Hoofless Horseman

So this is the Panasonic PRONOTE PD CF-62, it's a Pentium 133mhz running Windows 95, released in August 1996. Panasonic did this sort of trick more than once, they did a similar thing with an under-keyboard CD-ROM drive in the PD CF-41, from 1995.

This one is so fancy because that's not just a self-loading under-keyboard laptop CD-ROM drive, it's a HYBRID PD/CD-ROM self-loading under-keyboard laptop drive! It has to be this complex because it takes PD discs (which are the size of caddies) and caddyless CD-ROMs!

So what's PD discs?

They're an optical format by Panasonic, the Phase-change Dual (or Phase-change Disc). They're from 1996, store as much as CD, but are rewritable... much like the later CD-RWs which used basically the same technology, just in a slightly different format. Unlike CD-RWs (which you had to burn (usually), they acted like a hard drive, fully rewritable at any point. That's why the disc is hard-sectored, which you can see through the shutter gap. Those vertical lines indicate where sectors start and end.

So yeah, this laptop has a complex drive that can take both types of discs, and the whole thing folds under the keyboard. Fucking wild.

But the root reason, of course, is that they did this because it's a cool design, and they wanted to do that. Why did they think this was cool, why did they want to do this?

Pervert reasons.

short answer:

probably C:, if not D:, but could be anything up to Z:

long answer:

It depends entirely on which version of DOS this machine uses.

Originally DOS assigned all floppy drives first, then hard drives, then network drives. So a system with three floppy drives and one hard drive would get floppy drives A:, B:, C:, hard drive D:

DOS 5.0 (from 1991) changed it, and it now does the first two floppy drives, then the primary partition of hard drives, then all the extra partitions of hard drives, THEN floppy drives from 3 and up.

So a single hard drive machine (assuming it's not partitioned into multiple drives) with three floppy drives, will have floppy drives A:, B:, and D:, with hard drive C:.

historical answer:

It originally worked this way because DOS copied how CP/M did it, and CP/M just assigned the letters A-Z to all drives, without treating hard drives specially (especially because you probably didn't have a hard drive back then)

actual answer:

The floppy drive is A:. This machine only has one floppy drive.

This case has blanking plates for the 3.5" floppy drive bays that look like fake 3.5" floppy drives. I don't know why it does this, it's very weird and confusing, and in this picture they've installed neither of the possible 3.5" floppy drives, so both of those are fake, and only the 5.25" drive is real.

mythbusters recreate-the-myth answer:

I went into 86box and set up an IBM XT with three floppy drives, and installed DOS 3.3 and then DOS 5.0 on it:

Here in DOS 3.3, you can see that our floppy drives got numbered A:, B:, and C:, and the hard drive is D:

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