The help would be from the computer types, the cry for it is from me.

One of the reasons I haven't been posting much is because I'm taking care of some things that have been neglected for a while, one of which is putting a floppy back into my server that hasn't had one for a while.

I've got two drives and two cables to play with. The connectors are keyed and will only go on one way (presumably, the right one, and it's consistent with the IDE cables in terms of pin one).

I cannot get the light to go off on the drive. It comes on when powered up, and I get a floppy failure at POST. I know that this is usually a symptom of reversed cables, but there's no way to get it wrong. I've tried it with both drives and both cables, and both connectors on both cables, with always the same result. The only common factor is the MB. Would a FD controller problem display this symptom? I hate to replace a MB without knowing for sure, but I can't imagine where else the problem could be.

Unfortunately, my experience as a computer dumpster diver has been that the floppy controller is typically the first thing which goes on a mother board. Due to the antiquity of the standard, motor power is being switched. Best thing to do would be to test the drives in some other computer; if at least one of them works then it is for sure the mobo.

Well, it's not exactly an antique board--it's running a Duron 750, FWIW, and could handle an Athlon. It's only a couple years old.

Another dumpster diver here.

I assume that "The connectors are keyed and will only go on one way" means the "notch" in the socket and the raised "key" of the cable plug, or the block in the old style edge connector that some floppy drives have.

Make sure you're *not* using an old MFM/RRL/ESDI HD drive cable instead of a floppy cable (they have the same # of pins). The twisted lines in a floppy cable are *nearest* pin #1, the striped edge of the flat cable. On the old HD cables the twist is on *opposite* side from pin #1.

Also, floppy drive #1 is the plug downstream from the twist. #2 plug is upstream (toward the controller) from the twist. If you're just installing one floppy drive, make sure the twisted lines are between the floppy and controller.

It is also possible to reverse the power plug on some floppy drives without realizing it. If the power plug and socket are the old (and big) bevel keyed Molex type, it's almost impossible. But the mini-plugs used on 3.5" floppy drives can be reversed accidently if you apply a little force. The drive light not going out can be a symptom, along with the drive not being recognized.

The raised "key" in the mini power plug should be *away* from the PC board in most floppy drives I've seen. If you hold the drive right side up, looking at it from the top, and from *behind*, the RED power line will be on the right, the YELLOW on the left. The "key" in the power plug is nearest the RED line.

HTH

I agree with triticale..we have the same thing happen with older Compaq SFF PC's that are on the manufacturing floor..take the drive out and test it on a known good PC..as for the MB not being an antique, maybe not, but we all know that sh*t happens.

Gupps

It sure does sound like reverse polarity to me. That floppy plug can easily be put in upside down... flub is right.

Find an unnotched cable, or examine it real closely and make sure it has no choice but to go the way you're putting it. But a floppy cable, even without the key notches in the plastic, will have a spot where a pin is missing so it'll only plug one way. It's really easy with a floppy cable to think it'll only fit one way when it needs to go, and can go, the other way. Been there, done that, many times.

If you're absolutely sure the cable isn't bad or flipped on one end, then yes, it most likely is the FDD controller. I think it could be the drive too; trying to remember if I have ever seen that happen, and am not sure.

Make sure your *power cable* is right. I've seen that before with a power cable that was on 3 of the 4 pins.

Don't forget to flip the cable over, if its upside down, that's a problem. I've seen cables that didn't block off. Best thing, get where you can find where the motherboard says "1 or pin 1" and make sure the red on the cable is there. Then do the same with the drive.

Addson

Addison, I started a fire in my PC like that once. It was only on 3 of the 4 pins, and as soon as i turned it on (with the case off, thank God!), it started to smoke and then quickly flame.

*cowers in shame at the memory*

"It" being the floppy drive power cable (that wasn't clear, upon further review). It was my first home-built PC (for myself, thankfully).

The Mobo is clearly marked and keyed (and consistent with the IDE cables, which work). There's no way to tell which is pin 1 on the drive, but there's also no way to put the connector on both ways--the pins are too close to the board to put the key on the bottom. It really will only go on one way. As I said, two cables, two drives, and no combination of them will work--the light stays on.

It really does seem like it must be a MoBo problem. The only thing that I haven't done is to verify drives and cables in another machine.

Once I was building a system and accidentally put a metal standoff in an incorrect position for the motherboard I was installing. The standoff shorted some signals on the FDD connector, and the symptom was a FDD that would not complete initialization (FDD spun constantly and FDD light did not go off).

P.S. I forgot to say that once the standoff was repositioned, the system worked fine, including FDD. "Shorting" has such an alarming connotation to some that I figure I should mention that if the affected circuitry did not die within the first second, it will most likely last for the useful life of the motherboard.

Rand:
In my experience, a steady light on a FDD is the result of inserting the LED power connector backwards. Try it the other way....the Power connector and IDE cable are probably OK as is.

Bill
St. Paul, MN

If you don't mind a thought from a Mac user, try the floppies one at a time in the a: ( beyond the twist position. If one works and the other doesn't, it's a drive problem. If both work, then its the cable. If neither works it could be anything, including the mobo. Yes, I do help put pcs together and prefer Macs.
It took many cable combinations to get a pc I helped with to recognise 2 drives. They seem yo have a built in dislike of a second floppy. Good luck.

Rand wrote: "There's no way to tell which is pin 1 on the drive..."

There is, but it takes a bit of work. Look at the soldered side of the drive's PC board. The pad for pin #1 controller connector is usually a different shape from the pads for the rest of the pins. Usually pin #1 pad is square and the rest are round.

Sometimes pin #1 is marked with a text "1" (or pin #2 with a "2") painted on the board. Sometimes the painted mark will be just a shape, like a triangle pointing to pin #1. That painted mark may be on either side of the drive's PC board.

But I'm beginning to suspect an upside-down power connector, because it's fairly easy to do, and because I've done it and gotten exactly the same symptoms: no drive recognition and drive light always on with motor always spinning.

Definitely test the drives on another MoBo before you toss either the MoBo or the drives. 1.44 Mb drives are very cheap these days though. I've bought them new for as little as $3 at flea markets or even store sales.

Also, if the MoBo built-in FDD controller is bad, you can install an old FDD controller in an ISA slot, and just turn off the MoBo's FDD controller in the BIOS.

HTH.

Rand,

the symptoms you describe are consistent with a reversed data cable. Every drive I've ever used in a PC was keyed so that pin one was closest to the power connector; if you plug the cable in so that the red stripe is closest to the power plug, it should work.