[Feb 2016] A Special Webinar for Forward4

Internet of Things 101: Building IoT Prototypes w/ Raspberry Pi

Tomomi Imura (@girlie_mac)

Tomomi (@girlie_mac)

● Lead Dev Evangelist at PubNub

● Front-End Dev

● ❤ Hardware hacking

● Cat Lady of the InterWeb

What You Will Learn Today

1. Internet of Things and Data Stream

2. How to send & receive data with PubNub using Python

3. How to wire a LED & resistor to Pi using breadboard

4. How to program Pi to blink the LED

5. Making it IoT : Remote-controlled LED from web interface

Era of Internet of Things

Source: PLATFORM, data based on Cisco IBSG

Estimate 50B by 2020non-human/human = 6.58

2003: non-human/human = 0.08

2015: non-human/human = 3.47

2008: non-human/human >= 1

Withings: Smart Body Analyzer

GE Link

Cinder Sensing Cooker

Nest: Learning Thermostat

Whistle: Connected pet collar

Amazon Dash Button

Smart Devices

Smart-Ass Devices :-D

Internet of Things

………

Bluetooth

Internet of Things with Data Stream

Send & Receive Data to/from Data Center via Internet

PubNub Data Stream

Two-way communication to/from every device in the world.

https://pubnub.com

Realtime Reliable Secure

PubNub is globally distributed realtime data stream network (DNS)

PubNub Use-Cases

◼ Chat (Periscope)

◼ Multi-player games (DeNA games)

◼ Vehicle Location Tracking (Lyft, GetTaxi)

◼ Financial data (TD Ameritrade)

◼ Collaborative teaching tools (ClassDojo, CodePen)

◼ IoT, Smart Home (Insteon, Logitech)

Prototyping Internet of Things

Send & Receive Data to/from Data Center via Internet

LED

6. USB TO POWER SOURCE 5. TO MONITOR

4. TO MOUSE

3. TO KEYBOARD

2. WI-FI ADAPTER1. SD CARD

Getting Started with Raspberry Pi

https://github.com/pubnub/workshop-raspberrypi

Raspbian OS

SSH into your Rasp Pi

1. Get your Raspberry Pi’s IP address

pi@raspberrypi ~$ hostname -I

2. SSH to Pi from your laptop

(Terminal on Mac/Linux, PuTTY on Windows):

me@MyMac ~$ ssh pi@10.96.70.1

SSH into your Rasp Pi

Use your Pi’s IP!

Your Pi’s username

If SSH-ing fails, try:$ sudo raspi-config on your Pi

Programming Rasp Pi

Pre-installed on Raspberry Pi:

C / C++

Get Started w/ Python

Update your system first

~$ sudo apt-get update

~$ sudo apt-get upgrade

Install python and pip

~$ sudo apt-get install python-dev

~$ sudo apt-get install python-pip

Wut, you want Node.js?

~$ wget http://node-arm.herokuapp.com/node_latest_

armhf.deb

...but we’re using python today!

Don’t worry, I’m a JS dev too :-)

Installing PubNub

~$ sudo pip install pubnub

https://github.com/pubnub/workshop-raspberrypi/tree/master/projects-python/helloworld

Hello World w/ PubNub

Hello World w/ PubNub

Import & init (hello.py)

import sys

from pubnub import Pubnub

pubnub = Pubnub(publish_key='demo',

subscribe_key='demo')

Use your own publish & subscribe keys!

Hello World w/ PubNub

Publish (Sending data)

channel = 'hello-pi'

data = { 'username': 'Grumpy Cat',

'message': 'Hello world from Pi!'}

def callback(m):

print(m)

pubnub.publish(channel, data, callback=callback,

error=callback)

Hello World w/ PubNub

Run your program

~$ sudo python hello.py

Debug Console

http://pubnub.com/console/

1. channel: hello-pi

2. pub key: demo

3. sub key: demo

https://github.com/pubnub/workshop-raspberrypi/tree/master/projects-python/led

Hello World of Hardware:Blinking LED

1. Raspberry Pi 2 (w/ a WiFi Adapter for later exercise)

2. 1 Breadboard

3. 2 Male/Female jumper wires, 2 colors

4. 1 Resistor (200Ω)

5. 1 LED (1.9 - 3.2V)

What you need

OMG Physics!

Cathode (-) Anode (+)

- +

1.9V 3.2V

- +

OMG Physics!

