# OLD floppy problem (5 1/4)

## zombor

OK, I got these very old 5 1/4 floppies someone needs info from (dont ask why, i dont know). So i ebayed a drive and hooked it up to my windows machine, and when i click on the drive, it give me some crazy error message, so i decided to try it out in gentoo.

I booted off the liveCD and 

```
ls -l /dev/fd*
```

No results.

So then I modprobe floppy, and I get a /dev/fd0 and a /dev/floppy along with:

```
#dmesg | grep fd

Floppy drive(s): fd0 is 1.44M
```

However, this is a 1.2Mb 5 1/4 drive...I cannot mount the disk, I assume because it thinks its something its not. Is there something I have to do to get this old ass hardware to work? A different module? Anything?

----------

## Nijinski

You did remember to go into the BIOS and tell your machine it was a 1.2 drive ?

----------

## NeddySeagoon

zombor,

There are two different interfaces for 5 1/4" drives. They look the same but one will not work in a PC.

I forget the details now, something to do with the media change signal I think. If you have a non PC drive. It cannot be made to work.

To add to the fun, 5 1/4" drives came in 360km 720k and 1.2Mb.

----------

## zombor

Yes, it is recognised in BIOS as a 1.2Mb 5 1/4 drive.

I got a special floppy cable for it that has both the old "card" interface for 5 1/4 drives, and regular 3 1/2 drives as well.

Do the disks have to match the capacity of the drive?!? I am old-school, but I havent even seen a 5 1/4 in like 15 years...

----------

## pilla

A 1.2 MB 5 1/4 drive? I don't remember having heard of one of these.......

----------

## zombor

 *pilla wrote:*   

> A 1.2 MB 5 1/4 drive? I don't remember having heard of one of these.......

 

Because it's been that long  :Wink: 

----------

## NeddySeagoon

zombor,

You can read any of the lower capacity 5 1/4" floppies in a 1.2Mb drive.

Writing lower capacity disks is a bit involved and depends on where they were formatted and where you want to read them afterwards.

1.2Mb drives have half the track width of the lower densities. When you write a 720kb floppy, that was formatted in a 720kb drive, it writes down the middle of the wider track. This track now has old data at the outside and new data in the centre. Your 720kb drive can no longer read that part of the floppy ...

----------

## AaronPPC

If you get it to work you have to tell us how sloooow it seems.

The nice thing about 5 1/4" disks was that you never had to explain to anyboday why their called floppies.

----------

## zombor

 *NeddySeagoon wrote:*   

> zombor,
> 
> You can read any of the lower capacity 5 1/4" floppies in a 1.2Mb drive.
> 
> Writing lower capacity disks is a bit involved and depends on where they were formatted and where you want to read them afterwards.
> ...

 

All I need to do is read the disks that I have. No writing. it would be nice to see if i could format a new disk, but I have no blanks or extras to work with  :Sad: 

----------

## NeddySeagoon

AaronPPC,

1.2 Mb 5 1/4 floppies are the same speed as 1.44Mb 3 1/2

So you know how slow it is.

----------

## DaveArb

 *zombor wrote:*   

> All I need to do is read the disks that I have. No writing. it would be nice to see if i could format a new disk, but I have no blanks or extras to work with 

 

If you're relatively close to middle USA, I could throw some in the mail at you. If you're a long way away, it would probably take so long as to not be interesting. PM if interested, I'm sure I still have bunches of the darn things. Probably have DSDDs too.

@Pilla, 5.25" 1.2MB floppy is "high density double sided." Why do I remember all this stuff, but cannot remember my phone number?

