If you are looking for the Chapter 9 content for the 2nd Edition of Exploring Arduino, please click here.

The SPI Bus

Parts List

• Arduino Uno
• USB A-B Cable
• Red LED
• Yellow LED
• Green LED
• Blue LED
• 100Ω Resistors (x4)
• Speaker
• Jumper Wires
• Breadboard
• MCP4231 Digital SPI Potentiometer (x2)

Code

Download Code (1st Edition, Chapter 9)
(Also available on GitHub)

Useful Links

• Arduino SPI Library Reference
• MCP4231 Datasheet (PDF)

Notes

If you’re unable to obtain the MCP4231 Digital SPI potentiometer in your country, you can also use the MCP4151 and leave the MISO line disconnected.

Color Wiring Diagrams

Chapter 9, Figure 6

Chapter 9, Figure 7

Videos

Follow along with this video for a visual tutorial about the SPI Bus:

Watch a demo of the SPI digital potentiometer color adjuster created in the chapter:

Watch a demo of the audiovisual platform created in the chapter: