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CurieBLE : BLEDescriptor class

BLEDescriptor constructor

Description

Descriptors are defined attributes that describe a characteristic value

Syntax

  • BLEDescriptor(const char* uuid, const unsigned char value[], unsigned char valueSize);
  • BLEDescriptor(const char* uuid, const char* value);

Parameters

  • UUID: standard 16-bit characteristic UUID
  • properties: what remote clients will be able to get notifications if this characteristic changes. It can assume the following values:
    • BLERead
    • BLEWrite
    • BLENotify

  • uuid: UUID of descriptor
  • value: value data
  • valueLength: length of value data in bytes

or

  • value: string value

Example

/*
 * Copyright (c) 2016 Intel Corporation.  All rights reserved.
 * See the bottom of this file for the license terms.
 */


#include <CurieBLE.h>

BLEPeripheral blePeripheral;  // BLE Peripheral Device (the board you're programming)
BLEService ledService("19B10000-E8F2-537E-4F6C-D104768A1214"); // BLE LED Service

// BLE LED Switch Characteristic - custom 128-bit UUID, read and writable by central
BLEUnsignedCharCharacteristic switchCharacteristic("19B10001-E8F2-537E-4F6C-D104768A1214", BLERead | BLEWrite);

const int ledPin = 13; // pin to use for the LED

void setup() {
  Serial.begin(9600);

  // set LED pin to output mode
  pinMode(ledPin, OUTPUT);

  // set advertised local name and service UUID:
  blePeripheral.setLocalName("LED");
  blePeripheral.setAdvertisedServiceUuid(ledService.uuid());

  // add service and characteristic:
  blePeripheral.addAttribute(ledService);
  blePeripheral.addAttribute(switchCharacteristic);

  // set the initial value for the characeristic:
  switchCharacteristic.setValue(0);

  // begin advertising BLE service:
  blePeripheral.begin();

  Serial.println("BLE LED Peripheral");
}

void loop() {
  // listen for BLE peripherals to connect:
  BLECentral central = blePeripheral.central();

  // if a central is connected to peripheral:
  if (central) {
    Serial.print("Connected to central: ");
    // print the central's MAC address:
    Serial.println(central.address());

    // while the central is still connected to peripheral:
    while (central.connected()) {
      // if the remote device wrote to the characteristic,
      // use the value to control the LED:
      if (switchCharacteristic.written()) {
        if (switchCharacteristic.value()) {   // any value other than 0
          Serial.println("LED on");
          digitalWrite(ledPin, HIGH);         // will turn the LED on
        } else {                              // a 0 value
          Serial.println(F("LED off"));
          digitalWrite(ledPin, LOW);          // will turn the LED off
        }
      }
    }

    // when the central disconnects, print it out:
    Serial.print(F("Disconnected from central: "));
    Serial.println(central.address());
  }
}

/*
   Copyright (c) 2016 Intel Corporation.  All rights reserved.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

See Also

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The text of the Arduino reference is licensed under a Creative Commons Attribution-ShareAlike 3.0 License. Code samples in the reference are released into the public domain.

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