Can I use external floppy drive as internal drive?
 

I have an A1200 in the loft with a bust floppy drive, I tried replacing it with the drive out of a bust A500 which worked except it physically won't fit in the case :/

Found an old slimline external drive a while back, wondered if these were pin compatible on the inside. I took it apart just now, there are a couple of small chips on an interface board, I looked them up, a couple of flip flops and some Nand gates, presumably this just handles the drive select logic. So if I can get the drive out of the chassis can I connect this directly to the Amiga as DF0? Or do those chips do something else special?

I would mod the A1200 case to allow the drive's own bezel to poke out.

Yes, the drive mechanism should be compatible with the internal drive port. :)

The logic on the interface board is for latching the drive select signal and passing the correct drive select signal to the next drive in the chain, if it has a pass through connector.

hmm, good news! I'll have to get that A1200 out of the loft again now then, I can use it for more experimental stuff.

I've had an idea since, I wonder if it's possible to use an Arduino to interface directly with a floppy drive's motors and read/write head to get it to read Amiga disks. I have found people's projects where they are controlling the stepper motor and/or spin motor, and others where they are using the head to store and play back audio data, so it must be possible. "New" Amiga floppy drives? Worth a shot.

Indeed, and a very interesting project it would make too! :)

So what do you intend to do with the Amiga data once you have read it with the Arduino? It is definitely possible to do, as the drive just outputs a bit stream for you to decode once you've turned the motor on.

Kryoflux already exists, and it was not a trivial effort, but I'm sure the project would be very educational if you intend to recreate that functionality in your own design / code.

And now I don't understand. What is the Arduino's role in making new Amiga floppy drives? All you need is to get the diskchange and ready signals to the correct pins and your PC mechanism is Amiga compatible. No micro controller needed.

Or were you going to make another floppy emulator akin to the HxC or MegaDrive256? I'd recommend looking at something more powerful than an Arduino in that case, mainly so that your device would be faster and more convenient to use. I'm thinking minimum delay in mounting the images/converting adfs to raw data..

I gathered only some models of PC disk drives could be modified in this way, and that they were getting increasingly hard to find. Especially difficult is finding one that can read HD disks on Amiga.

Yeh, the HD part is the holy grail really. Hard to do without extensive drive modifications.