This example creates a BLE beacon: a method of advertising a small amount of information to nearby devices. The information doesn't have to be human-readable; it can be in a format that only an application can use. Beacons are very easy to set up: the code for all beacons is the same, and only the information you want to advertise - the beacon payload - needs to change. he canonical source for this example lives at https://github.com/ARMmbed/mbed-os-example-ble/tree/master/BLE_Beacon

This example creates a BLE beacon: a method of advertising a small amount of information to nearby devices. The information doesn't have to be human-readable; it can be in a format that only an application can use.

Beacons are very easy to set up: the code for all beacons is the same, and only the information you want to advertise - the beacon payload - needs to change.

This example advertises a UUID, a major and minor number and the transmission strength. The major and minor numbers are an example of information that is not (normally) meaningful to humans, but that an application can use to identify the beacon and display related information. For example, if the major number is a store ID and the minor number is a location in that store, then a matching application can use these numbers to query a database and display location-specific information.

Running the application

Requirements

The sample application can be seen on any BLE scanner on a smartphone. If you don't have a scanner on your phone, please install :

- nRF Master Control Panel for Android.

- LightBlue for iPhone.

Hardware requirements are in the main readme.

Building instructions

Building with mbed CLI

If you'd like to use mbed CLI to build this, then you should refer to the main readme. The instructions here relate to using the developer.mbed.org Online Compiler

In order to build this example in the mbed Online Compiler, first import the example using the ‘Import’ button on the right hand side.

Next, select a platform to build for. This must either be a platform that supports BLE, for example the NRF51-DK, or one of the following:

List of platforms supporting Bluetooth Low Energy

Or you must also add a piece of hardware and the supporting library that includes a Bluetooth Low Energy driver for that hardware, for example the K64F or NUCLEO_F401RE with the X-NUCLEO-IDB05A1

List of components supporting Bluetooth Low Energy.

Once you have selected your platform, compile the example and drag and drop the resulting binary onto your board.

For general instructions on using the mbed Online Compiler, please see the mbed Handbook

Checking for success

Note: Screens captures depicted below show what is expected from this example if the scanner used is nRF Master Control Panel version 4.0.5. If you encounter any difficulties consider trying another scanner or another version of nRF Master Control Panel. Alternative scanners may require reference to their manuals.

  • Build the application and install it on your board as explained in the building instructions.
  • Open the BLE scanner on your phone.
  • Start a scan.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Beacon/raw-file/66b59f6860ed/img/start_scan.png

figure 1 How to start scan using nRF Master Control Panel 4.0.5

1. Find your device; it should be tagged as an `iBeacon` and observe its advertisements (there is no need to connect to the beacon).

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Beacon/raw-file/66b59f6860ed/img/discovery.png

figure 2 Scan results using nRF Master Control Panel 4.0.5

  • View the beacon's details; the exact steps depend on which scanner you're using.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Beacon/raw-file/66b59f6860ed/img/beacon_details.png

figure 3 Beacon details using nRF Master Control Panel 4.0.5

Tip: If you are in an area with many BLE devices, it may be difficult to identify your beacon. The simplest solution is to turn your board off and on, initiate a new scan on your BLE scanner every time, and look for the beacon that appears only when your board is on.

If you can see the beacon and all its information, the application worked properly.

For more information, see the mbed Classic version of this application.

Committer:
mbed_official
Date:
Tue Aug 08 14:15:10 2017 +0100
Revision:
40:abc2d39dfdde
Parent:
28:9090fe431353
Child:
45:0d307fc39fd0
Merge pull request #100 from 0xc0170/master

Updating mbed-os to mbed-os-5.5.4
.
Commit copied from https://github.com/ARMmbed/mbed-os-example-ble

