THE JOY OF WIRES: AN INTRODUCTION TO NETDUINO, .NET

MICRO FRAMEWORK AND THE INTERNET OF THINGS

Iain Angus

AGENDA Introduction• .NET MicroFramework• Internet of Things• Netduino

Getting started Setup, Fritzing, Breadboards

Building Blocks Digital Input / Output Analog Input / Analog Output (Pulse Width Modulation)

Displaying Data HD44780, Bar Graph

Communicating with Digital Sensors I2C / SPI

Internet Enabled Applications ThingSpeak

EVERYTHING STARTS SOMEWHERE…

Why Netduino…

• Visual Studio IDE• Step by step debugging• Reuse existing skills• Low cost electronics• Fast prototyping

THE DEVICES CONTINUUMDe

vice

Cap

abili

ties

Full

Limited

LargeSmall Device Category

Windows Embedded Compact

Windows Embedded

.NET MicroFramework

.NET Framework

MCU Example: ARM7 / Cortex-M3 / SH2 ARM9 / Cortex-A8 ARM11 / Cortex-A9 / Atom Centrino

THE NETMF OPEN SOURCE PROJECT

Smallest .NET implementation Targets small 32 bit processors (ARM 7-9, Cortex M(x), Analog Devices Blackfin, Renesas SH2)

Currently used in consumer products, industrial automation, energy management, health/eldercare, and lots of new categories.

First Open Source release – Nov 2009 Apache 2.0

Community based model Motivation

Avoid fragmentation Develop a clear collaborative direction

Core Tech Team Microsoft Development Team netmf.codeplex.com netmf.com

 Feature Required C# Compiler

.NET Micro Framework

Required Framework Features

Generics 2.0 no Generics

Nullables 2.0 no Generics, Nullable<>

Expression trees 3.0 no Generics, Expression<>

Anonymous types 3.0 no Generics, StringBuilder

Dynamic lookup 4.0 no Generics, CallSite, Binder

Variance in generic types 4.0 no Generics

FEATURES NOT AVAILABLE IN .NET MICROFRAMEWORK

THE NETMF VERSION 4.2From Microsoft Resources:

VB.NET (a collaboration) Cryptographic Primitives and Object Model Remote firmware update IL Optimizations Bug fixes SNTP

From the community:

VB.NET (a collaboration) New Platform builder FTP – client (desktop compatible) and server (NETMF only)

Regular Expressions StringBuilder Type PWM and Analog/Digital Conversion Bug fixes Secure Hardware (SIM Card) drivers

WHAT IS THE INTERNET OF THINGS?

Oxford Dictionary (noun): “A proposed development of the Internet in which everyday objects have network connectivity, allowing them to send and receive data”

Or… Computers, sensors and actuators connected through Internet protocols that measure or manipulate physical properties

INTERNET OF THINGS Current Key Applications: Smart grid and energy management: utility companies can optimize delivery of energy to homes and businesses while customers can better manage energy usage.

Home and building automation: Smart homes and buildings have centralized control over virtually any device or system in a home or office, from appliances to PEV’s security systems.

Asset tracking: Enterprises, hospitals, factories and other large organizations can accurately track the locations of high-value equipment, patients, vehicles, and so on.

Health and wellness: Doctors can remotely monitor patients’ health while people can track the progress of fitness routines.

WHAT IS NETDUINO? Made Secret Labs LLC Open Source Hardware Platform

.NET MicroFramework Family of products: Netduino 1, 1 plus, 2, 2 plus, mini Netduino Go

NETDUINO PROJECTS Netduino projects consist of up to three types of components:

•Actuators – things that do stuff (act)•Sensors – things that measure (sense)•Microchips – specialised functions

Allowing you to do prototyping, robotics, automation, automotive, sequencing as well as a learning aid

GETTING STARTED

DEVELOPMENT ENVIRONMENT

• Netduino 2 or 2 plus• Visual Studio 2010/2012• .NET Micro Framework SDK

v4.2• Netduino SDK v4.2.2.0 (32-

bit) or Netduino SDK v4.2.2.0 (64-bit)

NETDUINO PLUS 2 - ON THE BOARDLEDButtonSD cardEthernet

THE BREADBOARDA breadboard lets you wire electronic components without any soldering

Its holes are connected“under the hood” as shown here

FRITZING

BUILDING BLOCKS

GENERAL PURPOSE INPUT OUTPUT (GPIO) Digital input / output - logical 0 or 1

InputPort (Pin, Boolean, ResistorMode)• Read

OutputPort (Pin, Boolean, Boolean, ResistorMode)•Write

InterruptPort (Pin, Boolean, ResistorMode, InterruptMode)• OnInterrupt

DEMO – PUSH THE BUTTONComponents used:

NetduinoPush Button220 ohm resistor x 2LED

ANALOG INPUTPorts A0-A5 NetduinoAble to provide own reference voltage (Aref)10 bit ADC, value between 0 and 1023 if using SecretLabs implementation

12 bit ADC, value between 0 and 4095 if using Microsoft.SPOT implementation

Two implementations of AnalogInput class:

SecretLabsvar sensorPort = new AnalogInput(Pins.GPIO_PIN_A0);int rawValue = sensorPort.Read(); // returns count

Microsoft.SPOTvar sensorPort = new AnalogInput(AnalogChannels.ANALOG_PIN_A0);float volts = sensorPort.Read(); // returns % max voltageint rawValue = sensorPort.ReadRaw() // returns count

May need to translate reading into meaningful value, requires reading device datasheet…

ADXL335 ACCELEROMETER ANALOG SENSOR• Sensor has a full sensing range of +/-3g – zero G approximately 1.65V with Aref 3.3V• No on-board regulation, provided power should be between 1.8 and 3.6VDC• 330 mV/G

SecretLabs implementation:330 mV/G × (1023 ADC units) / 3300 mV = 102.3 (ADC units)/G

Microsoft SPOT implementation:330 mV/G × (4095 ADC units) / 3300 mV = 409.5 (ADC units)/G

ANALOG OUTPUT (PULSE WIDTH MODULATION (PWM))

• Digital I/O Ports 5&6, 9&10• Computers can’t output analog

voltages• Only digital voltages (0 volts or

3.3V)• But you can fake it if you

average a digital signal flipping between two voltages.

