Path: utzoo!mnetor!uunet!mcvax!unido!tub!tmpmbx!netmbx!hase
From: hase@netmbx.UUCP (Hartmut Semken)
Newsgroups: comp.sys.atari.st
Subject: Re: Writing to the cartridge port.
Message-ID: <1745@netmbx.UUCP>
Date: 17 Apr 88 18:05:06 GMT
References: <8804132155.AA23202@ucbvax.Berkeley.EDU>
Reply-To: hase@netmbx.UUCP (Hartmut Semken)
Organization: netmbx Public Access Unix, Berlin
Lines: 18

In article <8804132155.AA23202@ucbvax.Berkeley.EDU> 440488@UOTTAWA.BITNET (Doctor Who) writes:
>  How did Alpha get around this so that the Megadisk would work with
>out creating bus errors?

It's easy: whenever you *read* the adress range from FC0000+ you
actually *write* an adress to the adress bus, right?
Now: read adress FC000+(A1) with (a1).b containig the data to be
written. A simple PAL can write the Data into RAM.

Works just fine as an I/O Port. I attached an IBM-PC hard disk
controller (OMTI) to this I/O and use the interface for EC-BUS card as
well.

hase
-- 
Hartmut Semken, Lupsteiner Weg 67, 1000 Berlin 37 (auf der Karte: links)
hase@netmbx.UUCP
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