looking for a 'modern' 5.25" floppy drive

[sqpat]

looking for a 5.25" floppy drive i can stick into a newer computer so that i can create a bootdisk or whatever I might need. (These connect just like 3.5" floppy drives right?)

 

[Jorg]

looking for a 5.25" floppy drive i can stick into a newer computer so that i can create a bootdisk or whatever I might need. (These connect just like 3.5" floppy drives right?)

Yes they connect like 3,5" ones, but:

- The BIOS of most recent PC's do not support 5.25" floppy drives anymore

- To make 360K boot floppies, you might need a 360K 5.25" drive. 360K floppies written by HD 1.2 MB 5.25" drives might not be readable in a 360K drive on the vintage machine

- Windows XP and newer does not support 360K 5.25" drives

 

[sqpat]

I see. Well it probably wouldn't be terribly hard to stick an installation of freeDOS or some version of linux on a newer computer and they'd have the drivers to communicate with the floppy device right? That should take of the BIOS/WinXP issues. As for the 360K issues... you said "might!" Possibly by creating a full floppy image you can control where the files get written, or something. That's my guess.

 

[Ole Juul]

This discussion could get really complicated if we don't find out what sqpat means by "newer" computer. (Please tell us.)

Personally, I would set up what I call a newer computer, such as a 486 or P60-166 just for the purpose of keeping 16 bit software and hardware. That generation of hardware is still readily available anywhere in the world for free and has the proper BIOS support. Brand spankin new, cutting edge etc. really really new stuff (like P2-4) is just making it difficult for no economic or practical reason.

@sqpat: Don't forget that the 360 and 1.2 have different track widths which do not relate to software. It's worth reading up on.

 

[sqpat]

a "newer" computer is a 32-bit machine potentially running just about anything that would make this task easier.

While a 486 might be cheap to get a hold of, I'd have no room for it. If I could grab a 5.25" floppy drive that I could stick in one of my current desktops, that would be a lot more space efficient and convenient, even if I have to do some work to get it working properly.

As for DD/HD, as long as I have the 360k diskette, i can write to it with a drive that supports the DS/HD 1.2s right?

 

[Jorg]

As for DD/HD, as long as I have the 360k diskette, i can write to it with a drive that supports the DS/HD 1.2s right?

Write to it, yes. But that does not mean the disk will be readable in a 360K drive.

There is another thread going on about this which already proceeded a bit further:
http://www.vintage-computer.com/vcforum/showthread.php?t=15889

 

[Raven]

Yes they connect like 3,5" ones, but:

- The BIOS of most recent PC's do not support 5.25" floppy drives anymore

No... most that support 3.5" will support 5.25" as well still. The support isn't routinely tested, as most people don't use it, so it may or may not work well, however.

- To make 360K boot floppies, you might need a 360K 5.25" drive. 360K floppies written by HD 1.2 MB 5.25" drives might not be readable in a 360K drive on the vintage machine

Completely true. If you write files to a 360K floppy in a newer drive, or even in a 360K drive on a newer machine, it has a good chance of rendering the disk unreadable in older machines. If you format the disk to 360K (using special switches on the CLI format command), it will DEFINITELY be unreadable.

- Windows XP and newer does not support 360K 5.25" drives

While it doesn't distinguish between 360K and 1.2MB, just seeing it as a "5.25 Floppy", it does work, and can write to 360K disks fine. The issue, however, is that the newer hardware borks the disks by using slightly different timings (I'm not sure where or how these come into play). This means that while the disk will continue to be readable on the comp you write it on, and possibly ones with 1.2MB drives, it will not be readable with a vintage 360K comp. I know this firsthand, as I ruined many a 360K boot disk... :/ This could be because XP assumes that it's a 1.2MB floppy.

I think that either the age of the floppy controller or the speed of the system comes heavily into play when writing to a 360K floppy. I have dealt with them successfully on a Pentium MMX 233mhz in a proper 360K drive, so anything late Pentium and older should work fine. I don't know about P2/P3 (or AMD equiv), but I'd wager that you've got a 50/50 shot of it working with a P2/K6 era machine, though I'd try for a 300mhz if possible, in case it's clock-speed-based.