R = V - Vs f

I

source voltage (V) forward voltage (V) (LED voltage drop)

current thru the LED (A)

resistance (Ω)

OMG Physics!

R = 3.3v - 1.9v

0.02 A

source voltage (V) forward voltage (V)(Red LED voltage drop)

current thru the LED (A)

resistance (Ω)

= 70 Ω

4-band Resistor Color Code

47 x 100 =

4.7 k Ohms

4 7 102 +/- 5%

multipliertolerance

Learn more at: https://learn.adafruit.com/multimeters/resistance

5-band Resistor Color Code

200 x 1 =

200 Ohms

2 0 100 +/- 1%

multipliertolerance

Learn more at: https://learn.adafruit.com/multimeters/resistance

0

Breadboard

400-pinMini

We are using this kind today!You may find this type of breadboard when googling circuits. They have power rails that goes vertical!

not connected !

An electronics breadboard is a fundamental tool to build circuits. It is solderless, and great tool for prototyping.

conductive metal strips goes horizontally

Connected!

Turning LED on

3.3V (Raspberry Pi)

LED

Turning LED on

3.3V (Pin 1)

GND

Anode (longer leg)

Cathode

Raspberry Pi 2 Pins

3.3V

Ground

GPIO (general purpose input output)

Programming LED

GPIO-4 (Pin 7)

Programming LEDimport RPi.GPIO as GPIO

import time

GPIO.setmode(GPIO.BCM)

LED = 4

GPIO.setup(LED,GPIO.OUT)

for i in range(6):

GPIO.output(LED,True)

time.sleep(0.5)

GPIO.output(LED,False)

time.sleep(0.5)

import RPi.GPIO libs

set pin type. use BCM, not pin number

GPIO 4 pin (Pin 7)

set LED pin as output

toggle light pin signal to low/high to make it blink.

7 times.

https://github.com/pubnub/workshop-raspberrypi/tree/master/projects-python/remote-led

Making it IoT: Remote-Controlled LED

Making it IoT: Remote-Controlled LED

publish data subscribe data

Publishing data from a web client

var pubnub = PUBNUB.init({

subscribe_key: 'demo',

publish_key: 'demo'

});

button.addEventListener('click',

function(){

pubnub.publish(

{channel: 'disco',

message: {led: 1}}

);

});

Making it IoT: Remote-Controlled LED

When the button is clicked on browser, it publishes data, {‘led’: 1}

Subscribing data to Raspberry Pi

pubnub = Pubnub(publish_key='demo', subscribe_key='demo')

channel = 'disco'

def _callback(m, channel):

if m['led'] == 1:

for i in range(6):

GPIO.output(LED_PIN,True)

time.sleep(0.5)

GPIO.output(LED_PIN,False)

time.sleep(0.5)

pubnub.subscribe(channels=channel, callback=_callback, error=_error)

Making it IoT: Remote-Controlled LED

button.addEventListener('click', publish);

As soon as a message is published from a browser, the message is subscribed to Pi

Disco! http://pubnub.github.io/workshop-raspberrypi/web/disco.html

Making it IoT: Remote-Controlled LED

IoT & PubNubCase Study: Insteon

http://www.insteon.com

Data Visualization with Temperature Sensor

It uses a capacitive humidity sensor and a thermistor to

measure the surrounding air, and spits out a digital signal on

the data pin.

https://github.com/pubnub/workshop-raspberrypi/tree/master/projects-python/dht22

http://pubnub.github.io/workshop-raspberrypi/web/temperature.html

Realtime Data Graphs & Charts

https://github.com/pubnub/eon-chart

Resources

◼ Raspberry Pi - https://www.raspberrypi.org/

◼ PubNub - https://pubnub.com

◼ Step-by-step instructions & Code sample on GitHub -

https://github.com/pubnub/workshop-raspberrypi

◼ This slide deck: https://goo.gl/NHIkJe

Thank you :-)

Tomomi Imura (@girlie_mac)

https://www.pubnub.com/blog/author/tomomi/

http://girliemac.com

Tuts+ Node.js & Arduino tutorial: http://goo.gl/LTtPn4

Creative Commons Attributions

◼ LED circuit: Wikimedia

◼ GPIO Pins: RaspberryPi-Spy.co.uk

Also, great public domain images from Pixabay, and an

open-source software, Fritzing for circuit diagrams!