A-500 and HD floppy Q's
16 messages in this thread
All the Commodore releases are saying that the newer high-density
(1.44-Meg) drives cannot be used with the A-500.
Question: Is this a flaw in the hardware itself, or just that the new
drives are not laid out to fit into the 500's case? (i.e. if I rebuilt my
500 into a desktop or tower case, would the HD drives actually WORK with
it?)
When I do (eventually) go ahead and re-case my computer, it might be
nice (since my 500's original disk drive is 7 years old, and due for a
refit) to put a 1.44 Meg drive in there instead of a 720K one.
What I what to know is who is the idiot that put a 880K drive in the
A1200….who needs an HD floppy more: an A4000 user who has to get a
Harddrive with his system or an A1200 user who might decide to become a
'floppy swapper' due to financial reasons??
This also adds to the degree of incompatiblity between the two machine.
As usual, good machines, bad marketers……
Dave
Elite MicroComputers – via Whap!
Dave:
Not to mention that if the A1200 had come with an HD floppy, it would have
given a green light to developers of 3.0 only utilities to distribute
their work on HD floppies.
// -Mike Schiller
\X/ AMIGA! On AutoPilot in sunny Fort Lauderdale
Good point…..
Elite MicroComputers – via Whap!
Mike,
It is my understanding that Commodore wanted to use the new high density
drive in the A1200. However supplies were short and they did not want to
hold the machine up because of this.
I understand there will be HD upgrade kits made available sometime in the
future.
-mark=
If supplies where short why did so many leak out in A3000's ?
Dave
Elite MicroComputers – via Whap!
Well, I can answer that one. It seems that there was a mistake made with
the A3000s. Commodore told me that it was some clown in the warehouse who
picked the high-density stack instead of the low-density stack of drives
when he was picking up boxes of drives for integration into the machines.
Ergo–Some A3000s got high density drives.
At least that is my story. 🙂
-mark=
Sounds like a crock to me…..most likely it was C='s way of beta testing
the drive.
With the last statment you made…they were not in stock….I noticed
something. The A1200's floppy is an A1200 floppy….it's not the normal
880K drive…it looks alittle more cut down for the slim 1200 case.
So the question now is….why did they bother making 880K drives instead of
1.76's ? Basicly they redisigned old technology for their new standard
computer.
Dave
Elite MicroComputers – via Whap!
I read this in one of the Toronto show reports…. but it seems that the
form factor of the custom HD floppy is too large to fit in the 1200's
case. It uses the shorter drives, like the Air Drive internal for the
2000. Apparently, there aren't any custom HD floppies in that size *yet*.
Jim
That is a bull$@^@ excuse for not have a HD drive…..I'm not sure how C=
does it….but from a techs point for view all that need be done is halving
the voltage to the motor when the HD button is released. This can be done
with resistors. Or simply using a dual speed motor.
I'm not sure how C= went about doing it….but it can't possibly be that
complicated.
Dave
Elite MicroComputers – via Whap!
There's more to it than that. The halving of the drive speed has to be
done by regulated circuitry; you can't just stick resistors in there…
even more, uh, interesting, is that any magnetic read head's ability to
sense fields is highly dependant on the wavelength of the field, and a lot
of techno-garble factors like the permiability of the read head and etc.
When you change the platter speed, *everything* changes – the strength of
the applied field, wavelengths, etc.
That's why you can't just hack a std drive to read high-density media.
Also – and I know this for a fact – the Amiga's ability to read and writes
disks is pretty darned poor. I have no idea why, but as far as floppy
performance, over the years I've used Amiga's, I've grown to distrust its
floppy systems to the point of paranoia. I'd really rather they at least
used the right dirves, anyway.
–Ben
…via AutoPilot
Ben,
I thought one of the reasons that the Amiga floppy drive is so poor is due
to the fact that Paula has been given the job of decoding mfm.
-mark=
That could well be. Whatever the reason, I try VERY hard not to use them.
–Ben
…via AutoPilot
Yeah, well, I wasn't too thrilled by that explanation either. Especially
since the HD floppies are supposed to be on the way. At least it's a
possible source of revenue for us dealers. 🙂
Like Ben says, you can't drop the speed of a motor with a resistor. Well,
you *can* but it's poor practice. I spent some time thinking about hacking
a standard drive. My notion was to either divide the tach signal from the
motor by 2, or use a cmos switch to cut in a different resistor for the
speed adjustment pot. Halving the motor speed would drop the signal level
from the read heads too. Might have to change the gain of the read amps as
well. But that's just a guess. By then, it would be easier to hack a set
of chips from a clone controller onto a autoconfig card and use a standard
drive. …
Jim
Dave, you can't just cut the voltage in half to the motor to run half
speed. Depending on how the field is set up in the motor, the motor will
either run les than hald speed, or have next to nothing for torque.
It is more complicated than that.
73, Kelly
ok sorry to all…..I don't really work with robotics (servos, motors) and
was just using 8th grade general science. Which in BASIC THEORY could
work…..but a dual speed motor would handle it.
Dave
Elite MicroComputers – via Whap!