Hello, I have developed an application that advertises, connects, pairs/bonds using SEC_JUST_WORKS configuration, and then transmits data at ~2 second intervals to a smartphone application. The application works perfectly fine with a custom built mobile app that was developed using Flutter and the flutter_blue library. The application works flawlessly on both android and iOS. However, when I try to connect to the device with nRF Connect or Adafruit's Bluefruit LE Connect, calling ble_nus_data_send and checking the error code with APP_ERROR_CHECK throws error code 0x8 which is a fatal error.
The strange part is that if I remove the call to APP_ERROR_CHECK, the application behaves as expected and streams data to any mobile application with no problem, including nRF Connect and Bluefruit LE Connect. To summarize, our custom mobile application works with or without calling APP_ERROR_CHECK (line 927 below), whereas the nRF52 DK will crash if APP_ERROR_CHECK is called when connecting to nRF Connect or Bluefruit LE. All applications work fine when the error check is commented out and the nRF52 DK does not report any error.
I am aware that this error can be caused due to lack of connection or calling ble_nus_data_send during an ongoing MTU exchange. However, the flow of my application is as follows:
1. Advertise
2. Upon connection initiated by the phone, the peer manager handler pm_evt_handler is entered
3. Case PM_EVT_BONDED_PEER_CONNECTED is entered wthin pm_evt_handler
4. gatt_evt_handler is entered, MTU is updated
5. From within gatt_evt_handler, I begin an app timer in which the callback function begins reading data from SAADC
6. saadc_callback is entered and various data is read
7. From within saadc_callback, I call ble_nus_data_send with the appropriate data packed into a char array
8. If ble_nus_data_send is successful, I disable the SAADC and restart my timer
9. Steps 6 through 8 are repeated until connection is broken
I have debug logs in all my event handlers, to confirm that my bonding is successful and that connection is successful following the above application flow. Below is my debug logs I receive when fatal error 0x8 is thrown:
<info> app: ENTERED PM_EVT_HANDLER <info> app: ENTERED PM_EVT_HANDLER <info> app: PM_EVT_BONDED_PEER_CONNECTED <info> app: ENTERED PM_EVT_HANDLER <info> app: CONNECTION MADE (ble_gap_evt) <info> app: ENTERED PM_EVT_HANDLER <info> app: ENTERED PM_EVT_HANDLER <info> app: ENTERED PM_EVT_HANDLER <info> peer_manager_handler: Connection secured: role: Peripheral, conn_handle: 0, procedure: Encryption <info> app: ENTERED PM_EVT_HANDLER <info> app: PM_EVT_CONN_SEC_SUCCEEDED <info> app: Data len is set to 0xB6(182) <info> app: TIMER STARTED (gatt_evt_handler) <info> app: Setting saadc input to AIN1 <info> app: read pH val, restarting: 372 <info> app: Setting saadc input to AIN3 <info> app: read batt val, restarting: 2928 <info> app: Setting saadc input to AIN0 <info> app: read temp val: 526 <error> app: Fatal error
My intuition says that even though my event handlers report connection, there still may be some process or MTU exchange ocurring in the background. Is there a more appropriate place to start my app timer which causes my SAADC readings and bluetooth transmission to start? I am not sure what the nRF Connect mobile application is doing that our custom Flutter application is not doing. It is also strange to me that even though an error is apparently being thrown when nRF Connect or Bluefruit LE Connect are used, if I don't check it the mobile device can receive the packets/data with no problem. My main.c and sdk_config.h are provided below, any suggestions would be greatly appreciated!
I am using Segger Embedded Studios and SDK V 15.2.0.
main.c
/**
* Copyright (c) 2014 - 2018, 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.
