_code = app_timer_start(m_timestamp_timer, APP_TIMER_TICKS(1000), NULL);
    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)
{
    NRF_LOG_ERROR("Queued Write Module Error");
    NRF_LOG_FLUSH();
    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)
{

    // TODO: Needs to be replaced. We never want to forward information to the 
    //       NFC reader
    return; // Do Nothing
    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);
    // NUS is "Nordic Uart Service"
}


/**@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;
    NRF_LOG_DEBUG("conn params event");
    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);
        NRF_LOG_DEBUG("on_conn_parms_evt failure");
    }
}


/**@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)
{
    NRF_LOG_ERROR("conn params error handler");
    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);
}


/**@brief Function for putting the chip into sleep mode.
 *
 * @note This function will not return.
 */
static void sleep_mode_enter(void)
{
    NRF_LOG_DEBUG("Entering Sleep Mode");
    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);

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


/**@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_DIRECTED_HIGH_DUTY:
            NRF_LOG_INFO("High Duty Directed advertising.");
            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING_DIRECTED);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_ADV_EVT_DIRECTED:
            NRF_LOG_INFO("Directed advertising.");
            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING_DIRECTED);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_ADV_EVT_FAST:
            NRF_LOG_INFO("Fast advertising.");
            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_ADV_EVT_SLOW:
            NRF_LOG_INFO("Slow advertising.");
            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING_SLOW);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_ADV_EVT_FAST_WHITELIST:
            NRF_LOG_INFO("Fast advertising with whitelist.");
            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING_WHITELIST);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_ADV_EVT_SLOW_WHITELIST:
            NRF_LOG_INFO("Slow advertising with whitelist.");
            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING_WHITELIST);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_ADV_EVT_IDLE:
            NRF_LOG_INFO("Could sleep, don't.");
            // sleep_mode_enter();
            break;

        case BLE_ADV_EVT_WHITELIST_REQUEST:
        {
            ble_gap_addr_t whitelist_addrs[BLE_GAP_WHITELIST_ADDR_MAX_COUNT];
            ble_gap_irk_t  whitelist_irks[BLE_GAP_WHITELIST_ADDR_MAX_COUNT];
            uint32_t       addr_cnt = BLE_GAP_WHITELIST_ADDR_MAX_COUNT;
            uint32_t       irk_cnt  = BLE_GAP_WHITELIST_ADDR_MAX_COUNT;

            err_code = pm_whitelist_get(whitelist_addrs, &addr_cnt,
                                        whitelist_irks,  &irk_cnt);
            APP_ERROR_CHECK(err_code);
            NRF_LOG_DEBUG("pm_whitelist_get returns %d addr in whitelist and %d irk whitelist",
                          addr_cnt, irk_cnt);

            // Apply the whitelist.
            err_code = ble_advertising_whitelist_reply(&m_advertising,
                                                       whitelist_addrs,
                                                       addr_cnt,
                                                       whitelist_irks,
                                                       irk_cnt);
            APP_ERROR_CHECK(err_code);
        } break; //BLE_ADV_EVT_WHITELIST_REQUEST

        case BLE_ADV_EVT_PEER_ADDR_REQUEST:
        {
            pm_peer_data_bonding_t peer_bonding_data;

            // Only Give peer address if we have a handle to the bonded peer.
            if (m_peer_id != PM_PEER_ID_INVALID)
            {
                err_code = pm_peer_data_bonding_load(m_peer_id, &peer_bonding_data);
                if (err_code != NRF_ERROR_NOT_FOUND)
                {
                    APP_ERROR_CHECK(err_code);

                    ble_gap_addr_t * p_peer_addr = &(peer_bonding_data.peer_ble_id.id_addr_info);
                    err_code = ble_advertising_peer_addr_reply(&m_advertising, p_peer_addr);
                    APP_ERROR_CHECK(err_code);
                }
            }
        } break; //BLE_ADV_EVT_PEER_ADDR_REQUEST

        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;
    //NRF_LOG_DEBUG("ble event: 0x%X", p_ble_evt->header.evt_id);

    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");
            // LED indication will be changed when advertising starts.
            m_conn_handle = BLE_CONN_HANDLE_INVALID;
            NRF_LOG_DEBUG("Disconnect code 0x%X", p_ble_evt->evt.gap_evt.params.disconnected.reason);

            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:
            // TODO this is dying when trying to bond. Says "invalid state"
            break;
            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);
            NRF_LOG_DEBUG("Got BLE_GAP_EVT_SEC_PARAMS_REQUEST event.");
            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.
            NRF_LOG_DEBUG("GATT Client Timeout.");
            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.
            NRF_LOG_DEBUG("GATT Server Timeout.");
            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;
        case BLE_GAP_EVT_AUTH_STATUS:
            NRF_LOG_DEBUG("BLE_GAP_EVT_AUTH_STATUS event.");
            // p_ble_evt->header.evt_len;
            NRF_LOG_DEBUG("Pairing auth status: 0x%02X", \
                p_ble_evt->evt.gap_evt.params.auth_status.auth_status );
            NRF_LOG_DEBUG("Pairing error source: 0x%02X", \
                p_ble_evt->evt.gap_evt.params.auth_status.error_src);

       // case BLE_GAP_EVT_DATA_LENGTH_UPDATE
        default:
            // Unknown event. 
            NRF_LOG_INFO("Unhandled event in ble_evt_handler");
            NRF_LOG_INFO("Event ID 0x%X", p_ble_evt->header.evt_id);

