Re: apple2 hardware interfacing.

[dempson@actrix.gen.nz (David Empson)]

Supertimer <supertimer@aol.com> wrote:

> "Klil N." <spamfree@poboxes.com> wrote:
> 
> >Hello,
> >I have both a specific question and a general one:
> >*Specific: Is it possible to take a standard 3.55' IBM-PC
> >floppy drive and connect it to a slot on an enhanced (65C02)
> >Apple2e-and have it work? Will Apple DOS recognise it or do
> >I have to get ProDOS?
> 
> SHH Systeme makes a controller, the BlueDisk, that does
> this already.  You can run ProDOS off it, but it won't read
> DD disks from regular Apple drives.  It will read HD disks from
> a SuperDrive.  Check Nathan's FAQ or the FAQs on Ground
> for information on contacting SHH Systeme.
> 
> There is a program that lets PC drives connected in this
> way read MS-DOS disks.

You didn't answer the question about whether Apple DOS 3.3 would
recognise the drive.

I don't know the answer to this, but at the very least, it would require
a patch to DOS 3.3 (which only supports Apple or compatible 5.25" drives
as standard).  In addition, DOS 3.3 is limited to 400K per volume (50
tracks, 32 sectors per track, 256 bytes per sector), and some
applications don't like anything except 140K volumes.

There have been patches to DOS 3.3 which allow it to use 800K 3.5" disks
(as two logical 400K volumes), so a similar patch would be possible to
use a 720K MFM 3.5" disk with a BlueDisk card.  1.44MB would require at
least four logical volumes to enable access to the entire disk, and this
is likely to run into yet more compatibility problems with applications.

In short, it would be an awful lot easier to stick with ProDOS.

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand