6 Mar
2005
6 Mar
'05
3:35 p.m.
On Sun, 2005-03-06 at 13:59 -0600, Jim Battle wrote:
I think people have the wrong idea about this product.
There isn't
corporation behind these cards -- it is a labor of love by one
individual supported by a number of hobbyists. It is a real company
making them, just a tiny one. Yes, you will have to write your own
software if you are expecting to read/write disk formats that aren't
already supported.
Fair enough - but is any associated code produced by them (not
by
individuals using the board) open source? Are schematics and other
technical info published? It's a little worrying if it's a small group
of people doing it almost for the fun of it, but the product is a
closely guarded secret.
One pain about using the card was that I had to use it
on an Win98
machine so I could do simple I/O to the thing. XP doesn't allow it
without drivers. Apparently under linux is isn't so hard. Anyway, this
time around they are working on a driver with a mostly common API
between linux/XP/otherthings so that you don't have to mess with the low
level IO and just program the thing without jumping through hoops.
So hopefully source is published, API is available in advance on a
website somewhere, and the documentation exists to access the low level
I/O *if needed* ? That's something I'd expect of a product where so much
of the usability comes from the user themselves.
There are no hard real time constraints to programming
it, making it
very simple. On MK3 boads you manually step it to the track you care
about then you tell the controller to read or write a track. All the
transition information gets captured in a RAM. When it is done you read
out the data or write the next track to the RAM. MK4 adds more logic to
tell apart the index hole from sector holes plus a state machine and
some other control bits to allow reading/writing individual sectors on
hard sectored devices.
That (the MK3) sounds very like what's been discussed here in the past,
in terms of hooking a floppy drive up to something with enough RAM to
buffer a track, which can then be interpreted in software by a machine
at its leisure...
If you expect it to be plug & play for some
oddball format, you will be
disappointed. If you don't mind spending a week of evenings writing a
decoder/encoder in software, then it is a great card.
Absolutely. And it sounds like a decent bit of hardware. But I'm
concerned about what support may be available, how much sharing of code
goes on amongst users so that work isn't duplicated, what info is
available in advance to ensure that it'll do the job required - and also
which (broadly) formats it *still* won't be able to handle at the end of
the day.
I believe it'll handle reading / writing DEC media, and presumably
*anything* soft-sectored using FM / MFM. Anyone know about GCR type
formats? It'd be useful if we could just put together one machine with a
variety of drives on it and potentially handle backup / restore of just
about anything, but whether that's achievable is another matter.
Hmm, that's another point - how many drives can the board interface?
We'd likely need more than the four supported on a standard floppy bus -
but I've seen a photo of a catweasel with two floppy connectors, so
maybe it'll cope with 8 drives? At the very least the ability to switch
drives on a running machine and reinitialise the catweasel without a
reboot would be useful!
(Not asking you these things specifically - just anyone on the list who
may happen to know!)
thanks for the info :)
J.