There are various ways to connect Scratch to the physical world, including Makey Makey, LEGO® WeDo, Raspberry Pi, and PicoBoard. Even though all of these devices require add-on hardware to interact with Scratch, they extend the Scratch experience and enable Scratch projects to connect to the physical world.
We're going to use the PicoBoard as the basis for our examples, because it tends to be one of the most popular devices used with Scratch and has a long history with the Scratch team. With slight modifications, each project can be adapted to work without a PicoBoard, and therefore, to work with Scratch 2.0.
In this appendix, I will introduce the PicoBoard and show you how to:
Animate webcam images based on detected sound
Monitor and collect environmental data and then graph the results
Explore electrical resistance
As of the publication of this book update, Scratch 2.0 does not have full support for add-on hardware such as the PicoBoard; however, the Scratch team foresees full support at some point in 2014. Until Scratch 2.0 fully supports the PicoBoard, you may use Scratch 1.4 to complete these projects.
I've selected projects that have components that will apply to Scratch 2.0 right now, including the webcam, detecting sound, recording data at set intervals, and graphing. The fact that I choose to use the PicoBoard to develop these projects acknowledges the wealth of opportunity to extend Scratch. It's also a nod to Raspberry Pi users for whom Scratch 2.0 is not currently an option, but the PicoBoard works on the Pi.