It controls it in the same way PC controller does, the trick is in grabbing raw data instead of relying on primitive hardwired decoders in descendants of uPD765.

>hard it is to build something that reads the magnetic signal, or what's left of it, directly from the floppy platter

Thats exactly what floppy drive does :)

> Thats exactly what floppy drive does :)

I meant as a viable home project, doesn't have to be a fully functional drive as long as it somehow allows to view the magnetic values, manually turn their 2D structure into the valid 1.44MB filesystem if necessary :)

Floppy drive does not decode disk data on its own, it merely amplifies analog signal from magnetic head, filters and quantizes it (zero crossing).

https://patents.google.com/patent/US4656533A/en

What you get on a READ pin of floppy drive is the same information you would probing read head (or rather preamp) using Oscilloscope. All you are interested in is magnetic field flipping, zero crossing, encoded on READ pin as an impulse.

Sure, you could precision machine turntable like contraption to do it manually, but floppy drives are plentiful and practically free.

Yes. You could make your own magnetics value reader which would also be a functional drive but perhaps not 'fully' in that it might be slow etc. For example you could make a high resolution x,y table with a read head that made a flux map and the you could post process this into the data. Using an existing floppy drive seems so much more practical for the job of data recovery.

Take a look at the kryoflux, https://www.kryoflux.com/

Doesn't Kryoflux still require an actual floppy drive to be connected? I think the parent poster was looking for a way to do this without using an actual full floppy drive

Do you really think the article is about someone connecting a logic analyzer directly to a floppy sitting on the lab bench? No, he's connecting it to a floppy drive. That's only logical and also described in the article that you didn't read. Also mentioned in the article in the first paragraph is Kyroflux... Most people only read the headline before commenting?

Thanks, I read the article and I understand all of this. I was just explaining how a kryoflux would not be appropriate for reading a floppy drive "sitting on a lab bench", which I assume is the question that the grand-parent comment was asking.

Which is not an unreasonable question to ask. People have done similar things with vinyl records - reconstructing the audio from a photograph/scan of the record with no "vinyl drive". https://mediapreservation.wordpress.com/2012/06/20/extractin...

Without floppy drive you would have to build a..floppy drive, kind of redundant.