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IBM 4869 External 360KB floppy drive rewired to work on IBM 5150/5160

VERAULT

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I am just curious if anyone has gotten an External IBM 4869 (which is wired up to work on microchannel IBM ps2 drives) connector rewired/pinned to work on the external connector on the FDC of an IBM 5160/5150. The internal drive is a bog standard 360K drive and will work if directly connected; the only difference is the pinout of the connector. Just curious if anyone has done this to make the drive more functional to older pc's.


ibm4869.png
 
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I would hazard that yes, someone has but that 36 pin connector is a pretty massive hurdle. It's a molded plug so you can't just open and repin it. You'd need to make some sort of an adapter that sits between the card header and the drive's plug. I thought about the same thing when I discovered the external Apple PC 5.25" drive was doing the same thing, but was also stealing +5 and +12 from the mac.
 
I would hazard that yes, someone has but that 36 pin connector is a pretty massive hurdle. It's a molded plug so you can't just open and repin it. You'd need to make some sort of an adapter that sits between the card header and the drive's plug. I thought about the same thing when I discovered the external Apple PC 5.25" drive was doing the same thing, but was also stealing +5 and +12 from the mac.
Was it molded? Oh you mean the external connector! Right! I was actually thinking about re-pinning the INTERNAL connector.

If it was plausible I suppose the best thing would be to compile a pinout for every line and post here to ensure something like that wouldnt happen.

A start would be to do a list of its current setup.
 
I've done it frequently (still have a few new 4869 boxes). I posted a blog here years ago on the how-to. Maybe someone can dredge it and the images up. Or, like things Internet, I was fooling myself in thinking that my posting might be for posterity and not scribbled in sand.
Before the changes to the forum were made, did anyone bother to back the old one up, complete with images and attachments? Didn't think so...
 
Thanks Chuck, Noone needs to reinvent the wheel if you have a 14 and a half year old post already covering it!
 
I also have such a drive and I would need an adapter to go on a standard 34 pin controller. I want to run it with a 4 drives adapter on a Adaptec 1542a/b controller as the 3rd drive. How to wire this? The 4 drive adapter is quite simple, so I have already two 34 pin connectors on the floppy controller, the 2nd connector is connected separately to DS3/4 and motor 3/4 of the controller chip while all other signals are parallel to the 1st connector.

As most PC bios do only support 2 floppy drive, I need to have a driver, which one?
 
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That looks good. I now need to get the DSUB-37 connector, might be difficult today.

By the way, do you also know the pinout of the DSUB-25 connector of SYSGEN drives? I also have such one.
 
So I just made the change following Chucks instructions. I have to say its alot harder than it looks. Particularly opening and taking about the IDC connection. Its different from all the standard dual inline pin variety I am used to using. The outer retainer tap (with the metal clips) must have somehow broken off when I was opening it up so I had to use a little glue to hold it in place after it was completed. As soon as it dries I plan on testing it on my IBM 5155.
 
Did not work for me. I am trying to troubleshoot the cable. Is there a pinout of this I can follow? As what I am seeing is not making sense.
 
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