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View Full Version : Floppy drive not working on XT clone



vq304
October 16th, 2005, 04:13 AM
I have an XT clone here (ITT Xtra) which doesn't seem to want to read a floppy drive correctly. Unfortunately I can't find any documentation about the computer at all, so I don't know what any of the jumper settings do.

The drive I'm using is a 1.2MB 5.25" drive. The computer has what appears to be one floppy connector on the motherboard, and 2 on an expansion card (labelled J1 and J2). Obviously they're not all going to be for floppy drives, but the connection looks the same.

Plugging the drive into the one on the motherboard causes the motor in the drive to spin when the computer tries to boot, but the drive LED does not come on. It then gives the error 'drive not ready'.

Using J1 on the expansion card causes the motor to spin and the LED comes on, but gives the same error.

Using J2 does the same as the motherboard one - motor spins but no LED.

An XT clone would be compatible with a 1.2MB drive, wouldn't it? What would be causing this issue - jumper settings or something? If so, does anyone have any idea how I can set it up properly?

Thanks for any help.

Jorg
October 16th, 2005, 06:04 AM
An XT clone would be compatible with a 1.2MB drive, wouldn't it?

Most likely: NO

1.2 MB drives were for AT's and up.

vq304
October 16th, 2005, 07:34 AM
Oh, well that's a bit simpler than what I expected then.

In other words, the only drive that will work is a 360KB 5.25"? It'll be pretty hard to find one of those where I live :(

Terry Yager
October 16th, 2005, 08:28 AM
Check the device select jumpering on the drive too. If it's a pull from a PC or clone, it's probably set-up as device #2, but your not-quite-clone may be wanting device #1.

--T

Mad-Mike
October 16th, 2005, 03:52 PM
A few answers....

First off, if you don't have a twist in the floppy cable, you will probably have to set the drive to drive select 0 (DS0 is what it's usually marked). Some early XT clones did not have the twist, but so far all the XT's I've worked with work with a twist in the cable just as good as any x86 based PC I've seen.

Second, most XT clones are not compatible with 1.2M floppy drive because it came afterward (they were introduced on the IBM 2570 AT in 1984). Judging by it being an ITT Extra, and being as I saw it in a classic computer collectors guide I got way back in 1997, it's probably not compatible with that drive (I think it was circa 1983, I'd have to go back and check).

vq304
October 16th, 2005, 10:43 PM
I found a little bit of information about it on Google. Apparantly it was released in 1984, and came with a 360KB floppy drive (2x 360KB drives optional).

There are 4 jumper settings on the drive I'm using here, labelled from D0 to D3. I don't know if they're anything to do with drive select, but it's the closest thing I can find. D1 originally had a jumper cap on it, but I removed it and put it on D0 instead. It didn't make a huge difference, still can't get it to boot from the drive.

Tried a couple of different floppy cables (all with the twist), and they give the same result.

It's a shame, I spent months looking for an XT and this was the only one I could find. If it requires a 360KB drive then it's pretty much junk, I'd have to buy one from America or something and get it posted over (ie. far too much money).

Terry Yager
October 16th, 2005, 11:55 PM
With a twist in the cable, the drive should be jumpered as D1 (if the numbering is D0 - D3).

--T

Anonymous Coward
October 24th, 2005, 08:09 PM
The 1.2MB drive will not work in the system unless you have a special high-density floppy controller which you can still buy from JDR Electronics. I just ordered one today as a matter of fact. They're a little pricey though. $29 and $10 shipping.

lither
November 4th, 2005, 07:51 AM
It's a shame, I spent months looking for an XT and this was the only one I could find. If it requires a 360KB drive then it's pretty much junk, I'd have to buy one from America or something and get it posted over (ie. far too much money).
Have you try 1.44 M drive?
i have heard that most XT controller treat the 1.44M drive as 720K drive
therefore, if you are lucky enough you can hook a 1.44 M drive and use it as 720K drive
besides, 3.5 disk is more stable than the 5.25 disk

vq304
November 15th, 2005, 08:43 PM
Have you try 1.44 M drive?
i have heard that most XT controller treat the 1.44M drive as 720K drive
therefore, if you are lucky enough you can hook a 1.44 M drive and use it as 720K drive
besides, 3.5 disk is more stable than the 5.25 disk

Nope, I haven't, but I did try an actual 720KB drive and it didn't work.