One final note: You don't need a "modern" floppy drive to connect to a modern computer. You can take an old floppy cable and use it in a modern comp, using the edge connectors to connect a 5.25" floppy. If you have one with only edge connectors you can use a small adapter (if you have them) to connect a 3.5" to a edge connector, but the preferred solution here is to get one of those 5-connector cables with dual 3.5" connector and dual edge connectors. Note that you may only use one connector in each of the two groupings (there is one 3.5" and one 5.25" connector in each "group", you may choose one for each of the two groups).

I hope this helps.. I've learned a lot about floppies, in similar situations to what you've got going, as I am a big fan of them. I ended up setting up a win98 PC (the aforementioned P233MMX) as a media PC, with a 3.5" 1440KB and a 360K for media transfer.

GL.

 

[Chuck(G)]

The DD 5.25" issue on a 1.2M 5.25" drive has nothing to to with timing. The heart of the PC disk controller is still the NEC uPD765, however buried under silicon it becomes. Timings for double-density media have remained the same since the original IBM 5150 (and before).

The issue at the heart of the matter is the track width. A "360K" drive puts down 48 tracks to the inch; a "1.2M" drive, 96. The way a 1.2M drive handles 360K media is to read or write every other track (0,2,4,6, etc.). This creates a problem when a 360K drive has to read the disk.

If there was any data written by real 360K drive on the disk or the disk was written in "720K" mode on the 1.2M drive, the 360K drive will pick up extraneous garbage from the odd-numbered tracks.

The way out of this if you have no 360K drive is to degauss disks before you format and write them in a 1.2M drive.

I use a VHS videotape eraser (audio degaussers generally aren't strong enough) to do this and the disks work fine.

 

[Raven]

The DD 5.25" issue on a 1.2M 5.25" drive has nothing to to with timing. The heart of the PC disk controller is still the NEC uPD765, however buried under silicon it becomes. Timings for double-density media have remained the same since the original IBM 5150 (and before).

The issue at the heart of the matter is the track width. A "360K" drive puts down 48 tracks to the inch; a "1.2M" drive, 96. The way a 1.2M drive handles 360K media is to read or write every other track (0,2,4,6, etc.). This creates a problem when a 360K drive has to read the disk.

Aye, I was guessing about the causes based on my experience, I knew another variable was track width, though, but I just woke up, so I didn't think to list that off. *feels nubby*

 

[mk553]

Don't know if this would work for you, but you might do what I did for my IBM XT, and just buy an 8-bit floppy controller that can support 1.2mb and 1.44mb floppy drives. (I can't remember if the XT would handle the 1.2mb on its own, but it definitely needed an upgrade for the 1.44mb).

So, with a legacy 1.44mb floppy also on my new screaming game machine, I have some way of transferring files. (I also networked them too, but that's a subject for another thread).

Good luck,

Mike

 

[sqpat]

ive got a multifunction card which supports floppy drives, and a couple floppy drives laying around as well. But my BIOS won't recognize the drive, it seems. Not on startup, anyway. I see the power light go on but that's it.

 

[Great Hierophant]

The way out of this if you have no 360K drive is to degauss disks before you format and write them in a 1.2M drive.

I use a VHS videotape eraser (audio degaussers generally aren't strong enough) to do this and the disks work fine.

Aren't degaussers a bit on the expensive side? The VHS tape and the floppy have very different physical characteristics, do you just put a floppy in where the VHS tape is supposed to go and hit "degauss"?

 

[Ole Juul]

Aren't degaussers a bit on the expensive side?

Tape degaussers are pretty simple and Radio Shack sells (still?) a cheap one. You could probably make one because it's just a coil with an optional switch. Check Google images to see fancy ones for studio use. The desk models for 10" reels or 2" tape are expensive but the hand held VHS ones are really simple and can be used for everything - including a 10" pancake. I have one from the thrift shop and it was only a couple of bucks. There is one on eBay right now for forty bucks but you shouldn't have to pay that much. For audio tape recording they used to be essential because you can't otherwise reuse tape unless you are willing to put up with background noise.