An analog signal is a change in voltage over time.
A digital signal is a voltage that is set to on or off over time.
The record player is analog and the CD player is digital.
Here is a list of some sensors and the interfacing type.
- Grove moister sensor
- Grove air quality sensor
- Grove infrared reflector sensor
- Grove LED
What are digital signals used for?
The digital I/O (input/output) ports on the RPi the can be set to read an input high or low or output a high or low signal.
An example of an output is to set the port high to turn on an LED or a relay.
An example of a relay is shown here;