UCL IoT / Mbed 2 deprecated BLE_UART_LEDControl_Echo

Demonstration code showing how to control an LED over Bluetooth Low Energy using the UARTService

Dependencies:   BLE_API mbed nRF51822

Fork of BLE_LoopbackUART by Bluetooth Low Energy

This programme demonstrates the use of the UARTService to send command strings over Bluetooth Low Energy (BLE) to control devices attached to the nRF51822 board.

In this example you can use a BLE connection from smart phone to turn on and off LED2 on the board.

Sending the character string "led2 on" will turn the LED on and "led2 off" will turn it off.

The command that is received is also echoed back via BLE to the sending device.

You can use the nRF UART App on and Android or iOS smart phone with BLE to test this out https://www.nordicsemi.com/eng/Products/nRFready-Demo-APPS

I have also ported the source code for the Android app into Android studio which should be a good starting point for developing your own custom App https://github.com/bennthomsen/nRF_UART. If you want to start using this within Android Studio create for own fork in GitHub and then from within Android Studio VCS>Checkout from Version Control>GitHub

main.cpp

Committer:
rgrover1
Date:
2014-11-28
Revision:
10:633cec718bf4
Parent:
6:e0fc9072e853
Child:
12:36a9f01cfa0a

File content as of revision 10:633cec718bf4:

/* mbed Microcontroller Library
 * Copyright (c) 2006-2013 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.h"
#include "BLEDevice.h"

#include "UARTService.h"

#define NEED_CONSOLE_OUTPUT 0 /* Set this if you need debug messages on the console;
                               * it will have an impact on code-size and power consumption. */

#if NEED_CONSOLE_OUTPUT
#define DEBUG(...) { printf(__VA_ARGS__); }
#else
#define DEBUG(...) /* nothing */
#endif /* #if NEED_CONSOLE_OUTPUT */

BLEDevice  ble;
DigitalOut led1(LED1);

UARTService *uartServicePtr;

void disconnectionCallback(Gap::Handle_t handle, Gap::DisconnectionReason_t reason)
{
    DEBUG("Disconnected!\n\r");
    DEBUG("Restarting the advertising process\n\r");
    ble.startAdvertising();
}

void onDataWritten(const GattCharacteristicWriteCBParams *params)
{
    if ((uartServicePtr != NULL) && (params->charHandle == uartServicePtr->getTXCharacteristicHandle())) {
        uint16_t bytesRead = params->len;
        DEBUG("received %u bytes\n\r", bytesRead);
        ble.updateCharacteristicValue(uartServicePtr->getRXCharacteristicHandle(), params->data, bytesRead);
    }
}

void periodicCallback(void)
{
    led1 = !led1;
}

int main(void)
{
    led1 = 1;
    Ticker ticker;
    ticker.attach(periodicCallback, 1);

    DEBUG("Initialising the nRF51822\n\r");
    ble.init();
    ble.onDisconnection(disconnectionCallback);
    ble.onDataWritten(onDataWritten);

    /* setup advertising */
    ble.accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED);
    ble.setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED);
    ble.accumulateAdvertisingPayload(GapAdvertisingData::SHORTENED_LOCAL_NAME,
                                     (const uint8_t *)"BLE UART", sizeof("BLE UART") - 1);
    ble.accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_128BIT_SERVICE_IDS,
                                     (const uint8_t *)UARTServiceUUID_reversed, sizeof(UARTServiceUUID_reversed));

    ble.setAdvertisingInterval(Gap::MSEC_TO_ADVERTISEMENT_DURATION_UNITS(1000));
    ble.startAdvertising();

    UARTService uartService(ble);
    uartServicePtr = &uartService;

    while (true) {
        ble.waitForEvent();
    }
}