*
*/
/** @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 "boards.h"
#include "nrf.h"
#include "nrf_sdh.h"
#include "nrf_sdh_soc.h"
#include "nrf_sdh_ble.h"
#include "nrf_ble_qwr.h"
#include "nrf_pwr_mgmt.h"
#include "nrf_ble_gatt.h"
#include "nrf_saadc.h"
#include "nrf_drv_clock.h"
#include "nrf_delay.h"
#include "nrf_drv_gpiote.h"
#include "nrf_drv_saadc.h"
#include "nrf_drv_ppi.h"
#include "nrf_drv_timer.h"
#include "nrfx_ppi.h"
#include "nrfx_pwm.h"
#include "nrf_timer.h"
#include "nrfx_saadc.h"
#include "ble_nus.h"
#include "ble_hci.h"
#include "ble_advdata.h"
#include "ble_advertising.h"
#include "ble_conn_params.h"
#include "app_timer.h"
#include "app_uart.h"
#include "app_util_platform.h"
#include "app_fifo.h"
#include "app_pwm.h"
#include "app_error.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
// Included for peer manager
#include "nrf_fstorage.h"
#include "nrf_fstorage_sd.h"
#include "fds.h"
#include "peer_manager.h"
#include "peer_manager_handler.h"
#include "ble_conn_state.h"
#if defined (UART_PRESENT)
#include "nrf_uart.h"
#endif
#if defined (UARTE_PRESENT)
#include "nrf_uarte.h"
#endif
#define APP_BLE_CONN_CFG_TAG 1 /**< A tag identifying the SoftDevice BLE configuration. */
#define DEVICE_NAME "Lura_Health" /**< 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 510 /**< 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(200, UNIT_1_25_MS) /**< Maximum acceptable connection interval (200 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. */
#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 /**< Maximum encryption key size. */
#define SAMPLES_IN_BUFFER 11 /**< SAADC buffer > */
#define NRF_SAADC_CUSTOM_CHANNEL_CONFIG_SE(PIN_P) \
{ \
.resistor_p = NRF_SAADC_RESISTOR_DISABLED, \
.resistor_n = NRF_SAADC_RESISTOR_DISABLED, \
.gain = NRF_SAADC_GAIN1_5, \
.reference = NRF_SAADC_REFERENCE_INTERNAL, \
.acq_time = NRF_SAADC_ACQTIME_10US, \
.mode = NRF_SAADC_MODE_SINGLE_ENDED, \
.burst = NRF_SAADC_BURST_DISABLED, \
.pin_p = (nrf_saadc_input_t)(PIN_P), \
.pin_n = NRF_SAADC_INPUT_DISABLED \
}
/* UNDEFS FOR DEBUGGING */
#undef RX_PIN_NUMBER
#undef RTS_PIN_NUMBER
#undef LED_4
#undef LED_STOP
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. */
APP_TIMER_DEF(m_timer_id);
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}
};
/* Lura Health nRF52810 port assignments */
#define ENABLE_ANALOG_PIN 4
/* GLOBALS */
uint32_t AVG_PH_VAL = 0;
uint32_t AVG_BATT_VAL = 0;
uint32_t AVG_TEMP_VAL = 0;
bool PH_IS_READ = false;
bool BATTERY_IS_READ = false;
bool SAADC_CALIBRATED = false;
bool CONNECTION_MADE = false;
static const nrf_drv_timer_t m_timer = NRF_DRV_TIMER_INSTANCE(1);
static nrf_saadc_value_t m_buffer_pool[1][SAMPLES_IN_BUFFER];
static nrf_ppi_channel_t m_ppi_channel;
// Forward declarations
static inline void enable_pH_voltage_reading (void);
static inline void enable_switch (void);
static inline void check_reed_switch (void);
static inline void disable_pH_voltage_reading (void);
static inline void saadc_init (void);
static inline void enable_analog_pin (void);
static inline void disable_analog_pin (void);
static void advertising_start (bool erase_bonds);
/**@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 handling Peer Manager events.
*
* @param[in] p_evt Peer Manager event.
