Reading analogue signals is very useful in a multitude of applications. For example many sensors output an analogue signal that is proportional to the stimuli being measured like temperature, light, pressure and sound level.
The Raspberry Pi GPIO does not have any Analogue to Digital Converters (ADC) to allow this to be measured directly. The projects in this book are all about using an external ADC and then interfacing to a number of sensors to make measurements.
Project 1 – Measuring Voltage
Project 2 - Temperature measurement using the TMP36
Project 3 – Resistance Measurement
Project 4 - Measuring Temperature using a Thermistor
Project 5 - Measuring Light Level using a Light Dependent Resistor
Project 6 – Measuring Force using a Force Sensing Resistor
Project 7 - Measuring Voltage of a Car Battery
Project 8 – Measuring Low Voltages
Project 9 - Measuring Power Using a Current Clamp
Project 10 - Measuring Sound Level Using a Microphone