🚀 go-pugleaf

Hello,
  Some time ago I complained to this list that I cannot format the 33 sectors
per track 3.5 inch diskettes (this is the distribution format) with the new
edition of diskette driver. By the old driver I mean rb37c65 Ed. 1 and by
the new - rb37c65 Ed. 4. Now this problem is solved and here are the results.
I could not get any help so I got these results in the hard way - by studying
the disassembly of the drivers.
  The old driver uses the OS9 ver. 2.3 convention to determine the diskette
size - by looking at bit 0 in PD_TYP field in the device descriptor. The
new driver uses the ver. 2.4 convention by looking at bits 4-1 in PD_TYP.
The old driver uses one of the three fixed values for Gap 3 in the track
format. The new driver uses a formula to determine the length of Gap 3. However,
this formula has a bug resulting in negative value of Gap 3 if the old conven-
tion for PD_TYP is used. This results in a very long track and the last
sectors overwrite the first sectors making the formatting impossible.
 Using the new style descriptor and the new driver I can now format the 3.5
inch diskettes with as many as 37 256-byte sectors per track. This gives
the capacity of 1.44 Mbyte per diskette.

  Regards,
 Andrzej Kotanski