If you are looking for the Chapter 2 content for the 2nd Edition of Exploring Arduino, please click here.

Digital Inputs, Outputs, and Pulse-Width Modulation

Parts List

• Arduino Uno
• USB A-B Cable
• Small Breadboard
• Jumper Wires
• 10kΩ resistor
• 220Ω resistor (x3)
• Pushbutton
• Red LED
• Common-cathode RGB LED

Code

Download Code (1st Edition, Chapter 2)
(Also available on GitHub)

Useful Links

• Arduino setup() Reference Page
• Arduino loop() Reference Page
• Arduino pinMode() Reference Page
• Arduino digitalWrite() Reference Page
• Arduino analogWrite() Reference Page
• Arduino constants Reference Page
• Arduino for loop Reference Page
• Arduino delay() Reference Page
• Arduino digitalRead() Reference Page
• Arduino if/else Reference Page

Errata

Code errata listed below are corrected in the code downloads available from this page, and from github.

• In numbered list on pages 26 and 27, there should be another step between steps 1 and 2: “100 is less than or equal to 1000, so the loop contents execute.” This makes the for loop description more clear.
• In code listing 2-5, there is a missing closing bracket ( } ) following the “current = digitalRead(BUTTON);” line in early prints of the book. This has been fixed in later printings.
• In code listing 2-6, the “if” statement for Purple should be an “if else” statement.

Color Wiring Diagrams

Chapter 2, Figure 2

Chapter 2, Figure 5

Chapter 2, Figure 7

Videos

This video will teach you about digital inputs/outputs, debouncing, and PWM:

This video will teach you the basics of electrical and computer engineering: