HP 2000 - Manual (Page 34)

32
Loop Back Connectors
In order to run the RS232 serial port or parallel port self-test, a loop back connector is needed.
The loop back may be placed on either the OmniBook port or at the end of the corresponding
cable. This feature is also helpful in diagnosing a defective serial or parallel cable.
Loop back connectors may be purchased or easily constructed. The following illustrations
identify the correct pin-out configurations for the serial and parallel loop back connectors.
Figure 9 - Serial Loop Back Connector
Figure 10 - Parallel Loop Back Connector