Reading various format 5.25" floppies on a PC

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Sun Jun 15 20:50:01 2003

> I've got disks for the following machines which I'd like to initially back up:
>
> Acorn BBC / BBC Master / Cambridge Workstation (I believe these are all the
> same low-level format even if filesystem structure is different)

Original BBC micros used a 8271 disk controller chip which is
single-density (FM) only. Many PC disk controllers can't handle that.
Later, Acorn used the 1770 (which can do double desinty (MFM) _as well_),
but still used single density recording as the standard.

> DEC Rainbow (B model, if there's a difference between that and the A)

That one is possible, there are shareware MS-DOS programs for this
(probably different for Rainbow CP/M and MS-DOS disks). The Rainbow disks
(RX50 drive) are are 80 cylinder single sided, so you need a 1.2M drive.

>
> Apple (Apple ][, //e and /// - again I believe low-level structure is the
> same for all 3?)

Apple used GCR encoding on these machines, which can't be handled by
_any_ standard PC disk controller.

-tony
Received on Sun Jun 15 2003 - 20:50:01 BST