Sensor
<hardware> An electronic device used to measure a physical quantity such as temperature, pressure or loudness and convert it into an electronic signal of some kind (e.g a voltage). Sensors are normally components of some larger electronic system such as a computer control and/or measurement system.
Analog sensors most often produce a voltage proportional to the measured quantity.
The signal must be converted to digital form with a
ADC before the CPU can process it.
Digital sensors most often use serial communication such as
EIA-232 to return information directly to the controller or computer through a
serial port.
