Re: SpeedDOS

From: Ingo Korb <>
Date: Sat, 07 Feb 2015 01:22:50 +0100
Message-ID: <> writes:

> Some instructions even accessed the memory at $1800 and $1C00. That
> would make sense if I was dealing with a 1541, but not in a
> C64. Unless it is code that is meant to be sent to a 1541. But why,
> having its own SpeedDos ROM as well?  I compared this ROM to other
> ones I had. Although different, they had these weird instructions as
> well. What to make of that?

SpeedDOS does indeed send code from the C64 to the 1541 for loading (and
probably saving) when it detects a parallel handshake. That code
even jumps directly to modified parts of the SpeedDOS-1541-ROM, so
mixing different C64/1541 SpeedDOS-ROMs can result in combinations where
LOAD crashes the drive.


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Received on 2015-02-07 01:00:04

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