ontrca wrote on 2023-05-10, 01:46:

eesz34 wrote on 2023-05-09, 16:29:

Also, have you taken the top cover off to see if there's anything non-standard in there?

I took the cover off.

Looks very normal. Does it perform a seek at boot, provided that's enabled in BIOS? Older BIOSes did not have the ability to turn it off.

Provided it does, another thing to try is format a disk with it. Let's say the alignment is way off. You could likely still format a disk. At least you'd know that much.

eesz34 wrote on 2023-05-10, 02:18:

ontrca wrote on 2023-05-10, 01:46:

eesz34 wrote on 2023-05-09, 16:29:

Also, have you taken the top cover off to see if there's anything non-standard in there?

I took the cover off.

Looks very normal. Does it perform a seek at boot, provided that's enabled in BIOS? Older BIOSes did not have the ability to turn it off.

Provided it does, another thing to try is format a disk with it. Let's say the alignment is way off. You could likely still format a disk. At least you'd know that much.

Enabled in BIOS.
But it doesn't do anything at boot.

Thank You to everyone (:

I think I'm going to give up..... ? ....

I tried to look up the MPF-420 (I replaced the C with a 0 on purpose) and even though that FDD seems contemporary (same mounting hole spaces, PCB same shape, but different layout), it's still quite different.
I'm somewhat surprised these drives came with no documentation.
You could try a manual of a Sony drive of about the same era and see if it has similar jumper settings.

What year is your drive made? There should be a date code on the PCB somewhere.

ontrca wrote on 2023-05-10, 06:26:

Thank You to everyone (:

I think I'm going to give up..... ? ....

I'd be so curious and try controlling this manually. Only jumpers to ground or another pin is required. Although, if you've already connected a known good drive to the same cable, seems that should do the same thing.

And feedback on eBay say nothing about this other than "great transaction blah blah". So weird.

eesz34 wrote on 2023-05-10, 11:28:

And feedback on eBay say nothing about this other than "great transaction blah blah". So weird.

And 60 units were sold. I assume those buyers know how to make it works

sangokushi wrote on 2023-05-10, 18:27:

eesz34 wrote on 2023-05-10, 11:28:

And feedback on eBay say nothing about this other than "great transaction blah blah". So weird.

And 60 units were sold. I assume those buyers know how to make it works

I would encourage the buyer to message the seller and ask about this. I've bought items from that buyer before and in my experience they are pretty good.

MPF 42A seems to be for an old Apple Mac, there is also a MPF 42B not sure what it is intended for., but maybe the whole MPF 42 series are for Mac? (Ok, this was disproved below)
There was this Superdrive thingy that could read different odd formats for the older Macs, which might need some special speed control hardware for the motors.

The four jumpers marked M0,M1,M2 ,DI could be the stepper motor control (M0-2: track resolution)...maybe DI jumper is also interesting to try out Drive 0/1 select or Drive Initiate at power on?

There were some SCSI floppies, but those would need a CPU controller, rather than an FPGA.

Another possibility would be drives for one of the Amigas perhaps? Not sure what they needed.

Maybe something for a professional syntheziser/sequencer? Some had floppies.

Medical instruments, also several test&measurement instruments for electronics industry.

(Sony had a camera with a floppy, but that came out later this this drive.)

Rwolf wrote on 2023-05-11, 17:27:

MPF 42A seems to be for an old Apple Mac, there is also a MPF 42B not sure what it is intended for., but maybe the whole MPF 42 […]
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MPF 42A seems to be for an old Apple Mac, there is also a MPF 42B not sure what it is intended for., but maybe the whole MPF 42 series are for Mac?
There was this Superdrive thingy that could read different odd formats for the older Macs, which might need some special speed control haardware for the motors.

The four jumpers marked M0,M1,M2 ,DI could be the stepper motor control (M0-2: track resolution)...maybe DI jumper is also interesting to try out Drive 0/1 select or Drive Initiate at opwer on?

There were some SCSI floppies, but those would need a CPU controller, rather than an FPGA.

Another possibility would be drives for one of the Amigas perhaps? Not sure what they needed.

According to this post, MPF-42B is intended for some floppy disk duplicators:
https://forum.vcfed.org/index.php?threads/iso … -drive.1241616/

Rwolf wrote on 2023-05-11, 17:27:

but maybe the whole MPF 42 series are for Mac?

I doubt this is the case.

From what I remember, floppy drives of the early to mid 90s tended to have model numbers that were the same for any particular generation, but the letters and numbers after that would indicate a sub-variant and these sub-variants could be drives made for a whole range of different purposes (usually for different types of computers (like for instance IBM which often used non-pc compatible FDDs) or different machines altogether (like maybe specialist musical instruments or some kind of industrial machines or for some kind of external enclosure perhaps)). The older 3.5in FDDs often had a lot of jumpers, making it more configurable in some ways. In some cases the jumpers were probably there to improve backward compatibility or something.
Different sub-variants could be for different jumper layouts even. And I'm fairly sure not all FDDs are gonna be PC compatible, or at least not without some form of modification.

I do want to point out I'm not a specialist in this regard, there is a huuuuge amount of different 3.5in FDDs made, especially in the earlier years and I don't know what all these different models made them different from the next model.
Later 3.5in FDDs tended to be made more uniformly, lacking many of the features (and also apparent robustness) the older FDDs had because it was cheaper that way.

The early years of the 3.5in FDDs are somewhat more misty and I think a lot of knowledge and knowhow was lost because not a lot of people cared about 3.5in floppy drives for a long while. So finding info on any very specific drive may prove a challenge unless some kind of hoard of old (probably scanned) manuals is found 😋