2.0 - Arduino Code
Lets make an LED blink!
For this project all we need is an UNO board, a usb cable, and the IDE. This mini project will get you oriented to the UNO, the IDE, and the code that makes it do stuff.
IDE = Integrated Development Environment = an application that allows you to edit/write code, compile it, and send it to Arduino devices.
2.1 - First Arduino program
-
Open Arduino Software IDE.
-
Click
File
>Examples
>01.Basics
>Blink
. This will open a new window with the Blink program. These built in examples are a great way to learn. You don’t need to write code from scratch: borrow. That is the power of code!Sketches are programs written using the Arduino IDE. Each is saved in its own folder and has the extension .ino.
- Take a first look at the code:
//
means the line is a comment. The computer will ignore it - humans only! Multiple line comments are enclosed between/*
and*/
. For example,/* this is a comment */
- Each Arduino program is made of two functions,
setup()
andloop()
. Code in thesetup()
runs one time when the board starts up. Next, code in theloop()
runs and then repeats until you pull out the plug!
-
Plug your usb cable into your UNO and computer.
-
On IDE, click
Tools
>Board
>Arduino/Genuino UNO
to set up the correct board. -
Click
Tools
>Port
and select the port where your UNO appears. -
Click the
Upload
arrow icon. The IDE will verify, compile, and upload your program to the UNO. Any errors will appear in the console window below the text editor. - Take a closer look at
Blink
:pinMode()
is a set up function that tells our board to use a specific pin as an output or input.LED_BUILTIN
is a special variable that refers to a LED built in to a board.digitalWrite()
is like a switch:HIGH
= on,LOW
= off.delay()
is a timer that make the program wait. The delay is given in milliseconds.
- Mod this code! Change the delay times or add more on/off’s, then click the upload arrow to get it running on your board. Congrats: you are a programmer!
More info: The Arduino IDE is based on the “sketchbook” created for Processing and Wiring, platforms originally designed for creating interactive projects in the visual arts. The Arduino programming language is really a set of libraries in C and C++. Arduino IDE hides some of the complexity of setting up, but be proud that you are writing C/C++ code!