*/
static void pm_evt_handler(pm_evt_t const * p_evt)
{
NRF_LOG_INFO("ENTERED PM_EVT_HANDLER");
NRF_LOG_FLUSH();
pm_handler_on_pm_evt(p_evt);
pm_handler_flash_clean(p_evt);
switch (p_evt->evt_id)
{
case PM_EVT_CONN_SEC_SUCCEEDED:
NRF_LOG_INFO("PM_EVT_CONN_SEC_SUCCEEDED");
NRF_LOG_FLUSH();
break;
case PM_EVT_PEERS_DELETE_SUCCEEDED:
NRF_LOG_INFO("PM_EVT_CONN_SEC_SUCCEEDED");
NRF_LOG_FLUSH();
advertising_start(false);
break;
case PM_EVT_BONDED_PEER_CONNECTED:
NRF_LOG_INFO("PM_EVT_BONDED_PEER_CONNECTED");
NRF_LOG_FLUSH();
break;
case PM_EVT_CONN_SEC_CONFIG_REQ:
{
// Allow pairing request from an already bonded peer.
NRF_LOG_INFO("PM_EVT_CONN_SEC_CONFIG_REQ");
NRF_LOG_FLUSH();
pm_conn_sec_config_t conn_sec_config = {.allow_repairing = true};
pm_conn_sec_config_reply(p_evt->conn_handle, &conn_sec_config);
} break;
default:
break;
}
}
/**@brief Function for initializing the timer module.
*/
static inline void timers_init(void)
{
uint32_t err_code;
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 inline 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 inline 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);
}
/**@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;
// Go to system-off mode (function will not return; wakeup causes 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_FAST:
break;
case BLE_ADV_EVT_IDLE:
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:
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);
CONNECTION_MADE = true;
NRF_LOG_INFO("CONNECTION MADE (ble_gap_evt) \n");
break;
case BLE_GAP_EVT_DISCONNECTED:
if(p_ble_evt->evt.gap_evt.params.disconnected.reason ==
BLE_HCI_CONNECTION_TIMEOUT)
{
//disconnect_reason is BLE_HCI_CONNECTION_TIMEOUT
NRF_LOG_INFO("connection timeout\n");
}
// LED indication will be changed when advertising starts.
m_conn_handle = BLE_CONN_HANDLE_INVALID;
CONNECTION_MADE = false;
NRF_LOG_INFO("DISCONNECTED\n");
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_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);
CONNECTION_MADE = false;
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);
CONNECTION_MADE = false;
APP_ERROR_CHECK(err_code);
break;
case BLE_GAP_EVT_AUTH_STATUS:
NRF_LOG_INFO("BLE_GAP_EVT_AUTH_STATUS: status=0x%x bond=0x%x lv4: %d kdist_own:0x%x kdist_peer:0x%x",
p_ble_evt->evt.gap_evt.params.auth_status.auth_status,
p_ble_evt->evt.gap_evt.params.auth_status.bonded,
p_ble_evt->evt.gap_evt.params.auth_status.sm1_levels.lv4,
*((uint8_t *)&p_ble_evt->evt.gap_evt.params.auth_status.kdist_own),
*((uint8_t *)&p_ble_evt->evt.gap_evt.params.auth_status.kdist_peer));
break;
case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
NRF_LOG_INFO("BLE_GAP_EVT_SEC_PARAMS_REQUEST");
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 the 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);
}
/**@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);
}
/**@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.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 the nrf log module.
*/
static void log_init(void)
{
ret_code_t err_code = NRF_LOG_INIT(NULL);
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());
nrf_pwr_mgmt_run();
}
/**@brief Function for starting advertising.
