1541IDE: weird problem

1541IDE: weird problem

From: Ruud_at_baltissen.org
Date: Sun, 17 May 2009 08:45:36 +0200
Message-ID: <4A0FCEB0.32088.41159F@Ruud.Baltissen.org>
Hallo allemaal,

Testing the version with harddisk and floppy I encountered a weird problem. 
I tried to load '64 DOCTOR V1.1', a test program written in Basic, 83 
blocks big. But it only took a fraction of a second to load. Suspicious I 
listed it and only got a line with rubish.
Trying to load one of the files on the second page of the directory I got 
as listing: '8244 DOCTOR V1,1'. 8244 in hex is 2034 or '<space>4' -> '4 '. 
Thinking of a read or write error I scratched the file, loaded '64 Doctor' 
from the original disk and saved it as '64DOCTOR'. Now the listings showed 
'17460 OCTORCLOSECLOSECLOSE <etc.>'. FYI: CLOSE = 160, shifted space. And 
64DOCTOR wasn't loadable as well. 
Regarding the listings: IMHO a program lists the name of the first program 
of the next directory sector. 

A disk editor showed nothing wrong with the file itself. After copying the 
data from the harddisk to another floppy, loading a file from this floppy 
was no problem. So the problem lays in how the harddisk part of 1541IDE 
handles the data, not in the data on the disk.

Next I created a new partition and started to save the well known 'UNI-
COPY' from Commodore as 'F1', 'F2', 'F3' etc. etc. The moment I saved F17, 
F9..F16 became unloadable. F17 was still loadable. Saving more files, 
F17..F23 became unloadable the moment I saved F24. Weird exception of the 
rule: F1..F8 remained loadable all the time.  
Deleting all the files from F10 on didn't change things: F9 still wasn't 

A long shot, but you never know: Does anybody know where I could have gone 

This all means I have to start debugging the loading proces. But to be 
honest, I have no idea how a file is loaded. Until now I didn't have to; I 
only had to intercept the proces the moment the hardware was involved. I 
think I know where to start but any info in the form of which subroutines 
are run and in which order are welcome; it could save me some time. TIA!

   / __|__
  / /  |_/     Groetjes, Ruud Baltissen
  \ \__|_\
   \___|       http://Ruud.C64.org

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Received on 2009-05-17 08:54:20

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