Path: utzoo!attcan!uunet!ginosko!gem.mps.ohio-state.edu!tut.cis.ohio-state.edu!att!cbnewsl!raj
From: raj@cbnewsl.ATT.COM (Richard A. Johnson)
Newsgroups: comp.unix.i386
Subject: Parallel I/O Port
Message-ID: <1609@cbnewsl.ATT.COM>
Date: 24 Aug 89 17:26:47 GMT
Organization: AT&T Bell Laboratories
Lines: 19


I have an AT&T 6386 WGS running UNIX.  I want to use the parallel I/O
port to communicate with devices other than printers.  One example
would be to connect 2 PCs together using the parallel port on each PC.

According to the man page for lp(7), "The parallel port behaves as
described in termio(7)."  From this I would assume that I can do what
I want to do, but I don't know how I need to connect the physical ports
together.  I tried 25-pin ribbon cables, and ran "cat /dev/lp" on one
PC, and "date > /dev/lp" on the other, but both commands hung.

Does anybody know how to do this?  I was thinking that perhaps I need
to switch some of the signals around in the connection, somwhat like
an RS232 null-modem connector.  Please send me mail if you can help.

Rich Johnson
AT&T Bell Labs
Whippany, NJ
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