File content as of revision 34:0a5b9e4e7680:

#include "mbed.h"
#include "ble/BLE.h"

DigitalOut led(P0_4, 0);
uint16_t customServiceUUID  = 0xA000;
uint16_t readCharUUID       = 0xA001;
uint16_t writeCharUUID      = 0xA002;

const static char     DEVICE_NAME[]        = "timesync2"; // change this
static const uint16_t uuid16_list[]        = {0xFFFF}; //Custom UUID, FFFF is reserved for development


static uint8_t readValue[10] = {0};
ReadOnlyArrayGattCharacteristic<uint8_t, sizeof(readValue)> readChar(readCharUUID, readValue);

static uint8_t writeValue[10] = {0};
WriteOnlyArrayGattCharacteristic<uint8_t, sizeof(writeValue)> writeChar(writeCharUUID, writeValue);

/* Set up custom service */
GattCharacteristic *characteristics[] = {&readChar, &writeChar};
GattService        customService(customServiceUUID, characteristics, sizeof(characteristics) / sizeof(GattCharacteristic *));

/*
 *  Restart advertising when phone app disconnects
*/
void disconnectionCallback(const Gap::DisconnectionCallbackParams_t *)
{
    led = 0;    // just in case
    BLE::Instance(BLE::DEFAULT_INSTANCE).gap().startAdvertising();
}

/*
 *  Handle writes to writeCharacteristic
*/
void writeCharCallback(const GattWriteCallbackParams *params)
{
    /* Check to see what characteristic was written, by handle */
    if(params->handle == writeChar.getValueHandle()) {
        // since LED is pullup mode
        led = 1;
        wait(1.0);
        led = 0;
    }
}


void bleInitComplete(BLE::InitializationCompleteCallbackContext *params)
{
    BLE &ble          = params->ble;
    ble_error_t error = params->error;
    
    if (error != BLE_ERROR_NONE) {
        return;
    }

    ble.gap().onDisconnection(disconnectionCallback);
    ble.gattServer().onDataWritten(writeCharCallback);

    /* Setup advertising */
    ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE); // BLE only, no classic BT
    ble.gap().setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED); // advertising type
    ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)DEVICE_NAME, sizeof(DEVICE_NAME)); // add name
    ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_16BIT_SERVICE_IDS, (uint8_t *)uuid16_list, sizeof(uuid16_list)); // UUID's broadcast in advertising packet
    ble.gap().setAdvertisingInterval(400); // 500ms.

    /* Add our custom service */
    ble.addService(customService);

    /* Start advertising */
    ble.gap().startAdvertising();
}

/*
 *  Main loop
*/
int main(void)
{   
    NRF_TWI0->ENABLE = TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos;
    NRF_POWER->TASKS_LOWPWR = 1;
    NRF_ADC->ENABLE =   (ADC_ENABLE_ENABLE_Disabled << ADC_ENABLE_ENABLE_Pos); 
    NRF_POWER->DCDCEN = 0x00000001;
    
    BLE& ble = BLE::Instance(BLE::DEFAULT_INSTANCE);
    ble.init(bleInitComplete);
    ble.setTxPower(-4);
    
    /* 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 */ }

    /* Infinite loop waiting for BLE interrupt events */
    while (true) {
        ble.waitForEvent(); /* Save power */
    }
}