PDA

View Full Version : Amigas and HD floppies



AndyLandy
20th September 2009, 07:37
What's the difference between a PC and an Amiga floppy drive? I was always led to believe that the actual drives were the same, and it's the controller that limits PCs to constant angular velocity formats. Of course, you'd need an Amiga with a controller that knows about HD disks, but many of the big-box ones already do. So, the question is thus: "Can I bung in a PC HD floppy drive and expect it to work?" and "If not, why not?"

:thanks:

JLPedro
20th September 2009, 10:26
From my experience (and by no means i'm an expert on the matter) most PC High density drives can be modified to work as a 880k DD amiga drive, as long you can make some modifications to the wiring (ready signal for example). As for an PC HD floppy to work as a Amiga HD Floppy thats another story as amiga HD floppy spins at half the speed of an PC HD floppy, so it can only be done with the help of extra hardware. I normaly look for Samsung 321b HD floppy drives and convert them to 880k Amiga DD Floppy, as they are still sold new and are very easy to hack, giving 1/1 compatibility to amiga standard DD drives.

Some links on the subject:

http://www.freewebs.com/computolio/amiga_floppy_compatibility.html
http://www.rabayjr.com/amiga_floppy_drives.htm

Hope it helps.

RedDaemonFox
20th September 2009, 14:56
get a catweasel and be done with it, it allows ALL formats, HD and DD

Justin
20th September 2009, 15:09
get a catweasel and be done with it, it allows ALL formats, HD and DD

except it's really unstable and the drivers are poo

JLPedro
20th September 2009, 15:25
And you can't boot from a catweasel drive....

Harrison
21st September 2009, 17:11
get a catweasel and be done with it, it allows ALL formats, HD and DD

except it's really unstable and the drivers are poo

Is that only in regard to the Amiga based Catweasel controllers?

I've been using a PC PCI CatWeasel MK4 recently and it has been really good, stable, and read and wrote everything I've tried.

AndyLandy
21st September 2009, 21:46
My query specifically relates to using high-density floppy disks on an Amiga, either 1760k FFS-formatted, or 1440k FAT12-formatted ones (via CrossDOS)

Mostly I ask because I have a stack of crummy old PC floppy disk drives, and wondered whether I could just drop one into an Amiga and have it work. I don't need the functionality so badly that I'd pay for Catweasel, but if I could achieve it with existing hardware, it might be worth a go. It looks like a Chinon FZ-357A is probably my best bet.

rkauer
21st September 2009, 23:35
Do you need a converted unit to use in which Amiga?

I discovered that any pc floppy can be converted to Amiga using a small hack. Problem can arise for wedge Amigas, which needs the eject button in the far right position or you need to create a new button or (bad) enlarge the original hole with a scalpel.

Soon on the Amioracle section. :wink:

AndyLandy
21st September 2009, 23:48
At the moment, I'm mostly interested from a theoretical point-of-view, all my Amigas currently have working DD drives. I was mostly interested in whether it's easy (cheap) to upgrade to HD.

That said, some technique for making a PC drive work in an Amiga (even if only DD mode) would be very useful, since the original drives will be very old by now. I expect a drive will fail on me sooner-or-later.

rkauer
22nd September 2009, 03:17
The hack itself is easy to do: just invert pins 2 x 34 and join pin 30 with the "new" #34. Also modify the drive to DS0: for proper operation.

I'll add a picture if needed.

asm1
11th October 2009, 14:56
At the moment, I'm mostly interested from a theoretical point-of-view, all my Amigas currently have working DD drives. I was mostly interested in whether it's easy (cheap) to upgrade to HD.



If you can find one.... Power Computing made both Internal and External 1.76MB drives for the Amiga. I managed to get hold of an External XL unit.... whilst not "PC Floppy drive cheap" it was less than half the Price of a Catweasel card for my Amiga. They seem to crop up every now and then on ebay. I got mine boxed with manual and drivers disk :blink:

And jolly nice it is too. :thumbsup2:

Andrew

Harrison
12th October 2009, 16:00
I've got one of those Power Computing XL drives and they are great. I bought mine back when they first came out and paid something mad like 140 for it. For a floppy drive! :o But at the time it was the only way I could use HD floppies with my A1200 to access 1.4MB PC and Mac floppies on the Amiga to access files between my Amiga and university.

Now the Power Computing XL drives do come in two models/versions, so if you look for one take this into account. The first of the XL drives came in a very similar plastic case to their standard cyclone (X-copy) compatible 880B Amiga drives and look identical except for an extra switch on the back for the high density selection. The later XL drives came in a nicer looking, slimmer but slightly longer, and more robust metal case. Neither of the drives actually has any writing on it though to say it is an XL HD drive, which is annoying, and means that sometimes you can find one by accident as sellers don't always realise.

rkauer
12th October 2009, 16:52
My Power XL had the PGA chip fried some few years ago... :cry: