View Full Version : Floppy Drive Failure

Russell D
17-03-2003, 11:53 PM
I bought a Sony floppy drive off Trademe to replace a dead unit.
When plugged into a P3 ATX m/b the drive light is permanently on and the drive is not recognised.
The seller claims it was working perfectly when shipped.

There is a block of jumpers on the drive, but no manual available.
Is the light permanently on the symptom of a known fault?

Any help appreciated.

18-03-2003, 12:09 AM

Check to see that the IDE cable is on the correct way round. The light being on permantly is a symptom of this (I think) :)


18-03-2003, 12:11 AM
Also are you getting a floppy drive error (40) at the POST?

18-03-2003, 02:55 AM
you can rotate the floppy cable 180 degrees without doing any damage to the drive and see if this works. The light hard on is a sign that your cable is around the wrong way. also make sure that your cable has the red edge connected to the pin 1 on the M/Bd, this is either a 1 close to one end or a coloured triangle at one end to indicate pin 1.

Russell D
18-03-2003, 06:55 AM
There are guides on the cable ends and matching cut-outs on the m/b connector and drive so you can't plug it in any other way.

Graham L
18-03-2003, 03:49 PM
Russell: Try another cable. It is an infallible indication of a wrongly connected cable that the light is on all the time.

Floppies use "open collector" control and data lines. If the line is pulled low (ground), that is a logic 1. One row of the two is connected to ground. If the cable is flipped, all the data and control lines are earthed. The drive is selected (and all the control lines are on, too), so the select light is on. It won't work like that. :D

If you can't find another cable, you can file off the key on one of the connectors. Manufacturers don't always follow standards. Sometimes, they have a cockup, and make their own "standard".

Russell D
19-03-2003, 10:51 PM
Thanks Graham, grinding the guide off cable end and reversing the connector made the drive operable.

I have another drive which the light stays on continually, but no amount of cable gymnastics will make it work.

Graham L
20-03-2003, 05:36 PM
Of course, if the cable is correctly oriented, the select light on all the time can indicate a fault in the drive electronics (or the interface).

But I always assume the cable is wrong first, because (1) that's the "simplest" (and therefore cheapest) diagnosis, and (2) it's the most common fault. :D

As well as the 180 degree flip, some drives don't have a housing on the coinnector, and it's possible to have the cable plugged on 1 or 2 pins sideways. That doesn't work very well either. ;-)