In this chapter, we saw how we can attach analog sensors to our Pi Zero with the use of an ADC, and how we can add 5V sensors to our 3.3V Pi Zero with the use of a simple resistor-based voltage divider. We have also gone a bit further with our use of the Scroll pHAT HD by creating two different areas on our display, which update at different intervals.
The program for monitoring our heart rate introduces some more advanced mathematics to keep a track of the high and low pulses of our sensor, tracking the time between them, and calculating the average of a set of ten of these beats to calculate our BPM.
You can see a video of my completed heart rate monitor at https://www.youtube.com/watch?v=CaQMu6f1UJ8
In our next and final chapter, we will create our own GPS tracker, which we can use to log where and how far we move, while we are out and about!
