Bidirectional is a communications mode transmits data in both directions (send and receive), but not at the same time. Bi-di (bidirectional) is also a printer port mode that was first introduced by IBM in 1987 with their introduction of the PS/2 computer.

The bidirectional port is an 8-bit port capable of transmitting between 75 and 300 KBps. It was available as either a type 1 or type 3 port, which used a DMA.

Parallel port, Printer terms, Unidirectional

  • How to change the LPT port within CMOS.
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