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50 Pin Floppy to 34 Pin Floppy Converter Board

hexsane

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Wasn't sure where to put this.

Anyone with PCB skills want to layout a converter board? I'm up for at least 3 of these. Would like:

Edge and IDC 50 pin to edge and IDC 34 pin. I can think of a few jumpers that may be required but otherwise it fairly straight forward.

If you feel overly ambitious you could add a 24 volt to 12 volt step down power converter :)

-Matt
 
you would need pin-outs for said connectors. does the connectors need to be male or female? what jumpers are required and where do they do/go? Is there any other hardware needed or is it like the 68<>50 pin scsi converters?
 
http://home.iae.nl/users/pb0aia/cm/8-525.html
http://nemesis.lonestar.org/computers/tandy/hardware/model16_6000/floppyfix.html

Jumperable: Motor on(16) to GND - 34 pin side. Ready(22) to GND - 50 pin side and 10 / 12 swap on the 34 pin side for using modern 1.44 drives to get DS0 and DS1.

EDIT: 2 side(10) to GND on 50 pin side.

You would have to adjust for the flip that is already in the a modern cable I think. When I make a cable I usually remove that flip and do my own 10 / 12 flip.

I'm building another cable (if I can find the connectors laying around here) today so I can fill in the gaps. (added 2 side line).

-Matt
 
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Anyone that has done the opposite (8 inch 50 pin drive to 34 pin controller connector) can chime in. I have not done a connect like this but being able to go either direction could be handy and I don't know if there would be differences in the required jumpering.

-Matt
 
I have a couple of the old Microsolutions 34-controller-to-50 drive boards; you can copy that if you'd like. OTOH, the FDADAP might be preferable as it also supplies TG43 signals.
 
I have a couple of the old Microsolutions 34-controller-to-50 drive boards; you can copy that if you'd like. OTOH, the FDADAP might be preferable as it also supplies TG43 signals.
Well, it's a bit confusing since Matt only says floppy-to-floppy and doesn't specify direction in the heading, but it sounds like he wants to go in the opposite direction, i.e. 50 pin controller to 34 pin drive; can the FDADAP board be used in both directions if you leave out the then irrelevant TG43 logic?
 
Well, it's a bit confusing since Matt only says floppy-to-floppy and doesn't specify direction in the heading, but it sounds like he wants to go in the opposite direction, i.e. 50 pin controller to 34 pin drive; can the FDADAP board be used in both directions if you leave out the then irrelevant TG43 logic?

Seems pretty obvious to me:

Matt said:
Anyone that has done the opposite (8 inch 50 pin drive to 34 pin controller connector) can chime in. I have not done a connect like this but being able to go either direction could be handy and I don't know if there would be differences in the required jumpering.

So he's going from a 34 pin controller to 50 pin drive or "50 pin drive to 34 pin controller".

The FDADAP might be reversible to connect a 34 pin drive to 50 pin controller. The MS adapters are certainly reversible, as they're nothing but PCBs. And even in the case of 8" drives, TG43 isn't required by all drives--some later ones have the smarts to count the cylinders themselves.
 
Seems pretty obvious to me:

So he's going from a 34 pin controller to 50 pin drive or "50 pin drive to 34 pin controller".
Umm, he said
Anyone that has done the *opposite* (8 inch 50 pin drive to 34 pin controller connector) can chime in.
... and it's probably related to replacing the missing 8" drive in his RS 12 with 3.5" drives...
 
I have and I'm chiming in.
LOL!

I still think he's going the opposite way to your
"he's going from a 34 pin controller to 50 pin drive or "50 pin drive to 34 pin controller".
but I guess it doesn't really matter aside from the different cables he'd need; I wonder though whether the extra cost of the FDADAP that you were recommending would be worth it if you're just going to use it in reverse.
 
I'm finding myself frequently cobbling together 8" controller to 5.25" (or 3.5") drive cables. It would be nice to order a board instead of a bunch of IDC connectors and save the time. I also went thrift hunting for floppy cables and ended up buying a few from a guy on craigslist as none could be found.

The idea is if a board can be routed then it'll be available for those lacking the skill / tools to make a cable. It would be nice if it were dual purpose and able to connect an 8" drive to a PC for those wanting to read / write real 8" disks.

-Matt
 
Should be pretty easy, particularly if all you need is two male headers on the board. Most of the pins are in roughly the same order for drive types. A simple double-sided PCB would do.

Remember that PC drives use the second drive select on a drive; that's not usually the case with systems that use 8" drives.
 
Which one is the second drive select? I am considering ordering a batch of boards. I have already started drawing schematics actually. But I want to make it more like FDADAP with more indicators than just track number.
 
Which one is the second drive select? I am considering ordering a batch of boards. I have already started drawing schematics actually. But I want to make it more like FDADAP with more indicators than just track number.

Have you seen NF6X's adapter? I've used them successfully a number of times for adding 5.25 drives to 8 in machines. Maybe you can enhance it with a track indicator.

https://github.com/NF6X/fd50to34
 
Thanks, I have not seen this one. I want to enhance the plain passive adapter with TR43 signal and some LEDs for INDEX, WP, DCR and probably connector for 1602 LCD module, which are ridiculously cheap nowadays.

Was "Write Failed" signal ever used on American drives? It was used on some east-Europe-block drives when write was attempted on write protected diskette. It had to be reset by the controller.
 
If you're going 8" Controller -> 5.25" drive, you shouldn't need to generate TG43. LEDs are easy to add, but if you're wanting an LCD for some purposes, that kind of implies there will be a microcontroller on board -- something to keep in mind if you've never done development for microcontrollers (not that it's super difficult to get started, especially nowadays, but it's another step).

Between NF6X's board and the FDADAP you're probably covered on functionality. I personally use the FDADAP, I haven't had a need to connect 5.25" drives to an 8" controller as of yet, but I'd probably order NF6X's board if I needed to, rather than make up a cable.
 
It should be bi directional. TG43 will therefor have jumper to be disconnected for 8" Controller situation. I am thinking about AT89C2(4)051, ASM code and 4bit LCD1602 HD44780 because it needs less pins then 2 digits of 7 segment LED displays and can show much more information. That way I could show track number for drives A and B simultaneously, rpm of drives and so on. Such LCD costs 2$ delivered on ebay.

Few LEDs for instant diagnosis would be fine too. Only thing that bugs me is LED for INDEX, it will probably need 74123 prolongator to be visible. I will first experiment with LEDs on universal board for a while.
 
Are pin limits still a big issue in the Atmel world? I pretty much buy PICs based on I/O requirements; for example, my 24-bit hex display uses a PIC16F6310 because it has 50-some I/O pins and costs very little in single quantities.
 
I have tested the LEDs. I made jumpers for Motor On, Drive Select to be able to start the drive. Soldered LEDs to Write Protect, Track 0, INDEX with 74HCT123. It works as expected.

And btw I believe I have found out why one of my recently acquired TEAC FD-55GFR 193U's can not read floppies written on other HD drives. It could read floppies that it itself wrote. My guess was bad Track 0 sensor or misaligned tracks. To my surprise I spotted only by looking now to flashing LED on INDEX pin that it flashes slower than the working drive(s). Another Mitsumi 509 flashed also faster. This non working TEAC spins probably at 300rpm.

I will work on the adapter.
 
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