Chapter 4. Getting started with embedded systems
This chapter covers
- Understanding the various categories of embedded systems
- An introduction to working with the Raspberry Pi
- An introduction to setting up and using Node.js for IoT prototyping
- Learning to connect sensors and actuators using GPIOs
As we discussed before, there are two broad categories of physical objects on the Web of Things: tagged objects and connected objects. The first category comprises various tagging technologies that are attached to a product, such as barcodes, QR codes, NFC or RFID tags, and so on. In this case, objects aren’t connected directly to the web, only passively, because there’s a need for another device or application to interact with the product. Connected objects are directly connected to the Web of Things and are the world of embedded systems and embedded devices, which are essentially small, relatively inexpensive, low-power computers with limited resources and capabilities. You can apply the techniques and architecture you’ll learn about in this book to both tagged and connected objects, but the focus of this book is mainly on connected objects.
In chapter 2, you learned how to consume services from a real embedded device—a Raspberry Pi located in our office—to get a first glimpse of the Web of Things. But this wasn’t very physical because the device you interacted with was neither yours nor next to you.