*/
static void advertising_start(bool erase_bonds)
{
if (erase_bonds == true)
{
delete_bonds();
// Advertising is started by PM_EVT_PEERS_DELETED_SUCEEDED event
}
else
{
ret_code_t err_code = ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
APP_ERROR_CHECK(err_code);
}
}
/* This function sets enable pin for ISFET circuitry to HIGH
*/
static inline void enable_analog_circuit(void)
{
nrf_drv_gpiote_out_config_t config = NRFX_GPIOTE_CONFIG_OUT_SIMPLE(false);
if(nrf_drv_gpiote_is_init() == false) {
nrf_drv_gpiote_init();
}
nrf_drv_gpiote_out_init(ENABLE_ANALOG_PIN, &config);
nrf_drv_gpiote_out_set(ENABLE_ANALOG_PIN);
}
/* This function sets enable pin for ISFET circuitry to LOW
*/
static inline void disable_analog_pin(void)
{
// Redundant, but follows design
nrfx_gpiote_uninit();
}
void timer_handler(nrf_timer_event_t event_type, void * p_context)
{
// To Add Later
}
static inline void saadc_sampling_event_init(void)
{
ret_code_t err_code;
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.bit_width = NRF_TIMER_BIT_WIDTH_32;
err_code = nrf_drv_timer_init(&m_timer, &timer_cfg, timer_handler);
APP_ERROR_CHECK(err_code);
/* setup m_timer for compare event every 15us */
uint32_t ticks = nrf_drv_timer_us_to_ticks(&m_timer, 35);
nrf_drv_timer_extended_compare(&m_timer,
NRF_TIMER_CC_CHANNEL0,
ticks,
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
nrf_drv_timer_enable(&m_timer);
uint32_t timer_compare_event_addr =
nrf_drv_timer_compare_event_address_get(&m_timer,
NRF_TIMER_CC_CHANNEL0);
uint32_t saadc_sample_task_addr = nrf_drv_saadc_sample_task_get();
/* setup ppi channel so that timer compare event triggers task in SAADC */
err_code = nrf_drv_ppi_channel_alloc(&m_ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(m_ppi_channel,
timer_compare_event_addr,
saadc_sample_task_addr);
APP_ERROR_CHECK(err_code);
}
static inline void saadc_sampling_event_enable(void)
{
ret_code_t err_code = nrf_drv_ppi_channel_enable(m_ppi_channel);
APP_ERROR_CHECK(err_code);
}
static inline void restart_saadc(void)
{
nrfx_timer_uninit(&m_timer);
nrfx_ppi_channel_free(m_ppi_channel);
nrfx_saadc_uninit();
while(nrfx_saadc_is_busy()) {
// make sure SAADC is not busy
}
enable_pH_voltage_reading();
}
// Pack integer values into byte array to send via bluetooth
void create_bluetooth_packet(uint32_t ph_val,
uint32_t batt_val,
uint32_t temp_val,
uint8_t* total_packet)
{
/*
{0,0,0,0,44, pH value arr[0-3], comma arr[4]
0,0,0,0,44, temperature arr[5-8], comma arr[9]
0,0,0,0,10}; battery value arr[10-13], EOL arr[14]
*/
uint32_t temp = 0; // hold intermediate divisions of variables
uint32_t ASCII_DIG_BASE = 48;
// Pack ph_val into appropriate location
temp = ph_val;
for(int i = 3; i >= 0; i--){
if (i == 3) total_packet[i] = (uint8_t)(temp % 10 + ASCII_DIG_BASE);
else {
temp = temp / 10;
total_packet[i] = (uint8_t)(temp % 10 + ASCII_DIG_BASE);
}
}
// Pack temp_val into appropriate location
temp = temp_val;
for(int i = 8; i >= 5; i--){
if (i == 8) total_packet[i] = (uint8_t)(temp % 10 + ASCII_DIG_BASE);
else {
temp = temp / 10;
total_packet[i] = (uint8_t)(temp % 10 + ASCII_DIG_BASE);
}
}
// Pack batt_val into appropriate location
temp = batt_val;
for(int i = 13; i >= 10; i--){
if (i == 13) total_packet[i] = (uint8_t)(temp % 10 + ASCII_DIG_BASE);
else {
temp = temp / 10;
total_packet[i] = (uint8_t)(temp % 10 + ASCII_DIG_BASE);
}
}
}
static inline uint32_t saadc_result_to_mv(uint32_t saadc_result)
{
float saadc_denom = 4095.0;
float saadc_vref_mv = 3000.0;
float saadc_res_in_mv = ((float)saadc_result/saadc_denom) * saadc_vref_mv;
return (uint32_t)saadc_res_in_mv;
}
/**
* Function is called when SAADC reading event is done. First done event
* reads pH input, stores in global variable. Second reading stores
* pH data, combines pH and temp data into a comma-seperated string,
* then transmits via BLE.