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 3:41f6be68aefb 1 /* mbed Microcontroller Library
mbed_official 3:41f6be68aefb 2 * Copyright (c) 2006-2015 ARM Limited
mbed_official 3:41f6be68aefb 3 *
mbed_official 3:41f6be68aefb 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 3:41f6be68aefb 5 * you may not use this file except in compliance with the License.
mbed_official 3:41f6be68aefb 6 * You may obtain a copy of the License at
mbed_official 3:41f6be68aefb 7 *
mbed_official 3:41f6be68aefb 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 3:41f6be68aefb 9 *
mbed_official 3:41f6be68aefb 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 3:41f6be68aefb 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 3:41f6be68aefb 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 3:41f6be68aefb 13 * See the License for the specific language governing permissions and
mbed_official 3:41f6be68aefb 14 * limitations under the License.
mbed_official 3:41f6be68aefb 15 */
mbed_official 3:41f6be68aefb 16
mbed_official 12:af576944a152 17 #include <events/mbed_events.h>
mbed_official 3:41f6be68aefb 18 #include <mbed.h>
mbed_official 3:41f6be68aefb 19 #include "ble/BLE.h"
mbed_official 3:41f6be68aefb 20 #include "ble/services/iBeacon.h"
mbed_official 3:41f6be68aefb 21
mbed_official 3:41f6be68aefb 22 static iBeacon* ibeaconPtr;
mbed_official 3:41f6be68aefb 23
mbed_official 28:9090fe431353 24 static EventQueue eventQueue(/* event count */ 4 * EVENTS_EVENT_SIZE);
mbed_official 3:41f6be68aefb 25
mbed_official 3:41f6be68aefb 26 /**
mbed_official 3:41f6be68aefb 27 * This function is called when the ble initialization process has failled
mbed_official 3:41f6be68aefb 28 */
mbed_official 3:41f6be68aefb 29 void onBleInitError(BLE &ble, ble_error_t error)
mbed_official 3:41f6be68aefb 30 {
mbed_official 3:41f6be68aefb 31 /* Initialization error handling should go here */
mbed_official 3:41f6be68aefb 32 }
mbed_official 3:41f6be68aefb 33
mbed_official 3:41f6be68aefb 34 /**
mbed_official 3:41f6be68aefb 35 * Callback triggered when the ble initialization process has finished
mbed_official 3:41f6be68aefb 36 */
mbed_official 3:41f6be68aefb 37 void bleInitComplete(BLE::InitializationCompleteCallbackContext *params)
mbed_official 3:41f6be68aefb 38 {
mbed_official 3:41f6be68aefb 39 BLE& ble = params->ble;
mbed_official 3:41f6be68aefb 40 ble_error_t error = params->error;
mbed_official 3:41f6be68aefb 41
mbed_official 3:41f6be68aefb 42 if (error != BLE_ERROR_NONE) {
mbed_official 3:41f6be68aefb 43 /* In case of error, forward the error handling to onBleInitError */
mbed_official 3:41f6be68aefb 44 onBleInitError(ble, error);
mbed_official 3:41f6be68aefb 45 return;
mbed_official 3:41f6be68aefb 46 }
mbed_official 3:41f6be68aefb 47
mbed_official 3:41f6be68aefb 48 /* Ensure that it is the default instance of BLE */
mbed_official 3:41f6be68aefb 49 if(ble.getInstanceID() != BLE::DEFAULT_INSTANCE) {
mbed_official 3:41f6be68aefb 50 return;
mbed_official 3:41f6be68aefb 51 }
mbed_official 3:41f6be68aefb 52
mbed_official 3:41f6be68aefb 53 /**
mbed_official 3:41f6be68aefb 54 * The Beacon payload has the following composition:
mbed_official 3:41f6be68aefb 55 * 128-Bit / 16byte UUID = E2 0A 39 F4 73 F5 4B C4 A1 2F 17 D1 AD 07 A9 61
mbed_official 3:41f6be68aefb 56 * Major/Minor = 0x1122 / 0x3344
mbed_official 3:41f6be68aefb 57 * Tx Power = 0xC8 = 200, 2's compliment is 256-200 = (-56dB)
mbed_official 3:41f6be68aefb 58 *
mbed_official 3:41f6be68aefb 59 * Note: please remember to calibrate your beacons TX Power for more accurate results.
mbed_official 3:41f6be68aefb 60 */
mbed_official 3:41f6be68aefb 61 static const uint8_t uuid[] = {0xE2, 0x0A, 0x39, 0xF4, 0x73, 0xF5, 0x4B, 0xC4,
mbed_official 3:41f6be68aefb 62 0xA1, 0x2F, 0x17, 0xD1, 0xAD, 0x07, 0xA9, 0x61};
mbed_official 3:41f6be68aefb 63 uint16_t majorNumber = 1122;
mbed_official 3:41f6be68aefb 64 uint16_t minorNumber = 3344;
mbed_official 3:41f6be68aefb 65 uint16_t txPower = 0xC8;
mbed_official 3:41f6be68aefb 66 ibeaconPtr = new iBeacon(ble, uuid, majorNumber, minorNumber, txPower);
mbed_official 3:41f6be68aefb 67
mbed_official 3:41f6be68aefb 68 ble.gap().setAdvertisingInterval(1000); /* 1000ms. */
mbed_official 3:41f6be68aefb 69 ble.gap().startAdvertising();
mbed_official 3:41f6be68aefb 70 }
mbed_official 3:41f6be68aefb 71
mbed_official 3:41f6be68aefb 72 void scheduleBleEventsProcessing(BLE::OnEventsToProcessCallbackContext* context) {
mbed_official 3:41f6be68aefb 73 BLE &ble = BLE::Instance();
mbed_official 12:af576944a152 74 eventQueue.call(Callback<void()>(&ble, &BLE::processEvents));
mbed_official 3:41f6be68aefb 75 }
mbed_official 3:41f6be68aefb 76
mbed_official 3:41f6be68aefb 77 int main()
mbed_official 3:41f6be68aefb 78 {
mbed_official 3:41f6be68aefb 79 BLE &ble = BLE::Instance();
mbed_official 3:41f6be68aefb 80 ble.onEventsToProcess(scheduleBleEventsProcessing);
mbed_official 3:41f6be68aefb 81 ble.init(bleInitComplete);
mbed_official 3:41f6be68aefb 82
mbed_official 12:af576944a152 83 eventQueue.dispatch_forever();
mbed_official 3:41f6be68aefb 84
mbed_official 3:41f6be68aefb 85 return 0;
mbed_official 3:41f6be68aefb 86 }