Developing with

Bluetooth World 15 March 2016

mbed and Bluetooth LE

@janjongboom

Developer EvangelistInternet of Things

Choosing a vendor, not a chipown SDKs, IDEs, programming patterns

UnstreamlinedSingle-platform tools

No code sharing Lack of libraries, documentation

(since 2009)

mbed

Online IDE

Code sharing

Single way of building for all targets

91 boards supported

~200 staff working on it

170,000+ developers

Focused on prototyping

Building on top of mbedNew release: mbed OS

mbed OSOpen source embedded platform

Operating system for microcontrollers

Rock-solid HAL and libraries (e.g. Bluetooth)

One year on AA battery 0.137 mA

DifferencesTask scheduler

Automatic battery management

The embedded event loop is dead

while(1){

delay_ms(1);

}

yottaBuild tools and library management

Cross-platform (Windows, OS X, Linux, Browser)

Easily integrated in own workflow

Coming to uVision and new online IDE

Let's build something...

Get a boardMaxim MAX32610-based (???)

Nordic nRF51822-based

ST Nucleo IDB04A1

configure Install yotta yottadocs.mbed.com

Initialize project yottainit

Set up target yottatargetnrf51dk-gcc

Add BLE yottainstallble

github.com/ARMmbed/ble-examples

Built-in GATT services(e.g. heart rate)

1#include"ble/BLE.h"23conststaticcharDEVICE_NAME[]="HRM";4staticconstuint16_tuuid16_list[]={GattService::UUID_HEART_RATE_SERVICE};56staticuint8_thrmCounter=100;//initHRMto100bps78autohrServicePtr=newHeartRateService(9ble,hrmCounter,HeartRateService::LOCATION_FINGER);1011/*snip..configuration*/12ble.gap().setAdvertisingInterval(1000);13ble.gap().startAdvertising();

1voidupdateHr(void)2{3if(BLE::Instance().getGapState().connected){4hrmCounter++;56if(hrmCounter==175){7hrmCounter=100;8}910hrServicePtr->updateHeartRate(hrmCounter);11}12}1314voidapp_start(int,char**)15{16Scheduler::postCallback(updateHr).period(minar::milliseconds(500));17}

Building$yottabuild

$cpbuild/heartrate.hex/Volumes/MBED

1classButtonService{2uint16_tBUTTON_SERVICE_UUID=0xA000;3uint16_tBUTTON_STATE_CHARACTERISTIC_UUID=0xA001;45ButtonService(BLE&_ble,boolbuttonPressedInitial):6ble(_ble),buttonState(BUTTON_STATE_CHARACTERISTIC_UUID,7GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY)8{9GattCharacteristic*charTable[]={&buttonState};10GattServiceservice(ButtonService::BUTTON_SERVICE_UUID,/*chars*/);11ble.gattServer().addService(buttonService);12}1314voidupdateButtonState(boolnewState){15ble.gattServer().write(buttonState.getValueHandle(),newState);16}1718BLE&ble;19ReadOnlyGattCharacteristic<bool>buttonState;20};

Physical WebWalk up and use anything

Physical Web beacon

http://goo.gl/a1b4cd

(Eddystone protocol)

Official Eddystone library for mbed OS

1#include"EddystoneService.h"23autoeddyServicePtr=newEddystoneService(4ble,defaultAdvPowerLevels,radioPowerLevels);56constchar*url="http://mbed.com";7eddyServicePtr->setURLData(url);89eddyServicePtr->startBeaconService();

Web BluetoothGATT from JS

Some great demo's: http://thebubbleworks.com

http://rollingspider.xyz/aa73bc21

http://meeting.arm.com/tesla

One problem...Eddystone is non-connectable

No service UUIDs in frames

... send two frames!

http://blog.mbed.com/post/137093070607/

End-to-endDemo time!

Juggling visualizerOn device, accelerometer service

Sends out URL

Web app that plots values over time

http://github.com/web-bluetooth/juggling

Get hacking!

Thank you!http://janjongboom.com