Installing Teac 55B 5.25/360kb FDD - UK Vintage Radio Repair and Restoration Discussion Forum

HMV 1120 · 10th Feb 2010, 9:48 pm

I have the above mounted in my second machine after the cable twist as 'A:/' and jumpered to D.1

The machine runs XP and fails to recognise it has a 5.25" drive, instead stating it to be 1.44mb 3.5" instead. The drive does atleast appear to function correctly -it only lights up and the disk spins when selected from 'my computer'. However I always receive an 'insert disk into drive a:/' prompt.

Well I thought, the obvious thing to do is change the drive entry in the CMOS bios at setup. Unfortunately, it only has options for 3.5" drives (720k,1.44mb,2.88mb).

Are there any ways around this or is the machine (2004 Compaq Presario S000) simply too new/drive too obselete? Would changing to an older OS e.g. Win98 do the trick?

Regards,
Robs.

cmjones01 · 10th Feb 2010, 10:58 pm

As far as I know, there's no way for the PC to tell what kind of floppy drive is attached. The interface to the drives just isn't that sophisticated, which is why there's a setting in the BIOS to define what kind each one is.

It sounds like Windows is just observing what the BIOS is telling it, and the BIOS denies the existence of 5 1/4" drives, which isn't that surprising for a 2004 machine. I don't know of a way of telling Windows otherwise.

Under Linux, it certainly used to be possible to force floppy drives into particular modes by using different device names: /dev/fd0u1440 for 1.44M 3 1/2", /dev/fd0d360 for 360k 5 1/4", and /dev/fd0h1200 for 1.2M 5 1/4". Even that may be somewhat dependent on the BIOS and disc controller, though.

Chris

cmjones01 · 10th Feb 2010, 11:16 pm

I've just tried a quick experiment on an elderly PC here, which uses an Asus A7V motherboard which dates from the year 2000. It has a 3 1/2" floppy drive, but I set it to be 5 1/4" in the BIOS setup. Windows XP boots and happily shows drive A: as 5 1/4", so XP definitely supports 5 1/4" drives.

Chris

paulsherwin · 10th Feb 2010, 11:26 pm

Double check that you have connected the drive correctly. It's easy to get this wrong, especially with these old drives with edge connectors and convoluted cables.

When you try to access the drive, you should see the red LED come on. Is this happening? If not, there's probably some cabling problem.

You can certainly use this drive with Linux irrespective of the BIOS settings, but I think all the Windows versions take their FD geometry numbers from the BIOS. Booting a CD Linux or setting up a dual boot system may be one solution if you want to mostly stay with Windows.

Paul

dseymo1 · 12th Feb 2010, 8:48 pm

Drive types can be 'forced' in MS-DOS, too, but I'm afraid I can't remember the syntax to do so. Perhaps this function is still available via the 'command prompt' in Windows - I don't know.

Dave Moll · 12th Feb 2010, 9:48 pm

There seem to be two separate issues here.

1) The computer thinks that the drive is B:. If I am remembering correctly, a drive set internally as "0" will be recognised as "A:" after the twist or "B:" before it. This is reversed if the drive's jumper is set to "1". Your description in the initial post seems to be saying that you have set to "1" after the twist, so it is correct in considering it to be drive B: (hence the "insert disk for drive A:" message). If you either move the drive to before the twist or set the jumper to "0", it should be recognised as A:.

2) The BIOS does not have a setting for 5¼" discs. This should not be a problem for accessing the disc. It may, however, require a certain degree of deviousness to format a disc correctly, if possible at all. Using the DOS format command with something like "/s=360" (like dseymo1, I can't remember the exact format offhand) might have the desired effect.

fidobsa · 16th Feb 2010, 1:20 pm

Information about using the format command in DOS can be found here:
http://www.computerhope.com/formathl.htm

llama · 18th Feb 2010, 6:29 pm

Some early PCs didn't have a setup function as such, you had to run a program that does the setup in CMOS for you.
I mention this because I can remember rustling up an old PC once where its CMOS allegedly didn't support the drive I wanted to fit. I ran the CMOS setup program and selected the drive type and then the higher levels (DOS, Windows) saw it fine. I guess the values in the CMOS are read rather than the text interpretation of them, if that makes sense.
Please don't ask me to find the program; it must be downloadable from somewhere...
Regards
Graham

Dave Moll · 18th Feb 2010, 7:53 pm

Quote:

Originally Posted by llama

you had to run a program that does the setup in CMOS for you.

...

Please don't ask me to find the program; it must be downloadable from somewhere.

If anyone needs a copy and can't find one to download, I have a copy on my 286 AT.

cmjones01 · 18th Feb 2010, 11:10 pm

I'd be a little surprised if any machine built in 2004 needed a disk-based CMOS setup program, but stranger things have happened. Especially with Compaqs!

HMV 1120 · 20th Feb 2010, 9:26 pm

Apologies all for the delay - Geology fieldwork courses (curses?) on the Isle of Arran are not conducive to IT communication.

I'll play with the jumper settings this week and see if it makes a difference. I have MS - DOS 6.22 lying around if all else fails (dir a:/ anyone?)

