Implementation of Heart Rate Service on nRF52-DK with security (bonding/pairing procedure). Correct key for smartphone to enter is printed on serial. Baud rate 9600, 8 bits + 1 stop bit + no parity bit.

Fork of mbed-os-example-ble-HeartRate by mbed-os-examples

source/main.cpp

Committer:
mbed_official
Date:
2016-07-28
Revision:
1:72c60abef7e7
Parent:
0:fb66cae3e9a1
Child:
10:ac3615194d04

File content as of revision 1:72c60abef7e7:

/* mbed Microcontroller Library
 * Copyright (c) 2006-2015 ARM Limited
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <mbed-events/events.h>
#include <mbed.h>
#include "ble/BLE.h"
#include "ble/Gap.h"
#include "ble/services/HeartRateService.h"

DigitalOut led1(LED1, 1);

const static char     DEVICE_NAME[] = "HRM";
static const uint16_t uuid16_list[] = {GattService::UUID_HEART_RATE_SERVICE};

static uint8_t hrmCounter = 100; // init HRM to 100bps
static HeartRateService *hrServicePtr;

static EventQueue eventQueue(
    /* event count */ 16 * /* event size */ 32
);

void disconnectionCallback(const Gap::DisconnectionCallbackParams_t *params)
{
    BLE::Instance().gap().startAdvertising(); // restart advertising
}

void updateSensorValue() {
    // Do blocking calls or whatever is necessary for sensor polling.
    // In our case, we simply update the HRM measurement.
    hrmCounter++;

    //  100 <= HRM bps <=175
    if (hrmCounter == 175) {
        hrmCounter = 100;
    }

    hrServicePtr->updateHeartRate(hrmCounter);
}

void periodicCallback(void)
{
    led1 = !led1; /* Do blinky on LED1 while we're waiting for BLE events */

    if (BLE::Instance().getGapState().connected) {
        eventQueue.post(updateSensorValue);
    }
}

void onBleInitError(BLE &ble, ble_error_t error)
{
    (void)ble;
    (void)error;
   /* Initialization error handling should go here */
}

void bleInitComplete(BLE::InitializationCompleteCallbackContext *params)
{
    BLE&        ble   = params->ble;
    ble_error_t error = params->error;

    if (error != BLE_ERROR_NONE) {
        onBleInitError(ble, error);
        return;
    }

    if (ble.getInstanceID() != BLE::DEFAULT_INSTANCE) {
        return;
    }

    ble.gap().onDisconnection(disconnectionCallback);

    /* Setup primary service. */
    hrServicePtr = new HeartRateService(ble, hrmCounter, HeartRateService::LOCATION_FINGER);

    /* Setup advertising. */
    ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE);
    ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_16BIT_SERVICE_IDS, (uint8_t *)uuid16_list, sizeof(uuid16_list));
    ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::GENERIC_HEART_RATE_SENSOR);
    ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)DEVICE_NAME, sizeof(DEVICE_NAME));
    ble.gap().setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED);
    ble.gap().setAdvertisingInterval(1000); /* 1000ms */
    ble.gap().startAdvertising();
}

void scheduleBleEventsProcessing(BLE::OnEventsToProcessCallbackContext* context) {
    BLE &ble = BLE::Instance();
    eventQueue.post(Callback<void()>(&ble, &BLE::processEvents));
}

int main()
{
    eventQueue.post_every(500, periodicCallback);

    BLE &ble = BLE::Instance();
    ble.onEventsToProcess(scheduleBleEventsProcessing);
    ble.init(bleInitComplete);

    while (true) {
        eventQueue.dispatch();
    }

    return 0;
}