1 Oct
1998
1 Oct
'98
5:10 p.m.
On Thu, 1 Oct 1998, Allison J Parent wrote:
Apple used GCR coding for their drives and there are
no commonly
available chips that do. In fact the apple does not use the traditional
floppy disk controller chips at all. The FDC logic on the Apple is
rather simple and the CPU provides the brains as a software FDC.
It was part of the idea of using software to replace hardware to make
the machine simpler and less expensive.
And more hackable. Imagine being able to create your own disk formats!
Clever developers did this. Probably the most interesting was the
18-sector DOS that Broderbund used on some of its later Apple ][ games.
This served two purposes: 1) it allowed more storage space for programs on
a single disk (normal Apple DOS only had 16 sectors) and 2) it foiled
software pirates as you now had to figure out ways to cram 630 sectors
worth of data onto a 560 sector normally formatted disk so it could be
copied with a regular disk copy program (I solved the problem for myself
my writing an 18-sector disk copier using the RWTS [DOS] of the game).
Sam Alternate e-mail: dastar(a)siconic.com
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