Editing Introduction (section)

== The ports ==

Smart Box has a number of different sockets which are used for the external connections.
These are divided into two types, the sensor ports and the output ports.
The sensor ports are used to measure external signals.
Smart Box can handle both analogue and digital sensors.
Analogue sensors produce a signal which can vary continuously and sometimes very rapidly, for example the signal from a sound sensor can change several thousand times every second whereas a temperature sensor may change relatively slowly.
Smart Box can also be used with digital sensors.
These will only switch on or off.
A pressure mat or a thermostat which switches at a preset temperature are examples of digital sensors.

The output ports are used to switch on and off external devices such as lamps and motors.
The 8 ‘Digital Outputs’ can each be used to switch on or off a low power device such as a buzzer or lamp.
The motor outputs have a greater power capability and can also be used to drive a DC motor forward and reverse.