Consolidated patched Source code, Unix build scripts & Binaries for CP/M 3

This repository collects the necessary files to build the distribution files for CP/M 3 (aka CP/M-Plus) under Linux/Unix/macOS.

These are based on the Open Source release of Digital Research files courtesy of DRDOS Inc. (owner of the rights to the software) and the prior work of John Elliott who incorporated patches and developed the build procedures - see https://www.seasip.info/Cpm/software/dri.html

Previously, the license terms restricted distribution from the "Unofficial CP/M Web Site" at http://www.cpm.z80.de/ - but this no longer applies. The revised licensing is here .

I have maintained my own copy of these files and incorporated the missing build procedure for the Intel PLI-80 source file for the INITDIR.COM program, plus added the random read fix to the BDOS ported from ZPM3.

The Makefile has been written for GNU Make.

I have included the PL/M development system and Intel PL/I-80 V1.4 compiler from the Unofficial CP/M Website http://www.cpm.z80.de/binary.html

You will need:

• The ZXCC emulator (version 0.3 or later) installed. Grab the updated version based on John Elliott's ZXCC v0.5.7 from https://github.com/agn453/ZXCC

• The Thames ISIS emulator for Unix (version 0.1.0 or later) installed http://www.seasip.info/Unix/Thames/ (I've included thames-0.1.1.tar.gz)

The PL/M system contains the PLM80 compiler, the ASM80 assembler, and the ISIS emulator. These have already been unpacked to separate directories plm80, asm80 and utils.

The Intel PL/I-80 V1.4 directory pli80-v1.4 contains the CP/M binary PLI.COM and overlays PLI?.OVL that you should copy to the ZXCC BINDIR80 directory (by default this is /usr/local/lib/cpm/bin80) and the PL/I library PLILIB.IRL to the ZXCC LIBDIR80 (into /usr/local/lib/cpm/lib80). These should have lowercase filenames so that ZXCC can find them.

The following steps will set a build in motion -

cd $HOME/src	# or where you keep your download source files
git clone https://github.com/agn453/cpm3.git
cd cpm3/cpm3src_unix
## If you haven't already copied PL/I-80 for ZXCC to use
# cp pli80-v1.4/pli.com pli80-v1.4/pli[0-2].ovl $BINDIR80/
# cp pli80-v1.4/plilib.irl $LIBDIR80/
make all

Since the build tools do not return error codes, you will have to watch for error messages yourself, and stop the build if you see one.

When either gencom.com or minhlp.com are being run, you may see a "corrupt FCB" message. This is caused by them closing a file they didn't open, and you may safely ignore these messages.

The build date is stored in five files:

mcd80a.asm
mcd80d.asm
mcd8f.asm
makedate.lib
show.plm

and you should change all of these if you are making a new release.

Pre-built binaries are in the cpm3src_unix/cpm-dist/ folder.

--

Tony Nicholson, Sunday 22-Jun-2025