Application for nRF51822 mbed KIT that controls the intensity of LED2 using the BLE UART Service. Works with the Android App BLE_mbed_Remote available here https://github.com/bennthomsen/BLE_mbed_Remote

Dependencies:   BLE_API mbed nRF51822

Fork of BLE_UART_LEDControl_Echo by UCL IoT

This program demonstrates the use of the BLE UART Service to receive and send commands in order to remotely control the operation. In this example the intensity of LED2 can be remotely controlled.

The program accepts commands of the form "led2 0.1" over the BLE UART Service and uses these to set the duty cycle of the PWM Output that is connected to LED2 on the nRF51822 mbed KIT.

An Example Android App is available here https://github.com/bennthomsen/BLE_mbed_Remote. The complete source code and Android Studio Project files are available and can simply be pulled into Android Studio. The App implements sending of text, LED on off Button and a slider to control the LED brightness. At this stage setting the switch to off sets the PWM duty cycle to 0.0, however due to the PWMOut implementation in mbed the LED is not completely off at this point.

main.cpp

Committer:
yihui
Date:
2014-05-26
Revision:
0:e910d9bb040f
Child:
2:e060367b9024

File content as of revision 0:e910d9bb040f:

/* 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 "nRF51822n.h"

#define BLE_UUID_NUS_SERVICE            0x0001                       /**< The UUID of the Nordic UART Service. */
#define BLE_UUID_NUS_TX_CHARACTERISTIC  0x0002                       /**< The UUID of the TX Characteristic. */
#define BLE_UUID_NUS_RX_CHARACTERISTIC  0x0003                       /**< The UUID of the RX Characteristic. */

#ifdef DEBUG
#define LOG(args...)    pc.printf(args)

Serial pc(USBTX, USBRX);
#else
#define LOG(args...)
#endif

nRF51822n   nrf;                /* BLE radio driver */

DigitalOut  led1(p1);
DigitalOut  advertisingStateLed(p30);

// The Nordic UART Service
uint8_t uart_base_uuid[] = {0x6e, 0x40, 0x01, 0x00, 0xb5, 0xa3, 0xf3, 0x93, 0xe0, 0xa9, 0xe5,0x0e, 0x24, 0xdc, 0xca, 0x9e};
uint8_t txPayload[8] = {0,};
uint8_t rxPayload[8] = {0,};
GattService        uartService (uart_base_uuid);
GattCharacteristic txCharacteristic (BLE_UUID_NUS_TX_CHARACTERISTIC, 1, 8,
                                     GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE_WITHOUT_RESPONSE);
GattCharacteristic rxCharacteristic (BLE_UUID_NUS_RX_CHARACTERISTIC, 1, 8,
                                     GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY);

/* Advertising data and parameters */
GapAdvertisingData   advData;
GapAdvertisingData   scanResponse;
GapAdvertisingParams advParams ( GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED );

uint16_t             uuid16_list[] = {BLE_UUID_NUS_SERVICE};

/**************************************************************************/
/*!
    @brief  This custom class can be used to override any GapEvents
            that you are interested in handling on an application level.
*/
/**************************************************************************/
class GapEventHandler : public GapEvents
{
    //virtual void onTimeout(void) {}

    virtual void onConnected(void) {
        advertisingStateLed = 0;
        LOG("Connected!\n\r");
    }

    /* When a client device disconnects we need to start advertising again. */
    virtual void onDisconnected(void) {
        nrf.getGap().startAdvertising(advParams);
        advertisingStateLed = 1;
        LOG("Disconnected!\n\r");
        LOG("Restarting the advertising process\n\r");
    }
};

/**************************************************************************/
/*!
    @brief  This custom class can be used to override any GattServerEvents
            that you are interested in handling on an application level.
*/
/**************************************************************************/
class GattServerEventHandler : public GattServerEvents
{
    virtual void onDataSent(uint16_t charHandle) {
        if (charHandle == txCharacteristic.handle) {
            LOG("onDataSend()\n\r");

        }
    }

    virtual void onDataWritten(uint16_t charHandle) {
        if (charHandle == txCharacteristic.handle) {
            LOG("onDataWritten()\n\r");
            nrf.getGattServer().readValue(txCharacteristic.handle, txPayload, 8); // Current APIs don't provide the length of the payload
            LOG("ECHO: %s\n\r", (char *)txPayload);
            nrf.getGattServer().updateValue(rxCharacteristic.handle, txPayload, 8);
        }
    }

    virtual void onUpdatesEnabled(uint16_t charHandle) {
        LOG("onUpdateEnabled\n\r");
    }

    virtual void onUpdatesDisabled(uint16_t charHandle) {
        LOG("onUpdatesDisabled\n\r");
    }

    //virtual void onConfirmationReceived(uint16_t charHandle) {}
};

/**************************************************************************/
/*!
    @brief  Program entry point
*/
/**************************************************************************/
int main(void)
{

    /* Setup an event handler for GAP events i.e. Client/Server connection events. */
    nrf.getGap().setEventHandler(new GapEventHandler());
    nrf.getGattServer().setEventHandler(new GattServerEventHandler());

    /* Initialise the nRF51822 */
    nrf.init();

    /* Make sure we get a clean start */
    nrf.reset();

    /* Add BLE-Only flag and complete service list to the advertising data */
    advData.addFlags(GapAdvertisingData::BREDR_NOT_SUPPORTED);
    advData.addData(GapAdvertisingData::COMPLETE_LIST_16BIT_SERVICE_IDS,
                    (uint8_t*)uuid16_list, sizeof(uuid16_list));

    advData.addData(GapAdvertisingData::SHORTENED_LOCAL_NAME,
                    (uint8_t*)"BLE UART", sizeof("BLE UART") - 1);

    advData.addAppearance(GapAdvertisingData::UNKNOWN);
    nrf.getGap().setAdvertisingData(advData, scanResponse);

    /* UART Service */
    uartService.addCharacteristic(rxCharacteristic);
    uartService.addCharacteristic(txCharacteristic);
    nrf.getGattServer().addService(uartService);

    /* Start advertising (make sure you've added all your data first) */
    nrf.getGap().startAdvertising(advParams);
    
    advertisingStateLed = 1;

    /* Do blinky on LED1 while we're waiting for BLE events */
    for (;;) {
        led1 = !led1;
        wait(1);
    }
}