Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!cbmvax!valentin
From: valentin@cbmvax.commodore.com (Valentin Pepelea)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: Using the Parallel Port
Keywords: ppppppppport
Message-ID: <10293@cbmvax.commodore.com>
Date: 21 Mar 90 22:48:26 GMT
References: <3257@ssc-vax.UUCP>
Reply-To: valentin@cbmvax (Valentin Pepelea)
Organization: Commodore, West Chester, PA
Lines: 31

In article <3257@ssc-vax.UUCP> dano@ssc-vax.UUCP (Dan Olson) writes:
>
>1)  Is there anyway for a device on the parallel port to know
>whether it is being written to or read from with only a read or
>write to the 8520 port B?

I don't think so.

>2)  When acknowledge (FLAG pin) is pulsed, is it only used for 
>generating an interrupt, or will it also cause port B to latch 
>what's on its pins?

It merely generates an interrupt.

>For maximum compatability with AmigaOS I'd like to use the
>parallel.device for accessing my device.  Any insight on how it
>handles the parallel port would be appreciated.  I assume it reads
>or writes new bytes on acknowledge interrupts.  How fast can the
>parallel.device respond to an interrupt?

The 1.3 parallel.device reads and writes about 6000 bytes per second. The
tranfer is not biderectional. Matt Dillon came out with a parallel.device
replacement which allows two Amigas connected together to communicate
bidirectionally as if they were using the serial port.

Valentin
-- 
The Goddess of democracy? "The tyrants     Name:    Valentin Pepelea
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