This chapter commenced with a quick overview of the basic tools and equipment that you will need as you get further into electronics and the circuits that we will cover in Section 3 (which we'll be commencing in the next chapter). Then, we went through some suggestions to help keep your Raspberry Pi safe while you are connecting electronics to its GPIO pins, as well as a few tips when it comes to purchasing components.
Then, we explored Ohm's Law (and very briefly Kirchhoff's) before working through the reasons and calculations as to why our LED circuit was using a 200 Ohm resistor. We followed this example by looking at the electronic properties of digital circuits, where we explored logic voltage levels, floating pins, and pull-up and pull-down resistors. We then looked at analog circuits and worked through an example of a voltage divider circuit. We concluded this chapter by looking at logic-level conversion and how you can interface a 5-volt logic device...