mbed application to pair with Evothings App, demonstrates how to create a custom GAP advertising packet.
Dependencies: BLE_API mbed nRF51822
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.
Details
Fill in the data you want to transmit by changing the following line
/** You have up to 26 bytes of advertising data to use. Make up your own encoding for these 26bytes, send it across and decode it using the evothings app. */ 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));
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.
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); ...
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. Then grab the code from the github page, drag and drop the index.htm file into Evothings workbench and run it on the Evothings client.
Reference
main.cpp@4:d602b1c3aef4, 2015-03-10 (annotated)
- Committer:
- mbedAustin
- Date:
- Tue Mar 10 20:32:37 2015 +0000
- Revision:
- 4:d602b1c3aef4
- Parent:
- 3:e9646631084f
- Child:
- 5:fff16d283dcf
made device connectable instead of non-connectable, this is to allow iOS devices to connect and display the advertising info, because no iOS app will just show the advertising data, they have to connect... grrr....
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
mbedAustin | 1:0692bee84264 | 1 | |
mbedAustin | 1:0692bee84264 | 2 | // Headers necessary for mbed and BLE device mode |
mbedAustin | 0:5375be4301ed | 3 | #include "mbed.h" |
mbedAustin | 0:5375be4301ed | 4 | #include "BLEDevice.h" |
mbedAustin | 0:5375be4301ed | 5 | |
mbedAustin | 1:0692bee84264 | 6 | // BLE object |
mbedAustin | 1:0692bee84264 | 7 | BLEDevice ble; |
mbedAustin | 0:5375be4301ed | 8 | |
mbedAustin | 1:0692bee84264 | 9 | /** |
mbedAustin | 1:0692bee84264 | 10 | You have up to 26 bytes of advertising data to use. |
mbedAustin | 1:0692bee84264 | 11 | Make up your own encoding for these 26bytes, send it across |
mbedAustin | 1:0692bee84264 | 12 | and decode it using the evothings app. |
mbedAustin | 1:0692bee84264 | 13 | */ |
mbedAustin | 4:d602b1c3aef4 | 14 | //const static uint8_t AdvData[] = {"ChangeThisData"}; // example of character data |
mbedAustin | 4:d602b1c3aef4 | 15 | const static uint8_t AdvData[] = {0x01,0x02,0x03,0x04,0x05}; // example of hex data |
mbedAustin | 1:0692bee84264 | 16 | |
mbedAustin | 1:0692bee84264 | 17 | // main program |
mbedAustin | 1:0692bee84264 | 18 | int main(void) |
mbedAustin | 0:5375be4301ed | 19 | { |
mbedAustin | 1:0692bee84264 | 20 | // Initialize BLE baselayer, always do this first! |
mbedAustin | 1:0692bee84264 | 21 | ble.init(); |
mbedAustin | 1:0692bee84264 | 22 | |
mbedAustin | 1:0692bee84264 | 23 | // Sacrifice 3B of 31B to Advertising Flags |
mbedAustin | 1:0692bee84264 | 24 | ble.accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE ); |
mbedAustin | 4:d602b1c3aef4 | 25 | ble.setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED); |
mbedAustin | 1:0692bee84264 | 26 | |
mbedAustin | 1:0692bee84264 | 27 | // Sacrifice 2B of 31B to AdvType overhead, rest goes to AdvData array you define |
mbedAustin | 1:0692bee84264 | 28 | ble.accumulateAdvertisingPayload(GapAdvertisingData::MANUFACTURER_SPECIFIC_DATA, AdvData, sizeof(AdvData)); |
mbedAustin | 1:0692bee84264 | 29 | |
mbedAustin | 1:0692bee84264 | 30 | // Set advertising interval. Longer interval = longer battery life |
mbedAustin | 1:0692bee84264 | 31 | ble.setAdvertisingInterval(160); // 100ms; in multiples of 0.625ms. |
mbedAustin | 1:0692bee84264 | 32 | ble.startAdvertising(); |
mbedAustin | 1:0692bee84264 | 33 | |
mbedAustin | 1:0692bee84264 | 34 | // Infinite loop waiting for BLE events |
mbedAustin | 1:0692bee84264 | 35 | for (;;) { |
mbedAustin | 1:0692bee84264 | 36 | ble.waitForEvent(); // this saves battery |
mbedAustin | 1:0692bee84264 | 37 | } |
mbedAustin | 1:0692bee84264 | 38 | } |