"Pairing rejected by Nordic_HRM"

[Priyajit]

While I am going to pair with my android 9 Asus mobile phone with SDK 17 nRF52840. It in my mobile showing "Pairing rejected by Nordic_HRM". After that  I have added a some code line to

static void peer_manager_init(bool erase_bonds);

sec_param.bond = false;

sec_param.mitm = false;

sec_param.lesc = 0;

sec_param.keypress = 0;

sec_param.io_caps = BLE_GAP_IO_CAPS_NONE;

sec_param.oob = false;

sec_param.min_key_size = 7;

sec_param.max_key_size = 16;

sec_param.kdist_own.enc = 0;

sec_param.kdist_own.id = 0;

sec_param.kdist_peer.enc = 0;

sec_param.kdist_peer.id = 0;

And getting same "Pairing rejected by Nordic_HRM"

After that I have added this code,

sec_param.bond = true;
sec_param.mitm = false;
sec_param.lesc = 0;
sec_param.keypress = 0;
sec_param.io_caps = BLE_GAP_IO_CAPS_NONE;
sec_param.oob = false;
sec_param.min_key_size = 7;
sec_param.max_key_size = 16;
sec_param.kdist_own.enc = 1;
sec_param.kdist_own.id = 1;
sec_param.kdist_peer.enc = 1;
sec_param.kdist_peer.id = 1;

And getting same "Pairing rejected by Nordic_HRM"

Please give some solution.

[Simonr]

Hi

Setting sec_param.bond = false; as you've done in the first snippet will cause this "pairing rejected" message as well, as this will disable the bonding feature. I would suggest leaving the parameters as they are by default in the ble_app_hrs example project (see snippet below).

// Defines used to initialize the peer manager

#define SEC_PARAM_BOND                      1                                       /**< Perform bonding. */
#define SEC_PARAM_MITM                      0                                       /**< Man In The Middle protection not required. */
#define SEC_PARAM_LESC                      1                                       /**< LE Secure Connections 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                                      /**< Maximum encryption key size. */

// peer manager initialization

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);
}

Did you have any luck erasing the bonding information on the nRF side, as that was the only way I was able to reproduce the "Pairing rejected by Nordic_HRM" message here on my side.

Best regards,

Simon

[Priyajit]

Yes, it is working. But I observed if I forget the "Nordic_HRM" from paired device on my Asus mobile end, then until I clear memory of nordic devices, I can not again paired nordic device again. How can I again pair again the nodic devices with my same mobile without clear Nordic memory. Please help.