On Thu, 2005-03-10 at 17:18 -0800, Steven Canning wrote:
Jules,
I proposed doing exactly that (i.e. passing "raw" floppy data through a
parallel port) last year along with some simple math that showed it could be
done.
Yep, I hadn't forgotten :-) (I made sure I kept all the relevant
messages too)
Wasn't the problem that the parallel port just doesn't have the raw
speed for it to work for all disks though? At which point buffering
becomes necessary, which was also the point that everyone went quiet on
the subject :-)
With the cable you mention, how are you supposed to get the created disk
image back onto a disk again? (Personally I need to be able to restore
data from an image back to a floppy)
I need to do some reading up on what the floppy drive's write gate
signal does. If spitting data from an image down the 'write' signal wire
at the same speed as it was read is good enough (and 'write gate' is
actually a 'R/-W' signal) then maybe it isn't too complex. However if
write gate is actually dependant on the data stream too (needing it to
be understood) then it could be rather tricky.
Note that personally I *don't* need to understand the image on the host
machine (at this stage) - all I care about is backing up floppies to
modern hard disk and being able to recreate them again. Understanding
via software decoding might be nice one day, but in the shorter term my
concern's with all the thousands of disks we have at the museum with
data on that are likely decaying...
cheers
Jules