Creating new CP/M disk from scratch
Roy J. Tellason
rtellason at blazenet.net
Fri Jun 2 20:37:41 CDT 2006
On Friday 02 June 2006 09:14 pm, Bill Sudbrink wrote:
> Roy J. Tellason wrote:
> > On Friday 02 June 2006 08:44 pm, Richard A. Cini wrote:
> > > I'm having trouble locating someone (anyone) who has
> > > a bootable 5.25" single-density diskette suitable for
> > > my VersaFloppy controller. So, I was wondering the
> > > following. What if I setup an old PC with a 5.25" drive
> > > and use 22DISK to prepare a disk and move CP/M 2.2
> > > .COM files to it from the PeeCee. Then, I would have to
> > > figure out how to get the cold-start loader onto the disk.
> > Writing the system tracks is definitely going to be the hard
> > part, all right. Because you need that to include a BIOS
> > that's specific to your hardware. I'm in the same spot with
> > regard to my BigBoard II, which I can boot a Xerox SSSD
> > floppy on but then I only get SSSD support, even though the
> > hardware and the drives support DSDD.
> > If you figure out how to do this I'd sure like to hear about it.
> You might try using Dave Dunfield's ImageDisk program. Fill the
> whole image with hex E5 except for a small "hello world" type
> program in the boot sector and see if it runs. Once you get that
> working, then put your real boot loader, CBIOS and CP/M in the
> appropriate sectors on the first couple of tracks. You should
> then be able to boot to an empty disk. Do some SAVEs to create
> some files in the file system and then copy the disk back to the
> PC using ImageDisk. Fill in the sectors of the SAVEd files with
> real data in the disk image and write another disk.
The problem is, I don't _have_ an appropriate CBIOS for the BBII. Maybe I
oughta take another look, see what's out there on the 'net, as it's been a
while. I paid way too much for that machine when I bought it (as a kit) and
figured I'd defer the costs of the software until later on. Unfortunately
the software only came on 8" floppies, and it was quite some time after that
I actually acquired any, and I knew of very few people that had 'em. But
anyhow when the time finally arrived that I realized that I really should
have those sources it was too late, the company had gone out of business. I
did talk at some point around there to Jim Ferguson, who designed that
board, and he referred me to the guy who did the software (whose name
escapes me at the moment), and although I attempted to get in touch with him
I never did hear back from him.
There's some really nifty stuff in the rom, like the board looking at both
serial ports and the built-in stuff to determine where you are talking to it
from, adjusting the baud rate automatically in the case of a serial port or
the strobe polarity in the case of an ascii keyboard, and when I had the
thing in a box with drives hooked up I could tell it to read a sector and
it'd do so, doesn't matter what sector size or what density, I could even
stick a DOS floppy in there and keep hitting the 'r' key until you'd start
seeing directory entries in the DUMP-type display...
I have that board sitting in a box here, and really oughta get it out and
play with it some, and I probably will, once I unclutter this room some.
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
Information is more dangerous than cannon to a society ruled by lies. --James
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