Eia RS232 and RS422 Wrap Plug Test and Differentiation
Original Publication Date: 1986-Aug-01
Included in the Prior Art Database: 2005-Mar-09
Shorting or wrap plug connectors are often used with data communications devices to check operability of transmission and reception facilities by connecting output to input during a test. The plugs are manually installed and are normally removed when the device is ready for service. This article describes a technique of providing shorting contacts in a test plug for the RS232 standard pin connector interface that enable the machine being tested to detect the presence of a plug, the identity of the type of plug installed since both RS232C and RS422 connector plugs will fit the same connections, and also provides an LED (light-emitting diode) light signal output that can be used for showing proper operability of the circuit.