Re: How many floppies can I use with a Apple IIe

[Gregory Weston <uce@splook.com>]

In article <1191887565.668407.64900@y42g2000hsy.googlegroups.com>,
 Warren Ernst <wernst@gmail.com> wrote:

> On Oct 8, 4:19 pm, Rusty <rdek...@gmail.com> wrote:
> > On Oct 8, 6:54 pm, Linards Ticmanis <ticma...@gmx.de> wrote:
> > Other than needing a different controller, what are the differences
> > between the "smart" 800k drive and the "dumb" 800k drive. Is it that
> > the "smart" drive had more of the control electronics onboard so as to
> > need a less-sophisticated controller, or was it something else
> > entirely?
> >
> > Rusty D
> 
> The drive *mechanism* is identical. I've swapped drive mechanisms
> between Unidisk 3.5's and Apple 3.5's without problems. So that's not
> it.
> 
> The difference is in the electronics. The UniDisk has its own 6502
> processor and (I think) 2 kb of RAM to act as a buffer for the
> relatively slow and dumb //c (with newer ROMS) and //e (with Liron
> card) . The Apple 3.5 Drive has no smarts or buffer, and it is
> expected the host computer (A GS or early Macintosh) has enough speed
> and smarts to handle the data stream.

I never had an Apple 3.5 drive, but I did have 4 UniDisk 3.5 drives. 
There were two circuit boards inside, and if you removed the cable from 
the first and plugged it directly into the second (identical connectors) 
you got a functional "dumb" drive. The stock UniDisk 3.5 wouldn't work 
on a Mac, but the lobotomized version worked fine.