File content as of revision 2:504d4bd0e684:

/* 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 "Gap.h"
#include "ble/GattCharacteristic.h"
#include "ble/UUID.h"
#include "ble/DiscoveredCharacteristic.h"
#include "ble/DiscoveredService.h"
#include "mbed.h"
#include "ble/BLE.h"
#include "ble/services/HeartRateService.h"
#include "ble/services/BatteryService.h"
#include "ble/services/DeviceInformationService.h"

DigitalOut led1(LED1);
Serial uart(USBTX, USBRX, 115200);

const static char     DEVICE_NAME[]        = "DELTA_HRM_CEN";
static const uint16_t uuid16_list[]        = {GattService::UUID_HEART_RATE_SERVICE,
                                              GattService::UUID_DEVICE_INFORMATION_SERVICE};
static volatile bool  triggerSensorPolling = false;

uint8_t hrmCounter = 100; // init HRM to 100bps
const static char     PEER_NAME[]        = "DELTA_HRM1";

HeartRateService         *hrService;
DeviceInformationService *deviceInfo;

void advertisementCallback(const Gap::AdvertisementCallbackParams_t *params) {
    for (uint8_t i = 0; i < params->advertisingDataLen; ++i) {
        const uint8_t record_length = params->advertisingData[i];
        if (record_length == 0) continue;
        const uint8_t type = params->advertisingData[i + 1];
        const uint8_t* value = params->advertisingData + i + 2;
        const uint8_t value_length = record_length - 1;

        if(type == GapAdvertisingData::COMPLETE_LOCAL_NAME) {
            if ((value_length == sizeof(PEER_NAME)) && (memcmp(value, PEER_NAME, value_length) == 0)) {
                uart.printf("%s ", value);
                uart.printf(", adv peerAddr [%02x %02x %02x %02x %02x %02x], rssi %d, isScanResponse %u, AdvertisementType %u\r\n",
                    params->peerAddr[5], params->peerAddr[4], params->peerAddr[3], params->peerAddr[2],
                    params->peerAddr[1], params->peerAddr[0], params->rssi, params->isScanResponse, params->type
                );
                BLE::Instance(BLE::DEFAULT_INSTANCE).gap().stopScan();
                BLE::Instance(BLE::DEFAULT_INSTANCE).gap().connect(params->peerAddr, Gap::ADDR_TYPE_RANDOM_STATIC, NULL, NULL);
                break;
            }
        }
        i += record_length;
    }
}

void serviceDiscoveryCallback(const DiscoveredService *service) {
    uart.printf("serviceDiscoveryCallback\r\n");
    if (service->getUUID().shortOrLong() == UUID::UUID_TYPE_SHORT) {
        uart.printf("S UUID-%x attrs[%u %u]\r\n", service->getUUID().getShortUUID(), service->getStartHandle(), service->getEndHandle());
    } else {
        uart.printf("S UUID-");
        const uint8_t *longUUIDBytes = service->getUUID().getBaseUUID();
        for (unsigned i = 0; i < UUID::LENGTH_OF_LONG_UUID; i++) {
            uart.printf("%02x", longUUIDBytes[i]);
        }
        uart.printf(" attrs[%u %u]\r\n", service->getStartHandle(), service->getEndHandle());
    }
}

void characteristicDiscoveryCallback(const DiscoveredCharacteristic *characteristicP) {
    if (characteristicP->getUUID().shortOrLong() == UUID::UUID_TYPE_SHORT) {
        uart.printf("  C UUID-%x valueAttr[%u] props[%x]\r\n", characteristicP->getUUID().getShortUUID(), characteristicP->getValueHandle(), (uint8_t)characteristicP->getProperties().broadcast());
        if (characteristicP->getUUID().getShortUUID() == 0x2a37) { /* !ALERT! Alter this filter to suit your device. */   
            uint16_t value = BLE_HVX_NOTIFICATION;
            BLE::Instance(BLE::DEFAULT_INSTANCE).gattClient().write(GattClient::GATT_OP_WRITE_REQ, characteristicP->getConnectionHandle(), characteristicP->getValueHandle() + 1, 2, (uint8_t *)&value);
        }
    }
    else {
        uart.printf("  C UUID-");
        const uint8_t *longUUIDBytes = characteristicP->getUUID().getBaseUUID();
        for (unsigned i = (UUID::LENGTH_OF_LONG_UUID) - 1; i < UUID::LENGTH_OF_LONG_UUID; i--) {
            uart.printf("%02x ", longUUIDBytes[i]);
        }
        uart.printf(" valueAttr[%u] props[%x]\r\n", characteristicP->getValueHandle(), (uint8_t)characteristicP->getProperties().broadcast());
    }
}

void discoveryTerminationCallback(Gap::Handle_t connectionHandle) {
    uart.printf("terminated SD for handle %u\r\n", connectionHandle);
}

void connectionCallback(const Gap::ConnectionCallbackParams_t *params) {
    uart.printf("connectionCallback\r\n");
    if (params->role == Gap::CENTRAL) {
        BLE::Instance(BLE::DEFAULT_INSTANCE).gattClient().onServiceDiscoveryTermination(discoveryTerminationCallback);
        BLE::Instance(BLE::DEFAULT_INSTANCE).gattClient().launchServiceDiscovery(params->handle, serviceDiscoveryCallback, characteristicDiscoveryCallback);
    }
}

void dataReadCallback(const GattReadCallbackParams *response) {
    
}

void dataWriteCallback(const GattWriteCallbackParams *response) {
    
}

void hvxCallback(const GattHVXCallbackParams *response) {
    uart.printf("hvxCallback\r\n");
    for (unsigned index = 0; index < response->len; index++) {
        uart.printf("[%02x]", response->data[index]);
    }
    uart.printf("\r\n");
}

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

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

    /* Note that the periodicCallback() executes in interrupt context, so it is safer to do
     * heavy-weight sensor polling from the main thread. */
    triggerSensorPolling = true;
}

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

    if (error != BLE_ERROR_NONE) {
        return;
    }

    //Register callback function
    ble.gap().onConnection(connectionCallback);
    ble.gap().onDisconnection(disconnectionCallback);
    ble.gattClient().onDataRead(dataReadCallback);
    ble.gattClient().onDataWrite(dataWriteCallback);
    ble.gattClient().onHVX(hvxCallback);

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

    /* Setup auxiliary service. */
    deviceInfo = new DeviceInformationService(ble, "DELTA", "NQ620", "SN1", "hw-rev1", "fw-rev1", "soft-rev1");

    /* 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(160); /* 160ms */
    ble.gap().startAdvertising();
    
    //Central - start scan
    ble.gap().setScanParams(500, 400);
    ble.gap().startScan(advertisementCallback);
}

int main(void)
{
    led1 = 1;
    Ticker ticker;
    ticker.attach(periodicCallback, 1); // blink LED every second

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

    /* SpinWait for initialization to complete. This is necessary because the
     * BLE object is used in the main loop below. */
    while (ble.hasInitialized()  == false) { /* spin loop */ }

    ble.setTxPower(0);
    
    // infinite loop
    while (1) {
        // check for trigger from periodicCallback()
        if (triggerSensorPolling && ble.getGapState().connected) {
            triggerSensorPolling = false;

            // Do blocking calls or whatever is necessary for sensor polling.
            // In our case, we simply update the HRM measurement.
            hrmCounter++;
            if (hrmCounter == 175) { //  100 <= HRM bps <=175
                hrmCounter = 100;
            }

            hrService->updateHeartRate(hrmCounter);
        } else {
            ble.waitForEvent(); // low power wait for event
        }
    }
}