Altair 8800 Simulator

The Altair 8800 simulator is part of the SIMH family of simulators. It has the following features:

  • Choice of processor (8080 CPU, Z80 CPU or 8086 CPU)

  • Optional banked memory (16 banks with 64 Kbyte)

  • MMU supporting ROM and memory mapped I/O

  • Optional hard drive support for additional storage capacity

  • Networking support via TCP/IP for client/server systems

  • Support for multiple consoles

  • Timer and keyboard generated interrupts

  • Various devices for Northstar, Vector Graphic and CompuPro

  • Ability to set the clock speed for “real-time” simulation (useful for games)

The Altair 8800 simulator is able to run CP/M 2.2 (along with a variety of other operating systems), which makes it a perfect companion for the HUNTER. Using CP/M 2.2, running on the Altair 8800 simulator, you will be able to configure CP/M software ready for use on the HUNTER (see Configuring Typical CP/M Programs) or compile CP/M programs written in a variety of programming languages.


The Altair 8800 simulator may be downloaded from Versions are available for IBM-PC, Mac OS X (Intel), Linux (Intel) and the Sharp Zaurus.

Files created using the Altair 8800 simulator may be transferred to the HUNTER using the HUNTER File Transfer Utility.

Import/export files into/from the simulator

On the CP/M 2.2 disk you find the programs R.COM and W.COM. With the CP/M command R XYZ.COM you can transfer the file XYZ.COM from your local directory into the simulator environment. The command W XYZ.TXT does the opposite, i.e. the text file XYZ.TXT is transferred from the CP/M disk to your local directory. W XYZ.COM B transfers the file XYZ.COM in binary mode.

In case you need to transfer multiple files you can use wildcard characters or alternatively you can create a batch file containing the necessary commands. Execute the batch file using DO.COM (this is the same program as SUBMIT.COM).

VT100 Emulation

Some CP/M applications such as WordMaster (WM.COM) require a terminal with cursor addressing capabilities. The VT100 terminal is a typical example and most CP/M programs with nontrivial console output have been customized for the VT100.

The recommended way for using the VT100 capabilities is as follows:

  1. Boot CP/M (or any other operating system) as usual.

  2. Type ^E (Control E) to stop the simulator.

  3. Type ATTACH SIO 23 and confirm with the return key. Port 23 is the default port for Telnet sessions and you need to make sure you have the necessary permissions to create a socket on this port. If not, you must run the simulator as “root” or with the sudo command or use another port.

  4. Type GO and confirm with the return key.

  5. Start Telnet or PuTTY (Windows).

  6. Connect Telnet (or PuTTY) to and make sure you specify the port you chose in section 3 if you are using a port different from port 23.

Now you can execute all commands in the Telnet (or PuTTY) terminal window which supports VT100 emulation.

CP/M Software

The Altair 8800 simulator website contains a variety of CP/M software, including Programming Languages, Office Applications and Games.