*
* BUG: p_buffer[0] is always '0' when reading pH at high frequency.
* Workaround is to average values besides 1, divide by
* samples_in_buffer -1 .
*/
static inline void saadc_callback(nrf_drv_saadc_evt_t const * p_event)
{
if (p_event->type == NRF_DRV_SAADC_EVT_DONE)
{
ret_code_t err_code;
uint16_t total_size = 15;
uint32_t avg_saadc_reading = 0;
// Byte array to store total packet
uint8_t total_packet[] = {48,48,48,48,44, /* pH value, comma */
48,48,48,48,44, /* Temperature, comma */
48,48,48,48,10}; /* Battery value, EOL */
err_code = nrf_drv_saadc_buffer_convert(p_event->data.done.p_buffer,
SAMPLES_IN_BUFFER);
APP_ERROR_CHECK(err_code);
// Sum and average SAADC values
for (int i = 1; i < SAMPLES_IN_BUFFER; i++)
{
if (p_event->data.done.p_buffer[i] < 0) {
avg_saadc_reading += 0;
}
else {
avg_saadc_reading += p_event->data.done.p_buffer[i];
}
}
avg_saadc_reading = avg_saadc_reading/(SAMPLES_IN_BUFFER - 1);
// If ph has not been read, read it then restart SAADC to read temp
if (!PH_IS_READ) {
AVG_PH_VAL = saadc_result_to_mv(avg_saadc_reading);
PH_IS_READ = true;
// Uninit saadc peripheral, restart saadc, enable sampling event
NRF_LOG_INFO("read pH val, restarting: %d", AVG_PH_VAL);
NRF_LOG_FLUSH();
restart_saadc();
}
// If pH has been read but not battery, read battery then restart
else if (!(PH_IS_READ && BATTERY_IS_READ)) {
AVG_BATT_VAL = saadc_result_to_mv(avg_saadc_reading);
NRF_LOG_INFO("read batt val, restarting: %d", AVG_BATT_VAL);
NRF_LOG_FLUSH();
BATTERY_IS_READ = true;
restart_saadc();
}
// Once temp, batter and ph have been read, create and send data in packet
else {
AVG_TEMP_VAL = saadc_result_to_mv(avg_saadc_reading);
NRF_LOG_INFO("read temp val: %d", AVG_TEMP_VAL);
NRF_LOG_FLUSH();
// Create bluetooth data
create_bluetooth_packet(AVG_PH_VAL, AVG_BATT_VAL,
AVG_TEMP_VAL, total_packet);
// Send data
err_code = ble_nus_data_send(&m_nus, total_packet,
&total_size, m_conn_handle);
APP_ERROR_CHECK(err_code);
// reset global control boolean
PH_IS_READ = false;
BATTERY_IS_READ = false;
// Turn off peripherals
NRF_LOG_INFO("BLUETOOTH DATA SENT\n");
NRF_LOG_FLUSH();
disable_pH_voltage_reading();
NRF_LOG_INFO("SAADC DISABLED\n");
NRF_LOG_FLUSH();
}
}
}
/* Reads pH transducer output
*/
void saadc_init(void)
{
ret_code_t err_code;
nrf_saadc_input_t ANALOG_INPUT;
// Change pin depending on global control boolean
if (!PH_IS_READ) {
NRF_LOG_INFO("Setting saadc input to AIN1\n");
ANALOG_INPUT = NRF_SAADC_INPUT_AIN1;
}
else if (!(PH_IS_READ && BATTERY_IS_READ)) {
NRF_LOG_INFO("Setting saadc input to AIN3\n");
ANALOG_INPUT = NRF_SAADC_INPUT_AIN3;
}
else {
NRF_LOG_INFO("Setting saadc input to AIN0\n");
ANALOG_INPUT = NRF_SAADC_INPUT_AIN0;
