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Learn about CP/M

CP/M originally stood for Control Program/Monitor. Later, CP/M became known as Control Program for Microcomputers. It was a mass-market operating system created in 1974 for Intel 8080/85-based microcomputers by Gary Kildall of Digital Research, Inc.

The first version was single-tasking on 8-bit processors with support for up to 64 kilobytes of memory. Later versions of CP/M added multiple-user variations and were migrated to 16-bit processors.

For more information about CP/M, see the CP/M Wikipedia article and CP/M Frequently Asked Questions.

Digital Research CP/M Operating System Manual​

You will find a wealth of information about CP/M, including compilers, assemblers, debuggers, and more in the Digital Research CP/M Operating System Manual

Programming the Altair emulator​

From CP/M, you can program the Altair emulator using Microsoft BASIC, BD Software C, the Intel Assembler and Linker, and the Microsoft MACRO-80 Assembler.

Get started with CP/M​

Here are some CP/M commands to get you started:

  • Changing drives. The Altair emulator mounts two drives, drive A and drive B. To change drives, from the Altair CP/M command prompt in the Web Terminal, type the drive name, then press the Enter key.

    a:

    b:

  • Display a directory listing.

    dir

    dir *.BAS

    ls

  • Erase a file.

    era *.txt

  • Copy Microsoft BASIC mbasic.com from drive A to drive B.

    a:pip b:mbasic.com.com=a:mbasic.com

  • List the contents of a file.

    type hw.c

  • Rename a file.

    ren hello.c=hw.c

Get started with retro gaming​

Download a retro game​

The following is an example of copying the love.bas game to the CP/M filesystem using the CP/M gf command.

  1. Review the Retro Games repo.

  2. From the Altair web terminal CP/M command prompt, run the Get File command:

    gf

  3. Select endpoint 1 (GitHub)

  4. Type the name of the file to be transferred. For example LOVE.BAS. Note, that the filenames are case sensitive.

  5. Press Enter to start the transfer.

  6. From the CP/M command line, start the game. For example

    mbasic love

Note, a lot of the retro games in the repo expect to find MENU.BAS in the CP/M filesystem. So be sure to transfer MENU.BAS as well.

Retro game acknowledgments​

This list of games was made possible by the dedicated work of CP/M Games and Vintage BASIC.