NeddySeagoon mentioned 360, 720 and 1.2MB 5.25". I only recall 720K in 3.5, that's a single sided version of the 1.44M. But, I do remember 180K single sided 5.25, and DEC's strange single sided 400K 5.25".  :Wink: 

Dave

----------

## pilla

 *DaveArb wrote:*   

> 
> 
> @Pilla, 5.25" 1.2MB floppy is "high density double sided." Why do I remember all this stuff, but cannot remember my phone number?
> 
> 

 

Of course, I was just confused -- thought that it was 1.44 but 1.44 is for 3.5"

----------

## zombor

 *DaveArb wrote:*   

> 
> 
> NeddySeagoon mentioned 360, 720 and 1.2MB 5.25". I only recall 720K in 3.5, that's a single sided version of the 1.44M. But, I do remember 180K single sided 5.25, and DEC's strange single sided 400K 5.25". 
> 
> Dave

 

The disks that I have say 500K on them. If i hook this drive up to an already installed gentoo system, will it automagicly detect it? maybe the liveCD doesnt like me.

----------

## DaveArb

I think 500K are double-sided double-density (360K formatted), not high density 1.2MB formatted/2MB unformatted. Back when I worked with floppies, SCO UNIX required different /dev/ files for each different format. I'm afraid I don't know how they work in Linux.

Dave

----------

## jschellhaass

The good ole days

SSSD - Single Sided Single Density 90k - Atari 800 - Anyone remember Elephant disks and notching'em with a paper punch for double sided use?

SSDD - Single Sided Double Density 180k

DSDD - Double Sided Double Density - 360k

I'll have to see if I still have a 5.25 drive laying around and see if works under Gentoo.

jeff

----------

## NeddySeagoon

DaveArb,

Linux required different /dev/ entries for formatting floppies but they should all read and write on same one provided they use standard formats. Linux supports other block sizes than 512b and up to 82 tracks, which some floppies can do too.

Reading and writing to such nonstandard formats is the users problem.

I still have a 5 1/4"  1.2 Mb drive and some blank media to play with. 've not used it for about 5 years.

I was wrong about the 720kb being a 5 1/4" format. It was 180kb, 360kb and 1.2 Mb

----------

## zombor

 *NeddySeagoon wrote:*   

> 
> 
> I was wrong about the 720kb being a 5 1/4" format. It was 180kb, 360kb and 1.2 Mb

 

There must have been 500K disks as well, since that is what mine say on them. The person I got it from says they were from an old 386 with Word Documents on them. Must have been windows 3.11? I tried the drive in Win95 and had no luck either. Perhaps I purchased a defective drive  :Sad: 

----------

## NeddySeagoon

zombor,

500k is the unformatted size, (1.44Mb disks are marked 2Mb) It sounds like they are 360kb (formatted) disks.

Windows 3.11 or a 386? 

Maybe. More likely Word for DOS (I rememebr Version 5.0)

A 386 would have had a 1.2Mb drive, it may have had a 1.44Mb drive too. If you have obtained a 360kb drive, it would not read 360kb disks formatted in a 1.2Mb drive because the tracks are only half the width they need to be.

----------

## zombor

 *NeddySeagoon wrote:*   

> 
> 
> A 386 would have had a 1.2Mb drive, it may have had a 1.44Mb drive too. If you have obtained a 360kb drive, it would not read 360kb disks formatted in a 1.2Mb drive because the tracks are only half the width they need to be.

 

I have a 1.2Mb drive, will it read any size disks formatted in any size drive?

----------

## NeddySeagoon

zombor,

Yes. A 1.2Mb drive will read the mess created by mixed writes to 360kB media.

When you attempt to mount a floppy, the drive should spin up does it?

A few other anachronisims to check.

A floppy controller supports 4 drives but in PCs fitted with hard drives only two are used.

Floppy cables fitted to most modern systems have 4 wires split out of the ribbon and twsted between one drive connecot and the other. This twist swaps over the drive select lines for drives A:\ and B:\. It means that the drives are always jumpered as drive A:\ but the position determines which drive they respond as.

Older systems (no twinst in the drive select lines) needed the floppy drives to be jumpered, and 5 1/4 drives were provided with a 4 way header and jumper (fit one) to choose if the drive should respond as A, B, C, or D.

Assembling parts today, you will have a drive with the drive select jumper and a cable with the twist. If the drive is not jumpered as drive A:\, it will not work at all with a cable with a twist.

----------

