Has anyone here ever designed their own floppy disk controller in the spirit of Steve Wozniak? Meaning, have you ever just taken the drive mechanics and designed a controller for the drive?

When I study how the Apple II Disk was created and study how more advanced drives like the 1541 were designed, I can't help but feel drawn into trying my hand at something similar. Not that I actually would any time soon...too many other projects.

But it sure would seem like a lot of fun.

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Cat; the other white meat.

Now there's a project idea!

If you're going to do that, don't forget to kick it up a notch and go with a multi-speed drive ala the Apple Macintosh.

I seem to remember reading somewhere that Woz had a difficult time getting his design completed, because every time he fell asleep he woke up almost back at square one. He finally managed to stay up long enough to finish, then likely collapsed from exhaustion. I am orders of magnitude less talented than Woz, so it would be an absolutely hopeless endeavor for me, even if I wanted to do something similar.

Mike B.

(Woz relates the story in this 1984 interview published in BYTE magazine:




There's more interesting reading at woz.org and folklore.org

)

If I recall correctly wasn't woz using bare (and faulty) shugart mechanisms with no drive electronics?

It might be easier to work with pc floppy drives? I'd be interested in such a project to the nuts and bolts of how it works but I'm not anywhere near smart enough to do it myself

One thing that has worked wonders for me when working on complex stuff is modern version control - when I get back (the next day, or the next week, or the next year), I do a 'git log' and can see my earlier thinking laid out sequentially. That gets my mind on track again and I can continue where I left off.
Otherwise it would be a lot like going back to squre one every time..

Here's a PC style floppy controller someone built using an FPGA: http://www.craigsarea.com/vhdl_disk.html
Not only is there the code listing but also his university project explaining everything

On a recent search around the web, I found some info around an upgraded floppy controller that Atari did, based on the WD1772. As the older WD1772 only supports slower data rates (1MB 3.5-inch drive, aka 720KB formatted), Atari was initially hand-selecting specific chips to run their double density drives (2MB 3.5-inch drive, aka 1.44MB). As this was a longer term problem, they actually designed a upgrade replacement controller that handles the higher data rates. Here's a link with more detail:

http://www.best-electronics-ca.com/custom-i.htm#Ajax

I decided to pick up a few chips for future project use, a bit pricey at $29.95 however, but they appear to have ample stock for the time being. For anyone opting to build a (somewhat classic) floppy controller with a minimal parts count, these are a pretty good option.

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Regards, KM
https://github.com/floobydust

Thirty bucks each? Ouch!

What about a data sheet?

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

True, on the pricey side... as for a datasheet, shouldn't need one. It's just a WD1772 that will handle a 16MHz clock input and support double the date rate and storage capacity with the later 2MB diskette drives. All commands, status, etc. are the same.

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Regards, KM
https://github.com/floobydust

I picked up a 1773 today relatively cheap, $6 aud https://www.ebay.com/itm/WDC-WD1773-PH- ... SwT2daJ6Z~

Remains to be seen if it’s real.

:edit: for some reason I thought this one would support HD data rates. No idea what I was thinking :/
Guess I don’t need 1.44MB anyway