sd_ble_gatts_value_set not working SDK11

[Pavan kumar]

We are having a project where temperature values will update whenever the temperature changes ,So I'm writing code like this

uint32_t ble_sh35_update_temp(ble_sh35_t *p_sh35, uint32_t temper_value)
{
	uint16_t len = 4;
    ble_gatts_hvx_params_t hvx_params;

    if (p_sh35 == NULL)
    {
        return NRF_ERROR_NULL;
    }

    if ((p_sh35->conn_handle == BLE_CONN_HANDLE_INVALID))
    {
    	 ble_gatts_value_t gatts_value;
    	 memset(&gatts_value, 0, sizeof(gatts_value));

    	 gatts_value.len     = len;
    	 gatts_value.offset  = 0;
    	 gatts_value.p_value = (uint8_t *)temper_value ;

    	 uint32_t err_code = sd_ble_gatts_value_set(p_sh35->conn_handle,p_sh35->temper_handles.value_handle,&gatts_value);
    	 printf("err_code = %d\n",err_code);
    	 
    }

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

    hvx_params.handle = p_sh35->temper_handles.value_handle;
    hvx_params.p_data = (uint8_t *)&temper_value;
    hvx_params.p_len  = &len;
    hvx_params.type   = BLE_GATT_HVX_NOTIFICATION;

    return sd_ble_gatts_hvx(p_sh35->conn_handle, &hvx_params);
}

My intention is if the phone is connected it will notify, if not it update the value so that whenever the app connects it will read the latest reading, But surprisingly it leading to hard fault, its not even printing the error code, I'm not sure what was the problem, can any one please suggest me where I went wrong,

Thanks in advance.

[Jørgen Holmefjord]

Have you tried debugging to see which error code the applications is failing on? You should add a check if notifications is enabled and only send notification if it is. Calling sd_ble_gatts_hvx() when notifications is not enabled, will result in a NRF_ERROR_INVALID_STATE error. You can take a look at how this is handled in the ble_app_uart example in the SDK. Hint: take a look at the functions ble_nus_string_send() and on_write() ins ble_nus.c.