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From: wb8foz@mthvax.cs.miami.edu (David Lesher)
Newsgroups: comp.sys.ibm.pc.misc
Subject: Re: IBM PC parallel port -- bidirectional...
Message-ID: <1990Sep22.145313.1888@mthvax.cs.miami.edu>
Date: 22 Sep 90 14:53:13 GMT
References: <4576@crash.cts.com>
Reply-To: wb8foz@mthvax.cs.miami.edu (David Lesher)
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Organization: NRK Clinic for habitual NetNews Abusers
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Reply-To: wb8foz@mthvax.cs.miami.edu (David Lesher)

Note that the genuine IBM XT parallel port would not read data on the 8
data bit lines.  There was (for some reason) a missing jumper between
the control decoder and the enable line on the driver chip, or
something equally trivial. With that installed, it would read just
fine, thank you. It's been a while since I changed a board to do this,
so I might have not remembered it exactly, but it was easy to see from
the print, and I think even the holes for the jumper were there for
you.

Note 1)	Stock boards would read the status lines. So if you only
need one or two bits, you can use the paper_out, etc.

Note 2) 99&44/100 of the clone boards were built correctly to
begin with.

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