Re: C64 IEEE interface

From: Michał Pleban <>
Date: Sun, 09 Nov 2014 10:54:22 +0100
Message-ID: <>
Hello! wrote:

> I have read it and my first impression is that you do something 
> wrong. To make sur I have to read it again. 
> The protocol of detecting the present of any drive is simple: make 
> ATN (L) and NDAC and NRFD should become (L) as well. If they don't, 
> no IEEE device is present.

That's what I thought when I started to develop the cartridge, and
that's how I originally coded it. Which did not work at all at some cases.

Please do an experiment yourself. Fire up a Commodore 610, do not
connect any drive to it, and try to open a file on disk #9 - see when
error messages you get and when.

Then connect a drive #8, and again try t open a file on disk #9 - see
the difference.


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Received on 2014-11-09 10:00:02

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