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Re: "Universal Boot Initializer" ?



Replying to myself.

The best I can see the usage of DOS 3.2 with a 16-sector bootstrap would be to use 3.5 tracks, rather than 3, thus:

Track usage as seen from DOS 3.3 on the left, 3.2.1 on the right.
# - native sector. % - non-native "sector", shown stretched or squashed by 410/342. (this may be inaccurate)

 0123456789ABCDEF  0123456789ABC
0#####     %%%%%%  #####    %%%%
1%%%%%%%%%%%%%%%%  #############
2%%%%%%%%%%%%%%%%  #############
3%%%%%%%           ######

Basically, a few "common" sectors written on track 0 both in DOS 3.2 style and in DOS 3.3 style, then 2.5 tracks containing the rest of the DOS image, probably 3.2.1, reordered and with a different loader. It may even be possible to have track 0 reread AFTER the base rwts is loaded, and load up to 4 additional sectors there. Maybe others could be freed up and it would actually fit in 3 tracks, allowing for no loss of capacity.

Formatting would of course require a separate tool... there's no way in hell to ram all that code into DOS 3.2.1 space.

-uso.