}
nrf_saadc_channel_config_t channel_config =
NRF_SAADC_CUSTOM_CHANNEL_CONFIG_SE(ANALOG_INPUT);
err_code = nrf_drv_saadc_init(NULL, saadc_callback);
APP_ERROR_CHECK(err_code);
/*
* BUG: calibration never completes
*/
// Calibrate offset
// if(!SAADC_CALIBRATED) {
// while (nrfx_saadc_calibrate_offset() != NRFX_SUCCESS) {
// NRF_LOG_INFO("calibration does not equal success\n");
// NRF_LOG_FLUSH();
// nrf_delay_us(10);
// }
// SAADC_CALIBRATED = true;
// while (nrfx_saadc_is_busy()) {
// NRF_LOG_INFO("saadc busy while restarting\n");
// NRF_LOG_FLUSH();
// nrf_delay_ms(1000);
// }
// }
err_code = nrf_drv_saadc_channel_init(0, &channel_config);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[0], SAMPLES_IN_BUFFER);
APP_ERROR_CHECK(err_code);
}
/* This function initializes and enables SAADC sampling
*/
static inline void enable_pH_voltage_reading(void)
{
saadc_init();
saadc_sampling_event_init();
saadc_sampling_event_enable();
nrf_pwr_mgmt_run();
}
/* Function unitializes and disables SAADC sampling, restarts 1 second timer
*/
static inline void disable_pH_voltage_reading(void)
{
nrfx_timer_uninit(&m_timer);
nrfx_ppi_channel_free(m_ppi_channel);
nrfx_saadc_uninit();
// *** DISABLE ENABLE ***
disable_analog_pin();
// Restart timer
ret_code_t err_code;
err_code = app_timer_start(m_timer_id, APP_TIMER_TICKS(1500), NULL);
APP_ERROR_CHECK(err_code);
nrf_pwr_mgmt_run();
NRF_LOG_INFO("TIMER RESTARTED (disable_ph_voltage_reading)\n");
NRF_LOG_FLUSH();
}
static inline void single_shot_timer_handler()
{
// disable timer
ret_code_t err_code;
err_code = app_timer_stop(m_timer_id);
// Delay to ensure appropriate timing between
enable_analog_circuit();
// PWM output, ISFET capacitor, etc
nrf_delay_us(2000);
// Begin SAADC initialization/start
enable_pH_voltage_reading();
}
/**@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);
ret_code_t err_code;
// Create application timer
err_code = app_timer_create(&m_timer_id,
APP_TIMER_MODE_SINGLE_SHOT,
single_shot_timer_handler);
APP_ERROR_CHECK(err_code);
// 1 second timer intervals
err_code = app_timer_start(m_timer_id, APP_TIMER_TICKS(2000), NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_INFO("TIMER STARTED (gatt_evt_handler) \n");
NRF_LOG_FLUSH();
}
/**@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 Application main function.
*/
int main(void)
{
bool erase_bonds = false;
log_init();
timers_init();
power_management_init();
ble_stack_init();
gap_params_init();
gatt_init();
services_init();
advertising_init();
conn_params_init();
peer_manager_init();
advertising_start(erase_bonds);
// Enter main loop.
while (true)
{
idle_state_handle();
}
}
/*
* @}
*/