Robs

10th Feb 2010, 9:48 pm	#1
HMV 1120 Hexode Join Date: Jan 2007 Location: Weeting, Norfolk. Posts: 465	Installing Teac 55B 5.25/360kb FDD I have the above mounted in my second machine after the cable twist as 'A:/' and jumpered to D.1 The machine runs XP and fails to recognise it has a 5.25" drive, instead stating it to be 1.44mb 3.5" instead. The drive does atleast appear to function correctly -it only lights up and the disk spins when selected from 'my computer'. However I always receive an 'insert disk into drive a:/' prompt. Well I thought, the obvious thing to do is change the drive entry in the CMOS bios at setup. Unfortunately, it only has options for 3.5" drives (720k,1.44mb,2.88mb). Are there any ways around this or is the machine (2004 Compaq Presario S000) simply too new/drive too obselete? Would changing to an older OS e.g. Win98 do the trick? Regards, Robs. __________________ Real radios glow in the dark M6GLD

10th Feb 2010, 10:58 pm	#2
cmjones01 Nonode Join Date: Oct 2008 Location: Warsaw, Poland and Cambridge, UK Posts: 2,677	Re: Installing Teac 55B 5.25/360kb FDD As far as I know, there's no way for the PC to tell what kind of floppy drive is attached. The interface to the drives just isn't that sophisticated, which is why there's a setting in the BIOS to define what kind each one is. It sounds like Windows is just observing what the BIOS is telling it, and the BIOS denies the existence of 5 1/4" drives, which isn't that surprising for a 2004 machine. I don't know of a way of telling Windows otherwise. Under Linux, it certainly used to be possible to force floppy drives into particular modes by using different device names: /dev/fd0u1440 for 1.44M 3 1/2", /dev/fd0d360 for 360k 5 1/4", and /dev/fd0h1200 for 1.2M 5 1/4". Even that may be somewhat dependent on the BIOS and disc controller, though. Chris

10th Feb 2010, 11:16 pm	#3
cmjones01 Nonode Join Date: Oct 2008 Location: Warsaw, Poland and Cambridge, UK Posts: 2,677	Re: Installing Teac 55B 5.25/360kb FDD I've just tried a quick experiment on an elderly PC here, which uses an Asus A7V motherboard which dates from the year 2000. It has a 3 1/2" floppy drive, but I set it to be 5 1/4" in the BIOS setup. Windows XP boots and happily shows drive A: as 5 1/4", so XP definitely supports 5 1/4" drives. Chris

10th Feb 2010, 11:26 pm	#4
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,943	Re: Installing Teac 55B 5.25/360kb FDD Double check that you have connected the drive correctly. It's easy to get this wrong, especially with these old drives with edge connectors and convoluted cables. When you try to access the drive, you should see the red LED come on. Is this happening? If not, there's probably some cabling problem. You can certainly use this drive with Linux irrespective of the BIOS settings, but I think all the Windows versions take their FD geometry numbers from the BIOS. Booting a CD Linux or setting up a dual boot system may be one solution if you want to mostly stay with Windows. Paul

12th Feb 2010, 8:48 pm	#5
dseymo1 Retired Dormant Member Join Date: Dec 2007 Location: Shropshire, UK. Posts: 3,051	Re: Installing Teac 55B 5.25/360kb FDD Drive types can be 'forced' in MS-DOS, too, but I'm afraid I can't remember the syntax to do so. Perhaps this function is still available via the 'command prompt' in Windows - I don't know.

12th Feb 2010, 9:48 pm	#6
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,127	Re: Installing Teac 55B 5.25/360kb FDD There seem to be two separate issues here. 1) The computer thinks that the drive is B:. If I am remembering correctly, a drive set internally as "0" will be recognised as "A:" after the twist or "B:" before it. This is reversed if the drive's jumper is set to "1". Your description in the initial post seems to be saying that you have set to "1" after the twist, so it is correct in considering it to be drive B: (hence the "insert disk for drive A:" message). If you either move the drive to before the twist or set the jumper to "0", it should be recognised as A:. 2) The BIOS does not have a setting for 5¼" discs. This should not be a problem for accessing the disc. It may, however, require a certain degree of deviousness to format a disc correctly, if possible at all. Using the DOS format command with something like "/s=360" (like dseymo1, I can't remember the exact format offhand) might have the desired effect. __________________ Mending is better than Ending (cf Brave New World by Aldous Huxley)

16th Feb 2010, 1:20 pm	#7
fidobsa Retired Dormant Member Join Date: Mar 2009 Location: Zala, Hungary Posts: 418	Re: Installing Teac 55B 5.25/360kb FDD Information about using the format command in DOS can be found here: http://www.computerhope.com/formathl.htm

18th Feb 2010, 6:29 pm	#8
llama Octode Join Date: Jun 2006 Location: St Osyth, Nr Clacton, Essex, UK. Posts: 1,482	Re: Installing Teac 55B 5.25/360kb FDD Some early PCs didn't have a setup function as such, you had to run a program that does the setup in CMOS for you. I mention this because I can remember rustling up an old PC once where its CMOS allegedly didn't support the drive I wanted to fit. I ran the CMOS setup program and selected the drive type and then the higher levels (DOS, Windows) saw it fine. I guess the values in the CMOS are read rather than the text interpretation of them, if that makes sense. Please don't ask me to find the program; it must be downloadable from somewhere... Regards Graham

18th Feb 2010, 11:10 pm	#10
cmjones01 Nonode Join Date: Oct 2008 Location: Warsaw, Poland and Cambridge, UK Posts: 2,677	Re: Installing Teac 55B 5.25/360kb FDD I'd be a little surprised if any machine built in 2004 needed a disk-based CMOS setup program, but stranger things have happened. Especially with Compaqs!

20th Feb 2010, 9:26 pm	#11
HMV 1120 Hexode Join Date: Jan 2007 Location: Weeting, Norfolk. Posts: 465	Re: Installing Teac 55B 5.25/360kb FDD Apologies all for the delay - Geology fieldwork courses (curses?) on the Isle of Arran are not conducive to IT communication. I'll play with the jumper settings this week and see if it makes a difference. I have MS - DOS 6.22 lying around if all else fails (dir a:/ anyone?) Robs __________________ Real radios glow in the dark M6GLD