Creating an 8-inch floppy from 3.5-inch Teledisk image

Dave Dunfield dave06a at
Sat Mar 24 16:36:20 CDT 2007

Btw, if anyone still needs them, I have converted the ACS8000 disks
in question to .IMD format and posted them to my site.

The CP/M 2.21 and 2.24 disks are both single-density all the way
through and converted with no problems.

The CP/M 2.24A disk appears to be a double-density disk with single-
density boot tracks - There were two problems:

- Tracks 70-77 are missing sector 6 for some unknown reason...
  However I checked with IMDV and the other sectors on these
  tracks do not contain data - so it's not likely to be a
  problem as a boot disk.

- Track 2 appears as a single 128 byte SD sector with sector
  ID #100 - don't ask me why ... ImageDisk read it OK and
  stored it as read. TeleDisk gets the same thing (single
  128byte SD sector with id=100), but after that it gets
  confused and thinks the disk is a 48tpi disk in a 96tpi
  drive and double-steps the the rest of the disk, complaining
  all the way that the cylinder IDs are wrong) ---  so I
  can't say if this image will actually work or not.


dave06a (at)    Dave Dunfield
dunfield (dot)  Firmware development services & tools:
com             Collector of vintage computing equipment:

More information about the cctech mailing list