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Any projects to interface a 5.25" drive as a USB device?

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bitfixer

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I was curious if there were any projects around to directly interface a 5.25" floppy drive, hd or otherwise, as a modern USB storage device?
I imagine you could do this either by using a FDD ISA controller card, and then interfacing with that, or by talking directly to the floppy itself.
This is mostly for amusement as it would be kind of fun to use a 5.25" floppy on my modern machines. Has anyone worked on or heard of such a project? Thanks.
 
I guess this could also be useful for making floppies from image files without need for a bridge machine. Assuming the implementation of the interface allowed for that.
 
If you are implying you want something that can let you open My Computer and just click on the 5.25" floppy icon like you would with any other drive, no that does not exist. Believe me I've been checking on this for several years now. It isn't that Windows 10 cannot support 5.25" floppy drives (yes the driver and support is STILL there). There is just nothing beyond a traditional floppy controller either onboard or in PCI/ISA format has been created which will hook into Windows the same way. All modern USB floppy adapters either assume 3.5" is the only thing that exists or it's the even more enhanced multiformat adapters like the Fluxengine or Kryoflux which bikeshed the idea of *only* existing to allow hardware support for 5.25" floppy drives and *only* the two classic PC formats under Windows.

It's logically baffling.....

If you dig far enough into the forum I asked the same question and got pointed at the FluxEngine. For as nice as it was compared to the KryoFlux or other floppy adapters it's painfully incomplete in terms of format support.
 
I too have been looking for something like this for at least 10 years now. The ideal solution would allow for 4 disk drives connected at once: 360KB, 720KB, 1.2MB, and 1.44MB. Genuinely surprised that at the very least a 5.25" to USB adapter has not been made for mass production in all these years.
 
There was one, 20 years ago. With slight tweaks to the drivers, the SMSC USB floppy controller should have been able to handle all the standard PC formats and drives plus the possibility of floppy tape. The SMSC combined a 8051 with standard floppy controller and shows up as a standard USB floppy. The 3 mode driver for 3.5" drives should have been simple to adapt to the 1.2MB 5.25" floppy drive. 360K and single sided modes aren't baked in so might have taken a bit more work but it should have been possible to extend to a lot of 8", 3.25", 3", 2.5" and 2" formats. Unfortunately, getting the chips and driver source code is quite difficult now.
 
Does anyone have the SMSC driver source?
I was going to use a black pill and a NS floppy controller. Bought the parts and have been off doing other projects I could finish faster

the part was the usb97cfdc2-01, EOL August 1, 2008
 
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You could always take a standard legacy FDC, add some RAM and couple it to a modern MCU. Pretty much the same as a Micro Solutions Backpack floppy, but with USB instead of parallel I/O. But at least that didn't limit you to a small selection of formats.

I'm not a big fan of USB floppies because they actually limit one to a very narrow range of formats.
 
Also found this, but it is read only:
http://deviceside.com/fc5025.html

Seems like an interesting project to undertake. I think using a legacy fdd controller and interfacing to that seems like a good idea - else you would have to re implement a lot of low level drive control stuff.
I almost wonder if using some kind of embedded full DOS machine with a built-in controller might be a possibility, since then you could interface with USB at a higher level, allowing DOS to directly interact with the floppies. Almost cheating though, as then you essentially do have a bridge machine you're using.
 
I suppose you could implement it as a bulk-transfer device, but the standard way of doing a mass-storage device (MSD) involves implementing the full range of SCSI commands and encapsulating them in the USB interface. Check out some of the libraries for MCUs for examples; e.g., this one from libopencm3. It's an insane level of abstraction for what amounts to a simple memory device.
 
krebizfan said:
There was one, 20 years ago. With slight tweaks to the drivers, the SMSC USB floppy controller should have been able to handle all the standard PC formats and drives plus the possibility of floppy tape. The SMSC combined a 8051 with standard floppy controller and shows up as a standard USB floppy. The 3 mode driver for 3.5" drives should have been simple to adapt to the 1.2MB 5.25" floppy drive. 360K and single sided modes aren't baked in so might have taken a bit more work but it should have been possible to extend to a lot of 8", 3.25", 3", 2.5" and 2" formats. Unfortunately, getting the chips and driver source code is quite difficult now.
Click to expand...

https://www.rocelec.com/part/SMCUSB97CFDC-MN?utm_medium=buyNow&utm_source=findChips


These folks apparently have 14k of em in stock....
 
Interesting! Unfortunately a minimum order of 61, which is an odd number. Maybe we can find 60 interested people to split the order with.
 
bitfixer said:
Interesting! Unfortunately a minimum order of 61, which is an odd number. Maybe we can find 60 interested people to split the order with.
Click to expand...

uninteresting unless you can find the firmware development kit
you also need to say how much they want for them
as Chuck pointed out, it is non-trivial to get a mass storage stack put together, and you have to deal with programming an 8051
 
Would it be possible to take either a Super Card Pro or kryoflux card and read the diskette into a program that allows managing files, add, copy delete. Maybe even drag and drop. Have a virtual floppy similar to how windows handles writing CD's or DVD's, you write or burn the virtual floppy back to the diskette.

I know the Super Card Pro has a software development kit and the current software is written in VB6. If you used the Super Card Pro, I think is the developer is Jim Drew, he may be willing to lend some expertise. I have not looked at the kryoflux site to see if they offer software development assistance. I believe DosBox source is downloadable, it has routines to read and write floppy images. Would those routines at least be a starting point.

These are just questions, I certainly do not have the knowledge or expertise to develop the software. Some of the really knowledge people like Chuck or Al may point our how this is not possible or would be very difficult.
 
Jimmy said:
Would it be possible to take either a Super Card Pro or kryoflux card and read the diskette into a program that allows managing files, add, copy delete. Maybe even drag and drop. Have a virtual floppy similar to how windows handles writing CD's or DVD's, you write or burn the virtual floppy back to the diskette.
Click to expand...
If you are happy with this type of workflow:
1) read a floppy into an image file
2) modify the image file (use a program that allows you to list, copy in or out files, etc)
3) write the modified image file back to a floppy

the tools already exists today, for lots of floppy formats. No drag and drop, sorry. Tools like Greaseweazle and FluxEngine can do the reading and writing, tools like mtools (MS-DOS) and cpmtools (CP/M) can read and modify the images.
 
Jimmy said:
Would it be possible to take either a Super Card Pro or kryoflux card and read the diskette into a program
Click to expand...

You do realize that flux imagers don't do read retries, making them inferior to anything Imagedisk can read, since they aren't doing bitstream
decode on the fly?

It obviously could be fixed if the authors would realize what they are producing is GIGO
 
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