In this chapter, we learned how to measure temperature and humidity using the common DHT11 and/or DHT22 sensors. We also looked at how to use an LDR to detect light, and this allowed us to explore voltage divider circuits and ADCs in greater detail. We concluded by retrofitting our LDR circuit so that we could detect moisture.
The example circuits and code we covered in this chapter provide practical examples of measuring environmental conditions with readily available sensors and simple circuits. Your understanding of these sensors and circuits now means you can adapt the examples for your own environmental monitoring projects, including using them as input triggers together with Python to control other circuits.
We also saw new practical applications of voltage divider circuits and how they are used in analog circuits to turn variable resistance into a variable voltage for use with an ADC. These examples and your understanding of them represent an important skill that you...
