This example program shows how to set up a GAP advertising packet to broadcast data from the device out to anyone who may be listening.

Dependencies:   BLE_API mbed nRF51822

Fork of BLE_EvothingsExample_GAP by Blackstone Engineering

Intro

This code is meant to demonstrate how to use the GAP advertising layer to transmit data. Keep in mind you only have 26B of data in the Manufacturer data field to use.

Video of use

Details

Fill in the data you want to transmit by changing the following line, try using the string representation by changing hte "CHangeThisData" field or send hex data by altering the hex data field.

// You have up to 26 bytes of advertising data to use.
const static uint8_t AdvData[] = {"ChangeThisData"};             // example of character data
//const static uint8_t AdvData[] = {0x01,0x02,0x03,0x04,0x05};   // example of hex data

Name Device

Optionally you can give your device a name by uncommenting the following two lines

//const static char     DEVICE_NAME[]        = "ChangeMe!!"; // change this
...
//ble.accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)DEVICE_NAME, sizeof(DEVICE_NAME));

Add Disconnection Callback

This code is bare bones and as such does not restart advertising when disconnected from a device. To add this functionality into your code please add the following callback

// Restart advertising when phone app disconnects
void disconnectionCallback(Gap::Handle_t handle, Gap::DisconnectionReason_t reason)
{
    ble.startAdvertising(); 
}

and the following initialization to your main function

int 
main(void)
{
...
ble.onDisconnection(disconnectionCallback);
...

Viewing Data

You can use either the LightBlue app on iOS or the nRF Master Control Panel application on Android to view the advertising data. Alternatively you can use a custom Evothings App to view the data.

Evothings?

Evothings is a rapid prototyping environment that uses cordova to enable you to rapidly develop smartphone applications in Javascript. Please download the Evothings workbench to your computer and the Evothings client to your smartphone. In the Evothings Workbench you will find an example program called "mbed Evothings GAP", this Evothings Smartphone App is meant to be used with the above embedded mbed code. For instructions on how to use Evothings please see the reference section below.

