In the next challenge, we’re going to start hacking some open source hardware called Ardiuno. If you have not completed Challenge 0.6 Open Source Hardware (10/5 HW), you might want to do that first so you know what this is all about.
In Ubuntu Linux, locate the terminal emulator in the application panel. Open it.
The terminal display should look familiar to you. It's just like the Chrosh window from when you were installing Crouton.
We will now use the Advanced Package Tool or
apt to locate, download and install the Arduino Integrated Development Environment
IDE software from the Ubuntu repository server (e.g. on the internet) and install the package
arduino on our machines!
sudo apt-get install gcc-avr avr-libc openjdk-6-jre arduino git
In this step, you are instructing the
apt program to download the
git programs from the Ubuntu repository. Then you're also instructing it to install those programs on your computer… which should be happening right now on your screen. These are all very important programs for open hardware hacking!
The first two:
ave-libc are called “compilers” and they do important work in translating the human readable code that you type with words and symbols into the stuff machines can understand – the 0’s and 1’s.
The next one,
openjdk-6-jre, is a special program that helps to process graphics, which will be important for the one after it:
arduino. This is the program we will use to talk to the
Arduino. The last program,
git is a special one that we will use to share and save our work. Think of it as Google Docs for hackers… we’ll make more sense of that later.
Finally, the command
sudo stands for “superuser do”. Every user on a computer has permission to change their own files. Some users have permission to change their files and other people’s files (like a system administrator… the computer guy at work or school). For example, sometimes your parents will put locks on your computer to prevent you from using it in ways they don’t like. They are special users.
A superuser has permission to do anything and can make the computer do anything! Now do you get the cartoon?
A new window should open. It should look like this:
OK, you’re almost ready to connect up the Arduino hardware board and get hacking, just one more step...
The sudo command doesn’t really make you the superuser, it just lets you pretend to be the superuser when you type and only when you type it. You have to type it every single time you want to *force* the computer to do something. You don’t want to always be forcing the computer cause you’ll be busy doing other stuff. So we’re going to change some of your permissions for good.
First, your computer talks to the Arduino board using the USB, which stands for Universal Serial Bus. It’s a certain type of connector that uses
Serial communications! Serial communications are A LOT like telephones and your computer will want to
dialout to the Arduino (thats why you got that error message). We have to make sure that you have permission to
dialout by adding your
username to the
sudo usermod -a -G dialout stemscholar
Good, now you can
dialout… to continue with this challenge, you will now need to get:
Plug the square end of the USB into the Arduino board and the flat rectangular end of it into the USB
port on your Chromebook.
The next step is to open up the "phone lines". The USB plugs into a
port and each
port on your computer has a special code. The USB
port is called
ttyACM0 (thats a zero at the end!). We’re gonna give you permission to talk through this
sudo chmod a+rw /dev/ttyACM0
This is telling the computer to “change mode”
a-all (everyone) to be able to
w-write on the “device”
/dev connected to the
Alright! You now have permission to
dialout to the Arduino on the USB port