Anders Hesselbom

CP/M on a Commodore machine – online resources

2011-05-29

To get started with CP/M, you will need a Commodore 128 with a disk drive or a computer that runs Vice (X128). The disks you need can be downloaded from here. The CP/M boot disk, the additional utilities, “more CP/M additional utilities”, the Assembler utilities and Microsoft Basic 80 (two disks).

If you run this on a physical machine, make sure to insert the boot disk, and to push in the “40/80 display” key on your computer, before turning it on. If you are running this from Vice emulator, start your machine by passing these arguments to the x128 executable (adjust the path if necessary):

x128.exe -80 -autostart "C:\cpm\zpmsys.d64"

This is a text only environment, but pseudo graphics can be used, and a graphics library is available as an add-on.

The basic usage of CP/M is described in the Commodore 128 user guide, chapter 11. If you know DOS, you will probably feel rather at home. You have the concepts of programs and arguments. DIR shows the available commands. The actual Commodore extensions consist of keyboard short cuts and are described in chapter 15 of the Commodore 128 user guide.

What I see as the biggest challenge, is inserting the correct disk. Let’s say that you want to read the content of a file. This requires the TYPE.COM file that is located on the additional utilities disk, so you must insert that disk to be able to run that command. To avoid frustration, use two disk drives – one for the CP/M disks, and one for your files.

To start Microsoft Basic, insert the correct disk and type MBASIC. Then, watch a movie or something. After a while, your Commodore 128 will say:

MBASIC-80 Rev. 5.21
[CP/M Version]
Copyright 1977-1981 (C) by Microsoft
Created: 28-Jul-81
34350 Bytes free
Ok

If you want to write programs, the MBASIC manual can be downloaded from here.

A five minute Turbo Pascal 3.0 demo on the Commodore 128:

Categories: Geeky

Tags: C128