Interface Basics:
The interface is intended to operate on distances of up to 15 meters. This is because any modem is possible to be near the terminal. Data rates are also restricted. The maximum data rates for RS-232C are 19.2 k baud or bits per second although slower rates are frequently used.
Connections
The RS-232C specification does not involve a description of the connector to be utilized. However, the most commonly utilized connector is the 25-pin D-type connector.