8 Oct
2007
8 Oct
'07
1:46 a.m.
On 7 Oct 2007 at 19:28, Tim Shoppa wrote:
Now, IBM 3740 floppy format (from which almost all
modern floppy
formats have descended) has a lot of 8-bitness in it. But it
was still used by 12-bit machines (with various packing/repacking).
There's a whole lot of crap in the IBM 3740 floppy format that
nobody has used for decades but is still carried around, too. (e.g.
"deleted data" marks).
...and if you check some IBM 3741 floppies, you'll find that only the
first 80 characters of each 128 character sector was used on most
systems (128 characters was a maximum and many installations elected
to retain their 80-column card format).
Since the 3741-created diskettes held roughly a box of cards, how
else would you delete a card, except to use a "deleted data mark"?
Cheers,
Chuck