Connecting a 5¼" floppy disc drive via USB?

[Dave Moll]

I use a USB 3½" floppy disc drive to transfer data between my main computer and the older computers in my collection, but some of them only have 5¼" floppy drives, thus necessitating a two-stage process of copying data to 3½" disc and copying it again on a computer with both size drives.

I've been having a rather silly thought... what I would really like to do is to modify a USB drive, replacing the 3½" drive with a 5¼" one. If I could obtain a unit that used a standard drive connected to the interface, it would presumably simply a matter of disconnecting the included drive and connecting cables to a separate 5¼" drive. The problem is that both the drives I have have a floppy unit made specifically for the purpose, and I assume this is generally the case.

Does anyone make a USB floppy drive interface that uses a drive with the standard connections as used for an internal drive?

I expect this idea is a total non-starter, but I thought I'd just ask.

[mark pirate]

I think it could be possible, I have a couple of stand alone 3.5" drives that connect via usb, I am sure that they are just standard drives, so it should be possible to connect the interface to a 5.25 drive if you can match the pinouts.

Mark

[Dave Moll]

Matching the pinouts shouldn't be a problem. I'll see whether I can find USB drives that contain unmistakably standard drives.

[paulsherwin]

Why not put everything on the net? Even 8088 PCs running DOS can do this. I've got several old ISA network cards somewhere, and I'm sure other members will have lots they don't want. On a DOS machine you just need a packet driver for the card and MS-Kermit.

[cmjones01]

If you want to get serious about floppy access via USB, there's always Kryoflux:

http://www.kryoflux.com/

which is intended for recovery and archival of more or less any floppy format ever invented. It supports at least 3", 3.5", 5.25" and 8" drives with the appropriate wiring.

Chris

[Dave Moll]

Chris,

That looks very interesting, especially if it supports 3" and 8" discs. Though I find it worrying that they stay well clear of mentioning any prices other than free software included. I tend to apply the same maxim here as I do with stalls at fairs - "no price, no sale". If I have to express interest first, I lose interest. In this case, I suspect that we're talking about serious money.

[cmjones01]

They do mention the prices in the online store (there's a link to it at the top of the page). It's about 100 euro for the board, which I think is not bad at all.

(no connection, just glad people are making these things!)

Chris

[Freya]

Checkout their floppy drive prices, ouch. or maybe just out of stock

[mike_newcomb]

Hi Dave,

perhaps an easier way, is consider using a dual/combination drive.

These only have one interface but cater for both sizes of floppy disk.

Google:- 'teac fd505'

There is a pdf document there full of information.

Good Luck - Mike

[Dave Moll]

Chris: thanks, I'd missed the link at the top. €95-€115 doesn't sound too bad - especially (as Stephen notes) compared to the ludricous prices for disc drives. Fortunately, I've nearly a cupboard full of spare drives - including 3½", 5¼" and 8". No spare 3", except that I do have a couple of PCWs not in working order that might act as organ donors!

Perhaps I should have a go at selling some of my old drives at nearly €1000 a time! hahaha

[Dave Moll]

Mike: I'm not actually looking for drives (see above post). In fact, I think I've got one of those dual drives somewhere. The Kryoflux gadget certainly seems to do what I'm looking for, but if it is cheaper to get hold of a second-hand USB drive unit containing a stand-alone drive that I can substitute with an external 5¼" drive, then so much the better. Really at the moment I'm just trying to establish for sure whether such USB devices exist before I start trying to find one.

[paulsherwin]

I'm pretty sure the cable interface for both sizes of drive is the same - the 5.25" drives use an edge connector rather than a ribbon cable socket, but there are lots of adapters around (I think I've got one in the junk box). This should mean that you just need to unplug the 3.5" drive from the USB adapter and plug in the 5.25 one.

[Dave Moll]

Sorry, I should have said that I have cables. What I'm trying to track down is a suitable USB interface - or whether ones with standard drives even exist.

[mhennessy]

Just a thought - I'm pretty sure that 5.25" drives require +12V in addition to +5V. An external USB adaptor will rely on the fact that 3" drives just use +5V.

Of course, the easiest way to get around that is to power the drive from a spare connector in the PC.

[Dave Moll]

Ah, a good point. Yes, I believe that is the case, so I'll need a separate power feed - not an insurmountable problem, though.

I notice that the top-end Kryoflux includes a power supply - presumably for just this reason. I think it may be the best solution to stick the hundred quid or so for one of these into my budget in the near future, especially if it gives me the possibility of adding 8" and 3" options in the future.