Trying to Create LDOS Model III Diskette
#1
I use HxC to convert DSK images to SCP files. When I load an LDOS 5.31 for TRS-80 Model III into HxC, HxC correctly shows it as a 40 track single sided disk. When I convert it to an SCP file and load it into SuperCard Pro, it shows as a 20 track, double-sided disk. If I write it to a real floppy, it won't boot on a Model III. Is there a better way to convert DSK files to SCP? There are many cases where HxC doesn't create the output SCP expects.

Tom L
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#2
In SCP's Copier load the image file, click on the OVERRIDE box, and then change the disk type to be C64.  That will write a single sided disk.

I have also seen cases where HxC converts a single sided disk into a double-sided disk.
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#3
(05-02-2020, 03:50 PM)admin Wrote: In SCP's Copier load the image file, click on the OVERRIDE box, and then change the disk type to be C64.  That will write a single sided disk.

I have also seen cases where HxC converts a single sided disk into a double-sided disk.
Whenever I change the disk type, the loaded image disappears and the Make Disk button is grayed out.
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#4
The problem is that there are 4 different formats for 5.25" disks - siingle sided 40 tracks, single sided 80 tracks, double sided 40 tracks, and double sided 80 tracks.  I have settings for TRS-80 and IBM360K, which are the same.  SCP is expecting these image files to be double-siided 40 tracks.  I may end up having to add new disk types to handle this.  Right now, it seems that HxC is setting the disk type to Atari ST, which completely wrong!

The override does kill the image in memory, so that won't work.  I just found the LDS5.3.1 image file and converted it with HxC and it definitely creates a SCP image as a 20 track Atari ST formatted disk image.  I need to forward this to Jeff for him to look at.
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#5
(05-02-2020, 04:10 PM)admin Wrote: The problem is that there are 4 different formats for 5.25" disks - siingle sided 40 tracks, single sided 80 tracks, double sided 40 tracks, and double sided 80 tracks.  I have settings for TRS-80 and IBM360K, which are the same.  SCP is expecting these image files to be double-siided 40 tracks.  I may end up having to add new disk types to handle this.  Right now, it seems that HxC is setting the disk type to Atari ST, which completely wrong!

The override does kill the image in memory, so that won't work.  I just found the LDS5.3.1 image file and converted it with HxC and it definitely creates a SCP image as a 20 track Atari ST formatted disk image.  I need to forward this to Jeff for him to look at.

Is there a solution to this? Facing the same problem now.
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#6
Looking at the .SCP that the HxC software produces it is clear they are setting the ID byte incorrectly. Byte 04 was set to 14 and it should be 40. I used HXD hex editor to fix this and the .SCP file now comes up as TRS-80. There is still another issue though, Byte 08, Bit 0 is set to 1 to indicate the index should be used but the SCP software seems to ignore this. There may be some other config bit that I have overlooked though.

With Byte 04 fixed it is easy to set it to use the index and this will not erase the loaded file.

   
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#7
I found that if Byte 5. #Revs, was set to anything other than 1 the Index bit is ignored. Setting Byte 5 to 1 will now bring up the file in Index mode. It is odd that it only shows 19 tracks although the file clearly says $27 (decimal 39). It seems to write across the whole disks surface though, so we'll see if the disk works or not.
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#8
I can't find any way to make the SCP actually write a single sided TRS-80 file correctly. No matter how you have the ID byte configured it will change things on its own. You can set it to TRS-80 1SDD and it will come up with Atari or Amiga. It is not even consistent except that is shows as only 20 tracks.  If I load the same .SCP in HxC it correctly identifies it as a 1S 40 track file. It only writes 20 tracks, frustrating...
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#9
If you dump the disk with SuperCard Pro it creates the proper image. All TRS-80 disks are dumped as two sided with the SuperCard Pro software - no exceptions (even if you had a real singled sided disk). So, anything that takes a .scp image for a TRS-80 disk and shows it as a single sided disk would be decoding the data incorrectly.

I will have to look at some way to add a single sided mode for TRS-80, but I wont have a way to test it because I only have double-sided everything.
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