[MUSIC]

Hi I'm Chris Continanza, I'm here to talk to you

about the Internet of Things and keep you from lunch.

>> Woo.

>> So that's my honor.

So what I wanted to show you was a thing connected to the Internet.

So everyone on this side who cannot see, this is an LED matrix display board.

This is basically six pieces and you can buy each of these

as a three by two matrix and they are daisy chained together.

But the important part of this thing is that

it's connected to the Web and yeah, so things.

So things essentially when we talk about

Internet of Things we really mean computers.

And the change has been that the computers have obviously

shrunk in size and increased in processing power thanks to Moore's Law.

Because of that we're able to get logic in places we couldn't before.

And now we're, you know, able to I kind of

developed this whole new generation

of devices and basically real-world interactions.

That's kind of what I care about.

And so you have the real world interaction side.

And then you might say hey, you know, I have this device,

I've coded it up to do some cool stuff, but I'd really like

it to be infinitely dynamic or configurable

from where I am sitting at home.

And that's where the Internet is gonna kind of come

in or make something that's automatic or based off of data.

These slides are really here to kind of guide those stuff.

So I, actually I could use maybe this, this one to show the things.

So, as, as the things come up.

Basically there is two kinds of

computation platforms you are gonna deal with.

there's, there's the tiny, tiny microprocessors and

there's something that's big enough to run Linux.

And so, in the world of tiny, we have Arduino.

We have our Spark, we have an Electric Imp this is an Embed from Arm,

which is a small M3 processor.

And then for Linux, here's your Raspberry Pi.

And, you know there's kind of this notion that eventually Linux will

make it small enough, but I actually think there's always gonna be a

leading edge of devices that are always gonna be a little bit

smaller, a little bit more efficient than something that can fully run Linux.

That's gonna matter to us in about

three minutes when we start talking about protocols.

Because one of the big advantages of having Linux

on board is you get to take advantage of the whole TCP/IP stack that comes with

Linux that we've all been programming on for, you know, the last x amount of years.

Actually raises a good point for a raise of hands.

Who does develop server side web software here?

Here, there, all right we're all in the club.

So, you know I'm from the same boat.

I got started with Arduino a couple of years ago.

Just kind of having fun on the side.

And actually my odyssey with Arduino and the Internet

began with a project called the Heroku Outage Lights.

I was in the office one day and somebody came up

to me and was like, hey Chris, I don't care what

kind of Arduino crazy thing you need to do, but when

our status site is red, I want the office to be red.

And so, this is actually as simple as kind of an Internet

of things application can get, because all this has to do is trip a relay.

So this is no more confusing on the hardware side than blinking an LED.

What it does on the software side is it pegs status.heroku.com

has a JSON Endpoint, so it just pings that on a loop.

And then whenever it says, oh the status is red, turn the relay on.

Getting this connected to the Internet was easy, because I was able to use Ethernet.

So this is the Ethernet shield Arduino,

and that was my first Internet-connected Arduino project.

It actually went really easy because I had the wire

I could just plug in, and be on with my life.

As soon as we go wireless things get a little bit more complicated.

All right, so things.

So the reason I have these things listed, Ardurino, Raspberry Pi, and

Ardurino Yun is that Arduino is a perfect example of a microprocessor.

This handles your interactions

with the real world, but doesn't, say actually connect

to the Internet itself, which is why you need an Ethernet shield, or this Adafruit.

This is the CC3000 chip, which we'll actually see packaged

up again in a smart device, also the same chip.

And you can buy one in this format, which is the same format as the XB.

XB as the WiFly. The Raspberry Pi itself actually has

Linux on it, so you don't need or has an Ethernet, rather.

It has its own TCP/IP stack so you don't have to rethink a lot of the world

but to make this WiFi enabled we still have to add our own WiFi chip.

And then something like the Arduino Yun is I don't have one yet, because

I haven't been able to get my hands on it, but that's actually kind

of these hybrid solutions where you have a Linux system, essentially handling all the

Internet side of things, and then an

Arduino handling all of your inputs and outputs.