Reference

Committer:
andresag
Date:
Tue Jan 12 12:00:16 2016 +0000
Revision:
15:7e06fce6e4f8
Parent:
14:1c15d473b42f
Add missing license information to source code.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andresag 15:7e06fce6e4f8 1 /* mbed Microcontroller Library
andresag 15:7e06fce6e4f8 2 * Copyright (c) 2006-2015 ARM Limited
andresag 15:7e06fce6e4f8 3 *
andresag 15:7e06fce6e4f8 4 * Licensed under the Apache License, Version 2.0 (the "License");
andresag 15:7e06fce6e4f8 5 * you may not use this file except in compliance with the License.
andresag 15:7e06fce6e4f8 6 * You may obtain a copy of the License at
andresag 15:7e06fce6e4f8 7 *
andresag 15:7e06fce6e4f8 8 * http://www.apache.org/licenses/LICENSE-2.0
andresag 15:7e06fce6e4f8 9 *
andresag 15:7e06fce6e4f8 10 * Unless required by applicable law or agreed to in writing, software
andresag 15:7e06fce6e4f8 11 * distributed under the License is distributed on an "AS IS" BASIS,
andresag 15:7e06fce6e4f8 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
andresag 15:7e06fce6e4f8 13 * See the License for the specific language governing permissions and
andresag 15:7e06fce6e4f8 14 * limitations under the License.
andresag 15:7e06fce6e4f8 15 */
andresag 15:7e06fce6e4f8 16
mbedAustin 0:5375be4301ed 17 #include "mbed.h"
andresag 14:1c15d473b42f 18 #include "ble/BLE.h"
andresag 14:1c15d473b42f 19
andresag 14:1c15d473b42f 20 /* Optional: Device Name, add for human read-ability */
andresag 14:1c15d473b42f 21 const static char DEVICE_NAME[] = "ChangeMe!!";
andresag 14:1c15d473b42f 22
andresag 14:1c15d473b42f 23 /* You have up to 26 bytes of advertising data to use. */
andresag 14:1c15d473b42f 24 const static uint8_t AdvData[] = {0x01,0x02,0x03,0x04,0x05}; /* Example of hex data */
andresag 14:1c15d473b42f 25 //const static uint8_t AdvData[] = {"ChangeThisData"}; /* Example of character data */
mbedAustin 0:5375be4301ed 26
andresag 14:1c15d473b42f 27 /* Optional: Restart advertising when peer disconnects */
andresag 14:1c15d473b42f 28 void disconnectionCallback(const Gap::DisconnectionCallbackParams_t *params)
andresag 14:1c15d473b42f 29 {
andresag 14:1c15d473b42f 30 BLE::Instance().gap().startAdvertising();
andresag 14:1c15d473b42f 31 }
andresag 14:1c15d473b42f 32 /**
andresag 14:1c15d473b42f 33 * This function is called when the ble initialization process has failed
andresag 14:1c15d473b42f 34 */
andresag 14:1c15d473b42f 35 void onBleInitError(BLE &ble, ble_error_t error)
andresag 14:1c15d473b42f 36 {
andresag 14:1c15d473b42f 37 /* Avoid compiler warnings */
andresag 14:1c15d473b42f 38 (void) ble;
andresag 14:1c15d473b42f 39 (void) error;
andresag 14:1c15d473b42f 40
andresag 14:1c15d473b42f 41 /* Initialization error handling should go here */
andresag 14:1c15d473b42f 42 }
mbedAustin 0:5375be4301ed 43
andresag 14:1c15d473b42f 44 /**
andresag 14:1c15d473b42f 45 * Callback triggered when the ble initialization process has finished
andresag 14:1c15d473b42f 46 */
andresag 14:1c15d473b42f 47 void bleInitComplete(BLE::InitializationCompleteCallbackContext *params)
andresag 14:1c15d473b42f 48 {
andresag 14:1c15d473b42f 49 BLE& ble = params->ble;
andresag 14:1c15d473b42f 50 ble_error_t error = params->error;
andresag 14:1c15d473b42f 51
andresag 14:1c15d473b42f 52 if (error != BLE_ERROR_NONE) {
andresag 14:1c15d473b42f 53 /* In case of error, forward the error handling to onBleInitError */
andresag 14:1c15d473b42f 54 onBleInitError(ble, error);
andresag 14:1c15d473b42f 55 return;
andresag 14:1c15d473b42f 56 }
mbedAustin 5:fff16d283dcf 57
andresag 14:1c15d473b42f 58 /* Ensure that it is the default instance of BLE */
andresag 14:1c15d473b42f 59 if(ble.getInstanceID() != BLE::DEFAULT_INSTANCE) {
andresag 14:1c15d473b42f 60 return;
andresag 14:1c15d473b42f 61 }
andresag 14:1c15d473b42f 62
andresag 14:1c15d473b42f 63 /* Set device name characteristic data */
andresag 14:1c15d473b42f 64 ble.gap().setDeviceName((const uint8_t *) DEVICE_NAME);
andresag 14:1c15d473b42f 65
andresag 14:1c15d473b42f 66 /* Optional: add callback for disconnection */
andresag 14:1c15d473b42f 67 ble.gap().onDisconnection(disconnectionCallback);
mbedAustin 1:0692bee84264 68
andresag 14:1c15d473b42f 69 /* Sacrifice 3B of 31B to Advertising Flags */
andresag 14:1c15d473b42f 70 ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE );
andresag 14:1c15d473b42f 71 ble.gap().setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED);
andresag 14:1c15d473b42f 72
andresag 14:1c15d473b42f 73 /* Sacrifice 2B of 31B to AdvType overhead, rest goes to AdvData array you define */
andresag 14:1c15d473b42f 74 ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::MANUFACTURER_SPECIFIC_DATA, AdvData, sizeof(AdvData));
andresag 14:1c15d473b42f 75
andresag 14:1c15d473b42f 76 /* Optional: Add name to device */
andresag 14:1c15d473b42f 77 //ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)DEVICE_NAME, sizeof(DEVICE_NAME));
andresag 14:1c15d473b42f 78
andresag 14:1c15d473b42f 79 /* Set advertising interval. Longer interval == longer battery life */
andresag 14:1c15d473b42f 80 ble.gap().setAdvertisingInterval(100); /* 100ms */
andresag 14:1c15d473b42f 81
andresag 14:1c15d473b42f 82 /* Start advertising */
andresag 14:1c15d473b42f 83 ble.gap().startAdvertising();
mbedAustin 8:5442739198ec 84 }
mbedAustin 8:5442739198ec 85
mbedAustin 1:0692bee84264 86 int main(void)
mbedAustin 0:5375be4301ed 87 {
andresag 14:1c15d473b42f 88 BLE& ble = BLE::Instance(BLE::DEFAULT_INSTANCE);
andresag 14:1c15d473b42f 89
andresag 14:1c15d473b42f 90 /* Initialize BLE baselayer, always do this first! */
andresag 14:1c15d473b42f 91 ble.init(bleInitComplete);
mbedAustin 1:0692bee84264 92
andresag 14:1c15d473b42f 93 /* Infinite loop waiting for BLE events */
andresag 14:1c15d473b42f 94 while (true) {
andresag 14:1c15d473b42f 95 /* Save power while waiting for callback events */
andresag 14:1c15d473b42f 96 ble.waitForEvent();
mbedAustin 1:0692bee84264 97 }
mbedAustin 1:0692bee84264 98 }