Re: Disk II 70 Tracks

[Rubywand <rubywand@swbell.net>]

Bryan Parkoff writes ...
> 
>     Previous post states that odd tracks are not used.
> Do you know what odd
> tracks contain garbage data?  Someone said that we
> may be able to modify DOS
> 3.3 to handle 280KB instead of 140KB.  Is it true
> that Disk II Family has an
> ability to read/write both odd-even tracks in full
> that it may be capable to
> handle 280KB.  Is it possible that even tracks might overwrite odd tracks
> that will not be supported?  Please advise?
> 
 ....

     The chief limitations on available disk space are the particular drive and
diskette capacity. On the usual 5.25" DD diskette side, you can get an extra
track on practically any Disk II drive without any hassle. (Adding the extra
track-- 36-track DOS-- was a popular mod for a while.)

     The mod plus the fact that some games, etc. came on 36-track disks (mostly
for copy protection) led to having Disk Muncher automatically try to copy 36
tracks. The version of Copy II Plus on the TNILUTIL.DSK (on Ground) is set up
to try most operations with the assumption that the diskette may use 36 tracks
(which, naturally, gives an error for Track 35 if it doesn't; but, it's still a
useful feature).

     Usually, there isn't anything between tracks except space to make sure
that writing on one track doesn't corrupt data on an adjacent track.


     Some newer A2 5.25" drives, usually half-height models, will go up to 40
tracks per side. There are 40-track versions of DOS 3.3 around-- e.g. a fast
40-track EsDOS.

     Beagle's Protodos (fast DOS 3.3, the basis for EsDOS) removed some of the
pressure for using the extra-track DOS 3.3's because it frees most of Track 2
(wasted by regular DOS 3.3).

     Once Apple II users moved to 3.5" diskettes, the attraction of extra-track
DOS 3.3's declined rapidly. It turns out that the advantages of sticking with
the standard 35-tracks-- being sure other users can access your atuff and being
able to use all those utils that expect just 35 tracks-- almost always outweigh
the benefits of having extra tracks.


Rubywand