These things start to get complicated when you say, I have GPIO

here, but I really like being able to do shields with an Arduino.

So you

can take a Raspberry Pi and then connect it to an Arduino and control it with

something like Cylon or Johnny 5 but, that tends to involve too many parts for me.

So the different ways to connect to the Internet with

a thing Ethernet, fun, easy, simple, but requires a wire.

And part of my personal challenge is Ethernet

ports are getting rarer. So Heroku moved to a new office.

It turned out that there were no Ethernet ports.

So I had all these fun Ethernet based applications

and I had to convert them all to WiFi.

And that itself kind of informed some of this experience.

So I kind of want to get to that story.

When you have different ways of connect to the Internet now.

So there's the Ethernet shield itself

XP is this format.

It's not this chip, but it looks very similar.

XPs allows you to do a mesh network.

So, XPs don't connect you to directly to the Internet itself.

But an XP will usually be a first hop to connect

you to perhaps a Raspberry Pi, that's connected to the Internet.

That CC3000 chip is just a very popular chip that is directly doing WiFi.

I found it hard to work with,

so I'm very excited to try out the Spark chip.

There's a library for using that in Arduino that isn't completely polished.

This project actually uses an Electric Imp.

So if I don't break it well what I have here is an Electric Imp Breakout Board.

And that is handling the WiFi and I'll talk to

how the WiFi communicates with the Arduino in a second.

>> And then the Yun, like I said is

actually an Arduino with a small lineno with a small distribution on it.

And basically you have Linux handling the

Internet and Arduino handling inputs and outputs.

So, this specific example, which I feel bad, because it's blocked and I don't have

enough surge protector, but what this is, is

the rea-, reason I chose Arduino is that

Arduino comes with a library that easily

connects to these LED matrix display boards.

So that was kind of a necessary, and it

was very simple when it was hooked up with Ethernet.

So then I tried to use the CC3000 chip, but

I actually wound up with a pin conflict, in that

this needed one of the interrupt pins on the Arduino,

pins two or three, and my LED matrix board also

wanted both pins two and three.

so, it kind of looked cool because you would just

have this random splat of LEDs turned on and off.

But there is no app name that is, you know, like, something dash splat.

So I met one of the guys from Zivley, and he said,

hey, can you use an Electric Imp to connect to the Internet.

So this is an Electric Imp. And what the Electric Imp is,

is it's an SD card format, but it has WiFi

in it. So to connect an Electric Imp to the

Internet you actually do this interesting thing where, you flash,

and not in the streaking sense, but in the more of the epilepsy sense.

So this, if you have problems with blinking, turn away now.

So this is actually how you communicate

the WiFi credentials onto the Electric Imp.

So that's kind of a pretty cool way of not having

to recompile the same program just because you changed your WiFi credentials.

Which I really liked about it cuz it lets me kind of take

this with me, go into another room, set it up in my Internet device.

So, part of the Internet of Things and connecting stuff

to the Internet means you're gonna have to talk protocols.

TCP/IP matters again.

So we don't have the advantage of having Linux running

for us and just opening up the connection to the web.

For some of these devices shipping your own TCP/IP stack,

specifically even with the embed actually becomes part of the equation.

And that's why I think

that, that does matter and what platform you choose will make a big difference.

Things like Spark and Imp are a lot more Internet ready.

Things like the CC3000 shield for Arduino and the embed

specifically are a little bit more lower level, and they ship with a bunch of

C++ code that you actually have to compile your own TCP/IP stack.

Which, you know, is something that we may or may not be familiar with or having fun.

There's always UDP around, don't wanna leave anybody out.

And then for actually application-level protocols, once we have a WiFi connection

or an Ethernet connection, once we're talking TCP/IP, we can actually finally

get back to the land we're familiar with HTTP, Websockets and then

MQTT up, it's up here because it actually fills, fills a need.

It's very easy to talk HTTP from these devices.

I actually wrote my own

rest client for Arduino, which worked great on the Ethernet shield.

Not so much for the WiFi shield cuz

it's a totally different hardware stack or software stack.

It's a different interface and my C++ chops are not so good with polymorphism.