• Used everywhere• Lamp dimmers, motor speed

control, power supplies, noise making

• Three characteristics of PWM signals• Pulse width range (min/max)• Pulse period

(= 1/pulses per second)• Voltage levels

(0-3.3V, for instance)

DEMO – WORKING WITH ANALOG SIGNALS

Components used:

NetduinoADXL335 AccelerometerLED220 ohm resistor

ARE ALL PINS EQUAL?

power and i/oinput: 7.5 - 12.0 VDC or USB poweredoutput: 5 VDC and 3.3 VDC regulateddigital i/o are 3.3 V--but 5 V tolerant

DISPLAYING DATA

DISPLAYING DATA

LCD Display

LED Bar Graph

Seven Segment Display

LED

LED Matrix

Colour Display

DEMO – HD44780Components used:

NetduinoHD44780Potentiometer

In the animation to the below, we can see how the four-bit binary number 1001 is shifted to the Q outputs of the register.

SERIAL IN - PARALLEL OUT SHIFT REGISTERS

Shift register is controlled with three pins. They are usually called DATA, LATCH and CLOCK

Each time CLOCK goes high two things happen:• Current value in register shifted left by one,

last bit is dropped out• 1st bit set to current value of DATA

To write a byte to shift register this has to happen eight times in a loop

To update output pins you must pull LATCH high, data transfer happens on transition from low to high. This is also called rising edge

DEMO – NEVER ENOUGH PINS… 74HC595 SHIFT REGISTER

Components used:

NetduinoElectret microphone74HC595 shift registerLED bar220 ohm resistor

DIGITAL SENSOR

DIGITAL SENSORS Inter-Integrated Circuit (I2C)• 2 wire bus (SDA/SCL)• Devices are uniquely addressable• Relatively slow

Serial Peripheral Interface Bus (SPI)• 4 wire bus (SCLK/MOSI/MISO/CS)• Fast

touch sensor

compass

fm transmitter

temperature & humidity sensor

And many others..

HMC6352 DATASHEET

Command Byte ASCII (hex)

Response 1 Byte (binary)

Response 2 Byte (binary)

Description

S (53) SleepW (57) WakeupO (4F) S/R NowC (43) Enter user

calibration modeE (45) Exit user

calibration modeL (4C) Save Op Mode to

EEPROMA (41) MSB Data LSB Data Get data,

compensate, calculate new heading

I2C slave address :0x42(7 MSB with LSB 0 filled)

Heading mode:0 – 3599 binary format over two bytes (Tenths of a degree)

e.g. MSB: 0x0B LSB: 0x7F 0x0B7F = 2943 decimalDegrees: 294.3

Interface Commands / Responses

DEMO – I2C / SPIComponents used:

NetduinoNokia 5110 LCDDS1037 Breakout BoardHMC6352

CONNECTING TO THE INTERNET

CONNECTING TO THE INTERNETEthernet (built-in or shield), plug it in anywhereWifi (module), configured once per locationGSM/GPRS (module), configured once, easy to use

Bluetooth (module), via GSM/GPRS/Wifi of phoneZigBee (module), via ZigBee gatewayUSB (built-in), via desktop computer

IOT INFRASTRUCTURE SERVICES

Thingspeak, an open source "Xively", Twitter for devicese.g. https://thingspeak.com/channels/9

Xively (was Cosm, was Pachube), to store and reuse sensor measurementse.g. https://xively.com/feeds/116340

Twitter, allows objects to talk to humans or receive commandse.g. @twrbrdg_itself (f.k.a. @towerbridge)

Yaler, enables remote access to Internet-connected devicese.g. http://try.yaler.net/~arduino/led

ioBridgehttp://www.iobridge.com (https://realtime.io)

THINGSPEAK•Open Source API•Real-time data collection•Data processing•Data visualizations•Location-awareness•Status context•Application infrastructure•Twitter proxy•Apps•Plugins

DEMO ARCHITECTURE

Sensor Actuator

HTTP://PUT HTTP://GETapi.thingspeak.com

HTTP://POST HTTP://GET

ALTERATIVE ARCHITECTURE

Sensor as Server Actuator as Server

HTTP://GET HTTP://POST

api.thingspeak.com

DEMO – CONNECTING TO THE CLOUD

Components used:

NetduinoTMP36Hitec HS-422 Servo

USEFUL RESOURCESSecret Labs LLC http://netduino.com Forums http://forums.netduino.com Community Development Site for the .NET Micro Framework http://www.netmf.com API Reference for .NET Micro Framework http://msdn.microsoft.com/en-us/library/bb417054.aspx Adafruit http://learn.adafruit.com Sparkfun https://www.sparkfun.com/tutorials

AGENT SMARTWATCH - .NET ON YOUR WRIST

Kickstarter Funded – over $1million

• 120MHz ARM Cortex-M4 processor• with secondary AVR co-processor• 1.28" Memory Display (128 x 128)• with intelligent backlighting• Anti-glare glass lens• Bluetooth 4.0 BD/EDR + LE• 3-axis accelerometer• Ambient light sensor• Vibration motor• Qi wireless charging• Water resistant (ATMs: TBD)• AGENT OS 1.0 including .NET Micro

Framework 4.3

THANKS FOR LISTENING… AND QUESTIONS?