[sebhc] CPM

Dwight K. Elvey dwight.elvey at amd.com
Tue Jul 6 12:35:34 CDT 2004

 Last week I got an image file for CP/M to run on hard sectored
disk. It had SuperCalc on it so I needed to do a little post
processing because I don't want to have any copyright issues
on our group. Maybe someone can find the owners of this program
to get permission to post it as well.
 There are a couple of people in the group that have full release
issues of CP/M2.2 but I thought I'd get things started. I've
created an image with the SuperCalc deleted so that we can
get started.
 Once the disk had SuperCalc deleted, there was only STAT and PIP
left. I wanted to include some more stuff so I decided to write
a program that would transfer a CP/M files that I had on my
PC to the image file. These files and more can be found on the web.
It was to be a simple project. It ended up taking most of my weekend.
 To write the code, only took me about 3 to 4 hours. I then
started to debug and realized that there were a number of things
I didn't fully understand about the CP/M directory structure.
Rather than ripping up my code and starting again, I did
a bunch of patching ( usually a bad idea but one thinks it
will just take a couple of patches ). After some time ( about
twice as long as writing the code ) I finally got everything
working( Why are we such slow learners? ).
 I wanted to make the code so that anyone could use it and
release it to the group. Up till then, I'd been just running
it in FPC ( a public domain Forth ). I needed to convert it
to a more useable format for all. I used a program called
TCOM that creates small *.COM files for DOS. TCOM is mostly
OK with Forth source that works under FPC ( written by the
same fellow ) but has limitation on the relative sizes of
the code within control structures ( like if else then ).
This required some factoring of the code ( always a good
idea anyway ). Of course, I broke the code a couple times
in the process and had to debug that.
 I finally got things to work. I had the files for a few
useful CP/M utilities so I created a disk image with these
on it. I had ASM, DDT, ED, LOAD and DUMP added to the disk
with the original PIP and STAT. Things like FORMAT will
have to wait until we get a release image since it is machine
dependent code.
 I have sent the code in for the ftp and it should be available
later on the FTP.
 To run this CP/M, you need a machine with 64K of zero
based RAM , XCON8 ( the Z80 board or a modified 8080 system )
and a 5-1/4 hard sectored disk system. You can used my H89LDR
utility to transfer the image to the H8/89 or similar. MAKE
DISK!!!! These are not HDOS disk and there is no volume
number information in the images for my transfer program to
look for.
 I have include the following:

 CPMWR.COM     a DOS file to copy CP/M compatible files to
                a CP/M disk image file ( assuming that there is
                space on the disk for the file ).
 CPMWR.SEQ     Source for CPMWR for your enjoyment.
 CPM22.IMG     Bootable CP/M image with PIP and STAT only.
                My *.IMG are the same as *.H8D format.
 CPM22P.IMG    Same as above but with ASM, DDT, ED, LOAD
                and DUMP added
 CPMWR.TXT     A read me file. Please actually read.
 I've sent these as CPMWR.ZIP so I'm not sure if they'll split
these out for the FTP or not. It has both a utility file and
image files. This should get those that have been
waiting for some CP/M to play with a chance to get started.
We still need things like FORMAT, SYSGEN, CONFIGUR and DISKCOPY.
Right now, the only way to make new formatted disk is to
use my transfer program ( not exactly a friendly method ).
 If someone puts to gether some include files for the ASM
with system specific info, let the entire group get copies.

Delivered by the SEBHC Mailing List

More information about the Sebhc mailing list