I just want to do a catdir and catcopy of the disks I have and copy the
contents to my local PC hard disk. I have a bunch of C64(5.25) ,
Amiga 800's(3.5) and Apple ][ disks (5.25)
Occassionally it'll read a C64 disk, no luck with the others.
Curt
Jim Battle wrote:
Fred Cisin wrote:
Multiple choice:
"It can read xxxx disks" means:
...
B. It can read the physical disk, and has software that will
permit making an exact duplicate of the disk and/or creating
a file that contains an image used for replicating the disk.
...
The Cat Weasel appears to be able to do A, C, and
maybe B.
Actually, I'm mucking with a catweasel card right now.
I took Tim Mann's code as a starting point and I'm going from there.
I don't have any use for his decoding routines nor of making virtual
disk images since my needs are different. However, I can't imagine
how many hours of work he saved me by having routines that locate the
card in PCI space. Also, his "trackhist" program provided some very
useful subroutines. With the help of Tim's code, it took me less time
to modify/write the code to decode the disk format than it did to rig
up the 34-pin to 50-pin ribbon cable adapter.
Anyway, I can provide an example disk format where the catweasel, as
it stands, can't write the disk image, at least not without some
dodgey trial & error (try to write a track, read it back and if it is
mucked up, try and adjust the write timing for the next attempt. Even
then, there is a lot of luck involved).
Hard sectored disks are a problem for the catweasel to write. There
is a function to write from index mark to index mark, except the
catweasel assumes there is just a single index mark per revolution.
Thus, you can write one sector, but you can't even reliably tell it
which sector you want -- it just starts at the next index hole that
appears. Perhaps under DOS you can disable interrupts and figure out
via polling when sector N is about to appear and use index-to-index
write mode. Even this doesn't suffice for the disk format used by the
Processor Tech Helios system. It ignored every other sector mark so
that effectively there were 16 256B sectors instead of 32 128B
sectors. Further, blocks of data could be larger than 256B -- they
simply spanned more than one sector. Thus, this mode is useless for
that scheme.
You can do a write where you specify "wait for an index hole, then
write this sequence of transitions". The problem is that due to speed
variations you can't say that index 5 is going to come exactly (166
2/3 ms / 32) after index 4. That is where you could try to write the
whole track, then read everything back to see if you succeeded and if
not, adjust the clock pulses wider or shorter to make things line up.
Oh yeah, in this mode I think it doesn't wait for an index hole, it
just goes whenever you tell it to, so good luck trying to get the data
to line up with the index marks at all.
As it turns out, now that I have the catweasel set up and running,
there are three disk formats that I would personally find useful to be
able to decode -- 8" Helios, 8" Wang 2200, and 5.25" Northstar. Guess
what -- all three are hard sectored formats. Luckily, I'm really only
looking to use it to archive virtual disk images, not to create new
disks.
--
Curt Vendel & Karl Morris
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