On Tue, Jul 27, 2004 at 10:46:49PM -0500, Doc Shipley wrote:
> Bottom line requirement is that I be able to low-level format an 8"
> floppy to RX02 format. IIRC, RT-11 can flip the switch from RX01 to
> RX02 in an RX02 drive, right?
Yes. So can OS/8. The "flip" is when an RX02 drive re-writes part of
the sector to double density. That's what makes them so hard to read
on non-DEC hardware - the media becomes both single and double density.
Both RX01 and RX02 disks start off with "Industry Standard" IBM-compatible
low-level formatting, AFAIK. There are third-party DEC-compatible drives
that can take an absolutely blank disk and lay down tracks. I would think
a suitable CP/M system could do the same. Post-1982 hardware is where
things start to get tricky.
> And I need to be able to accurately copy a bootable RX02 diskette to
> a formatted blank.
In terms of development and set-up time, I would think a PDP-11 would
be the fastest way to just dup floppies.
> I'd *like* to be able to take a disk image of a floppy as a file, and
> to write that back out to floppy, but that's gravy.
That's trivial with a VAX (BACKUP/PHYSICAL). There must be a way with
smaller hardware (2BSD on a PDP-11, perhaps?)
I wonder what it would take to hook a real RX02 up to modern hardware. The
interface isn't complicated, but AFAIK, it would take more than a PeeCee
parallel port to drive it. Similar to hooking up a real Commodore 1541
to a modern machine and siphoning off a physical backup...
-ethan
--
Ethan Dicks, A-130-S Current South Pole Weather at 28-Jul-2004 03:50 Z
South Pole Station
PSC 468 Box 400 Temp -100. F (-73.5 C) Windchill -126.1 F (-87.90 C)
APO AP 96598 Wind 3.7 kts Grid 114 Barometer 673.8 mb (10860. ft)
Ethan.Dicks_at_amanda.spole.gov http://penguincentral.com/penguincentral.html
Received on Tue Jul 27 2004 - 23:07:54 BST