I was trying to pass a void pointer

around, and apparently you're not allowed to do that.

So yeah, so with HTTP it's, it's still

really easy.

With WebSockets it's, way less fun of a protocol.

I've gotten projects going with WebSockets on

the Raspberry Pi because you can actually

compile you can run Node and take

advantage of stuff, stuff somebody else wrote.

And that's kind of where MQTT comes in, because MQTT is a

simpler protocol than Websockets, but fits

that same niche of real-time communication.

I think that's a different slide.

So, sorry, what I wanted to talk about was how this works, because it's kind

of an example of both the trials

and tribulations of building an Internet connected thing.

I really wanted it to do something.

So, wanting it to work was a big part of it.

The way this works now is there's an Arduino,

and the Arduino is connected via the Electric Imp

breakout board.

Now if you're gonna want to get something online

you are gonna have to have something like this layer.

You can directly, you know, from the Raspberry Pi talk to the GPIO pins.

So you don't have to have an Arduino per se, but if you do want to connect in

Arduino you're gonna have to have to use either

the Imp shield, the WiFi shield, or the Ethernet shield.

and, the reason I went with the Imp is because it allowed me to do a software

serial connection. So, I have the Imp is actually talking,

and I'll show this code, is talking via software serial to the Arduino itself.

So the Arduino sits there and it waits on

a serial connection from, so its deployer's Imp Serial.

And without getting too much into it

right here we set up a software serial that

I call Imp serial on pins eight and nine.

So the long story short there is I was

able to get around the requirement that the matrix display

board needed two pins by using the Imp board and

letting that speak software serial over pins eight and nine.

And the lesson there isn't that everyone should run out and

use software serial, it's that there's gonna be an annoying hiccup

somewhere in your project, and getting around it may not be straightforward.

So what I learned there was there's this protocol called UART.

And UART is actually built into the Imp. So the Imp is running in the Cloud

right here, and down here are these strings.

So has anyone figured out what, what this is actually displaying yet?

>> [INAUDIBLE] >> Close.

>> [LAUGH] Heroku Deploys. Heroku Deploys, exactly.

So people that are deploying to Heroku

right now every deploy is scrolling across this.

And the reason I built that is because

the outage lights was kind of a downer project.

It's only working when something bad's happening, and it has to be

working all the time so I put in effort to monitor it.

And to make sure that, you know, it was still checking

the requests and did all this

productionization for something that essentially sits in

the corner gathers dust and is good if it stays off all day.

So the idea behind this was how to I take

something that's happening un-visualized and visualize it in the real word.

And some of the initial ideas that came around were, hey, why don't we

blink an LED every time someone deploys, which is cool, but I figured would

have been very hard. I mean, this is blinking, right?

Like it's not really that impressive and there's kind of that a lot of

explanation you have to do like what is this thing blinking on your desk, why?

You know no one is really going to associate that with app names.

So I figured well, if I can figure out the name of the app while it's

being deployed it would be really cool to

get a lot of LED's together and display that.

And so that's kind of what

informed this project.

And then some other things that I've worked on with Heroku has

been like a demo of Websockets talking to a back-end Heroku app.

but, you know, that was that's actually where we found out that Socket IO

doesn't really like to open lots and lots of connections and other, other issues.

But,

anyways the idea behind this is that there's a backing Heroku app, and so

there's also a whole server side component

where this is subscribed to an event stream.

And originally events were coming in the events stream

and this would pull itself over a GET request.

But the Electric Imp actually runs a server side thing, so

I had to change that to every three deploys it posts to

an endpoint in Imp land.

And then that like unique URL then sends the data down to the Imp.

Which writes it over UART software serial to the Arduino, which can then read

the characters and say, ha, I found a comma I will now print the name.

So, part of the Internet Side of Things is you

might have questions about should I use Ruby or JavaScript?

Should I use

Postgres or Redis? Should I post on Amazon or Heroku?

How am I gonna operate this thing? This is where I spend my whole day.

So, I'm happy to help people with questions like that, and how they want

to set up the server side, and the Internet connection for their app.

And, that's it, thank you. [SOUND]