old 5.25" floppy driver's jumpers - Page 1
Forum section: electronics / general

author: legacy
author_rank: Super Contributor
timestamp: March 29, 2019, 05:33:26 pm
content: So, a few days ago I sold an old 5.25" floppy-driver to a dude. The unit was pulled out from a working system. And when I say "working system" I mean that I have recently used that 586 PC for reading a couple of 5.25" floppies. Everything worked, except the floppy cable was a bit weird, the kind of story where you cannot trust the "locker": that piece of plastic step that prevents you from inserting a cable in the wrong way. For some odd reason, that step was on the wrong side. Anyway, once you know it, then it works! 5.25" floppy drivers also have "some twist wires", which serve to select how the first, before twist, and second drive, after the twist ... something that DOS calls "A:" or "B:"Anyway, the dude who bought the floppy driver didn't even think about the inverted cable and he started playing with jumpers ... making a mess.Now he doesn't remember the original position of jumpers on the floppy-driver-controller board, and ... I have no manual for my driver, probably lost in time ( I bought that driver in 1994).Googling, I foundthisdoc, which is nice because the model is exactly the same floppy driver, but the doc doesn't look clear to me.can anyone save us?

author: ebastler
author_rank: Super Contributor
timestamp: March 29, 2019, 06:04:14 pm
content: Hey, I have one of those drives (TEAC FD-55GFR 149-U5). Actually the only 5.25" drive I have retained. It's in storage at the moment, but was taken from my own working PC, many moons ago... FWIW, here's how the jumpers are set:- D1- DC (connect the one "outlying" pin in this group of pins to its nearest neighbor)- FG (the lonely two pins at the far end of the board, behind the power jack)Hope this does the trick... I believe this was last running as the sole drive in a 486 PC. Although the jumper on "D1" instead of "D0" might mean it was a second drive; maybe a 3.5" drive was wired to D0.BTW, I like the new logo on the DTB site!

author: helius
author_rank: Super Contributor
timestamp: March 29, 2019, 06:11:27 pm
content: The jumpers on PC floppy drives were never changed to switch from A: to B:. Instead they were placed on different ends of the cable, which had a part twist in it as legacy said. I think they were always jumpered for disk#1 ("B:") and the A: drive was the one that received the cable twist.

author: German_EE
author_rank: Super Contributor
timestamp: March 29, 2019, 06:26:00 pm
content: I might be able to help here but it has been a long time since I worked on floppy drives and memories fade.1) The PCB on the drive and the stripe on the cable indicate pin 1, if you connect a cable the wrong way around the motor will continuously turn but no damage will be done.2) On every drive the drive address MUST be set to 1, drive selection is via the twist in the cable with drive A at the end and drive B on the middle connector without the twist.3) The LG jumper should not be fitted.4) Your drive should not normally have the I jumper fitted, this means that all disks rotate at 360 rpm. If you can read 360K disks bit not 1.2Mb disks (or the other way around) then fit this jumper.5) Only fit jumper E2 if your machine is an older IBM PC or IBM PC XT6) For an IBM AT system and above jumpers 1U, U0 and U1 should not be fitted. There are only five usable combinations out of nine here if you get stuck, none, 1U, 1U+U0, U0+U1 and 1U+U0+U1. All other combinations are invalid.7) The DC jumper should be fitted.Terminators on drive A may be needed.How old is this information? The pages of my notes in the garage were yellow and faded, time marches on.

author: Braniegk
author_rank: Newbie
timestamp: March 29, 2019, 06:48:26 pm
content: Hi everyone! I'm the guy who bought the floppy drive.I want to use it on a PC AT and as a second floppy drive (the first must be the 3,5).I would like to read and write 1,2 MB disk. How should I configure the jumpers then?Thanks for all!

author: soldar
author_rank: Super Contributor
timestamp: March 29, 2019, 08:57:14 pm
content: Just a while ago I was clearing crates of old stuff to get rid of and I have a 5.25" Safronic DS-53A drive plus other 3.5" drives, cables of all (old) sorts, etc. They are yours if you want them. Where are you located?

