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 gf (Get File) utility provides easy access to a built-in games repository. You can download classic retro games directly without needing to set up your own web server or navigate through GitHub repositories.

Using the Built-in Games Repository¶

The simplest way to download retro games is using the -g option:

From the Altair web terminal CP/M command prompt, use the Get File command with the game option:
```
gf -g love.bas
```
The game file will be downloaded directly to your CP/M filesystem.
Start the game from the CP/M command line:
```
mbasic love
```

Common Games Available¶

Here are some popular games you can download:

gf -g love.bas          # The classic Love game
gf -g menu.bas          # Menu system for games
gf -g adventure.bas     # Text adventure game
gf -g lunar.bas         # Lunar Lander simulation

Alternative: Manual Repository Access¶

You can also browse and download games manually from the Retro Games repository if you prefer to see what's available before downloading.

Important Note: Many retro games expect to find MENU.BAS in the CP/M filesystem. Be sure to download it as well:

gf -g menu.bas

Retro game acknowledgments¶

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