            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 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;  // Static variables instantiated at compile time - index isn't reset per call
    uint32_t       err_code;

    switch (p_event->evt_type)
    {
        NRF_LOG_DEBUG("UART Event type 0x%X", p_event->evt_type);
        case APP_UART_DATA_READY:
            // Don't handle this event - we're going to block instead
            return;
            
            UNUSED_VARIABLE(app_uart_get(&data_array[index]));
            index++;


            // Got byte, byte is on buffer. 
            // This would be easier to read as a switch?
            // NRF_LOG_DEBUG("Got Byte 0x%X", data_array[index-1]);
            if (data_array[0] == NFC_ECHO)
            {
                g_uart_linkup = true;
                index = 0;
                NRF_LOG_DEBUG("Recieved NFC_ECHO");
            }
            else if (index > 1)
            {
                // Have at least a command and a length. 
                if (data_array[1] <= NFC_DATA_MAXLEN && data_array[1] + 2 == index)
                {
                   // NRF_LOG_DEBUG("Complete command received");
                    NRF_LOG_DEBUG("Response 0x%X in buffer. Total %d bytes in buffer", data_array[0], index);

                    index = 0;
                    // NRF_LOG_FLUSH();
                }
            }

            // This handles forwarding data to DCU
            else if ((data_array[index - 1] == '\n') || (index >= (m_ble_nus_max_data_len)))
            {
                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_BUSY) &&
                         (err_code != NRF_ERROR_NOT_FOUND) )
                    {
                        APP_ERROR_CHECK(err_code);
                    }
                } while (err_code == NRF_ERROR_BUSY);

                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    = NFC_UART_RX,
        .tx_pin_no    = NFC_UART_TX,
        .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_57600
#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.include_appearance = false;
  //  init.advdata.flags              = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;

    init.advdata.flags              = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_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_whitelist_enabled          = true;
    init.config.ble_adv_directed_high_duty_enabled = true;
    init.config.ble_adv_directed_enabled           = false;
    init.config.ble_adv_directed_interval          = 0;
    init.config.ble_adv_directed_timeout           = 0;
    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.config.ble_adv_slow_enabled               = true;
    init.config.ble_adv_slow_interval              = APP_ADV_INTERVAL;
    init.config.ble_adv_slow_timeout               = APP_ADV_DURATION;
 

    init.evt_handler = on_adv_evt;
    init.error_handler = ble_advertising_error_handler;

    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);
}


static uint32_t timestamp_func(void)
{
    return app_timer_cnt_get();
}

/**@brief Function for initializing the nrf log module.
 */
static void log_init(void)
{
    ret_code_t err_code = NRF_LOG_INIT(timestamp_func);
    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)
{
    UNUSED_RETURN_VALUE(NRF_LOG_PROCESS());
    uint32_t err_code;
    uint16_t length = strlen(ID);
    if(ID[0] != 0)
    {
        do
        {
            NRF_LOG_DEBUG("UID: %s",ID);
            while(NRF_LOG_PROCESS());
            
            err_code = ble_nus_data_send(&m_nus, ID, &length, m_conn_handle);
            if ( (err_code != NRF_ERROR_INVALID_STATE) && (err_code != NRF_ERROR_BUSY) &&
                 (err_code != NRF_ERROR_NOT_FOUND) )
            {
                APP_ERROR_CHECK(err_code);
            }
        } while (err_code == NRF_ERROR_BUSY);
            UID_Buff[0] = 0;
            ID[0] = 0;
    }

    #ifndef  DEBUG
    nrf_pwr_mgmt_run();
    #endif
}


/**@brief Function for starting advertising.
 */
static void advertising_start(void)
{
     if (false)
    {
        delete_bonds();
        // Advertising is started by PM_EVT_PEERS_DELETE_SUCCEEDED event.
    }
    else
    {
        ret_code_t ret;

        memset(m_whitelist_peers, PM_PEER_ID_INVALID, sizeof(m_whitelist_peers));
        m_whitelist_peer_cnt = (sizeof(m_whitelist_peers) / sizeof(pm_peer_id_t));

        peer_list_get(m_whitelist_peers, &m_whitelist_peer_cnt);

        ret = pm_whitelist_set(m_whitelist_peers, m_whitelist_peer_cnt);
        APP_ERROR_CHECK(ret);

        // Setup the device identies list.
        // Some SoftDevices do not support this feature.
        ret = pm_device_identities_list_set(m_whitelist_peers, m_whitelist_peer_cnt);
        if (ret != NRF_ERROR_NOT_SUPPORTED)
        {
            APP_ERROR_CHECK(ret);
        }

        ret = ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
        APP_ERROR_CHECK(ret);
    }
}


/**@brief Application main function.
 */
int main(void)
{
    bool erase_bonds;


    timers_init();
    log_init();
    NRF_LOG_DEBUG("Starting Logging");

    nfc_init();
    uart_init();
 
    power_management_init();
    ble_stack_init();
    gap_params_init();
    gatt_init();
    services_init();
    advertising_init();
    conn_params_init();

    peer_manager_init();.
    advertising_start();
   
    rfid_main();

    for (;;)
    {
        idle_state_handle();
        nfc_main_loop_once();
    }
}


/**
 * @}
 */

On line 779 there's a call to sd_ble_gap_sec_params_reply which should be commented out - I was just experimenting with it and uploaded the wrong version. That call will cause an softdevice assert, I guess because the peer_manager or security manager already dealt with it.