author: Red Squirrel
author_rank: Super Contributor
timestamp: March 29, 2019, 09:03:54 pm
content: Oh wow been a while I played with that stuff.I do recall HDDs had master/slave jumpers as well as cable select, and think one for cylinder limitation once large drives started to come out (100GB etc). Don't remember ever having to mess with floppy ones though...

author: shteii01
author_rank: Frequent Contributor
timestamp: March 30, 2019, 02:36:22 am
content: Quote from: Braniegk on March 29, 2019, 06:48:26 pmBasically. You never touch the jumpers.Like helius wrote. The floppy drive cable had three connectors. Two of the three connectors are closer together, this end of the cable went to floppy drives. The connector on the very end was the Drive A, always. The connector in the "middle" of the cable was Drive B. The connector on the other end plugged into mobo/controller card.

author: shteii01
author_rank: Frequent Contributor
timestamp: March 30, 2019, 02:46:27 am
content: This might help to put jumpers where they belong:https://drive.google.com/file/d/0B2TmWnRjWCj2SVMxQjBsdEVNREk/edit

author: drussell
author_rank: Super Contributor
timestamp: March 30, 2019, 02:56:29 am
content: That cable shown by the OP doesn't even make any sense. 5.25" drives use a card-edge connector, not a pin header.I have dozens of 5.25" drives here. What make is it? Panasonic? Teac? Mitsumi? Sony?If you let me know what it is, preferably with the actual model number, I can pull one out and let you know for sure. The older the drive is, the more likely it is to have more jumpers for various obscure (for the PC world) settings. It mayworkwith some things set somewhat incorrectly but better to set it all to where it should be on a PC.

author: drussell
author_rank: Super Contributor
timestamp: March 30, 2019, 02:58:16 am
content: Quote from: shteii01 on March 30, 2019, 02:36:22 amDude, that's an IDE cable, (and a modern 80-pin one at that,) not a floppy cable of any sort.

author: drussell
author_rank: Super Contributor
timestamp: March 30, 2019, 03:12:51 am
content: Quote from: German_EE on March 29, 2019, 06:26:00 pmUnless you have a disk in there....Many drives will write glitch the track that is under the head when you have the cable backwards.It is best practice to always power up a newly-cabled floppy drive for the first timewithout a disk in itto ensure you don't destroy the data on (usually track 0)!

author: shteii01
author_rank: Frequent Contributor
timestamp: March 30, 2019, 04:24:58 am
content: Let me dig up some card-edge connector cables for you.Here we go. This is "universal" one. Works with both, 5.25 and 3.5 floppy drives.

author: Braniegk
author_rank: Newbie
timestamp: March 30, 2019, 09:57:20 am
content: Quote from: drussell on March 30, 2019, 02:56:29 amSure! it's a Teac FD 55 GFR 149 U5

author: legacy
author_rank: Super Contributor
timestamp: March 30, 2019, 12:15:34 pm
content: Quote from: Braniegk on March 30, 2019, 09:57:20 amHis 5.25" driver has a soldered PIN connector, the same used by 3.5" floppy drivers.It was a hack, I suppose.

author: ebastler
author_rank: Super Contributor
timestamp: March 30, 2019, 12:30:38 pm
content: Quote from: legacy on March 30, 2019, 12:15:34 pmCan we agree that these things are called floppydrives? "Drivers" is a tad confusing. When I read the original post, I first thought you were talking about the PC-side interface board.

author: ebastler
author_rank: Super Contributor
timestamp: March 30, 2019, 01:33:28 pm
content: Quote from: legacy on March 30, 2019, 12:35:18 pmNever mind. I have seen in the DTB thread how you flew in everyone’s face, then quietly took our advice. So there’s hope.

author: Simon
author_rank: Unknown
timestamp: March 30, 2019, 01:47:12 pm
content: Good luck Legacy........