The majority of the demo programs in this book use external hardware that must be purchased separately. Each time a demo program is given, which requires additional parts, they will be listed by part number and/or description. We will do our best to use the most readily available and lowest cost parts. All of the parts used can be purchased from one or more of the following resources:
SparkFun: https://www.sparkfun.com/
Adafruit Industries: http://www.adafruit.com/
Digi-Key: http://www.digikey.com/
Mouser: http://www.mouser.com/
Farnell / Newark / Element14: http://www.farnell.com/
The circuits in each demo will be assembled using solderless breadboard and jumper wires. Both come in many different shapes and sizes.
Breadboards and jumper wires can be purchased from any of the preceding links, and you'll probably want to start out with one standard-sized breadboard and a jumper wire kit, such as that from Adafruit:
Breadboard: http://www.adafruit.com/products/239
Jumper wires: http://www.adafruit.com/products/153
That should provide enough breadboard space and jumper wires to assemble most, if not all, of the demo circuits in this book.
Just like with software, it is inevitable when assembling hardware that things won't always work the first time. There are many tools that can greatly reduce the time it takes to fix these problems. The most useful for the circuits in this book will be a multimeter, which is a tool that measures voltage and current, and often additional properties such as resistance, capacitance, and frequency. Both SparkFun and Adafruit carry very affordable digital multimeters. While these are not high quality measurement tools, they are certainly suitable for these circuits. Though not essential, I would highly recommend having some sort of multimeter on hand when building the circuits in this book.
More helpful than a multimeter for debugging tools such as PWM and serial protocols is an oscilloscope, which shows you a plot of voltage over time to visualize many different signals in a circuit. This is a more expensive tool, and will be less necessary for these circuits. Throughout the book, however, you will see screen captures of an oscilloscope to show various signals, and it should become evident just how helpful they can be. Again, Adafruit and SparkFun carry affordable oscilloscopes.
