Now that we have our Raspberry Pi 3 up and running we can start with our first project that uses it. In this chapter, we will be doing presence detection using the integrated Bluetooth chip and show it on a HD44780 16x2 display. As only showing presence will not fill the whole display, we will be adding light intensity detection and environmental temperature. We would also like to add a home automation factor to this setup by adding a relay that can turn on a light. This little project could possibly be placed at a strategic location such as an entry hallway on which we will focus.

We would like to turn on a light switch when we're nearly home when the light in the hallway is quite dim and show the current temperature. This chapter will then cover the basics of using libraries in other projects in the book.

To be able to build this, we will be covering the following...