Make sure you have sufficient free space (for example NOS 1 you will need at least 100 MB). The emulator will create a large number of files in your work directory. Depending on your emulated disk configuration you may need several GB of disk space on your host system.

For best performance I recommend that your video card and monitor support a resolution of 1200 x 1024. I also suggest a host system with at least 500 MHz CPU and with 128 MB of RAM or more.

Please note that the configuration file “cyber.ini” controls many aspects of the operation of the emulator. Please study this file carefully. It controls the equipment configuation and deadstart panel as well as other system parameters. You can activate the main configuration sections (for example “smm” and “cos”) by renaming either it “cyber” or specifying the section name on the command line.

To exit the emulation at any time, hit ALT-O on the console to enter the operator interface and then type “shutdown” in the text window.

The emulator should be executed within its own work directory. When started from a text window it will print a few startup messages and then launch a graphical console window. The graphical console window is used to emulate a Cyber console. The text window from which the emulator was started, will be used to output critical status messages and also to provide an operator interface (by typing ALT-O in the graphical console window).

Desktop Cyber’s console window is a 6612 display console emulator. Since the 6612 didn’t have a full keyboard, not all keys are supported. If you try to enter a key which isn’t supported, the emulator just ignores it. Most keys map obviously. Although the 0 on the 6612 was to the left of the 1, Desktop Cyber uses the 0 right where it’s found on the conventional keyboard.

The CR key maps to ENTER.

The only non-obvious mapping (for those who have not used a 6612 console) is for the two keys present on the 6612 but not seen on conventional keyboards—the left and right blank keys. The left blank maps to [ and the right blank to ].

On a 6612, the left and right blank keys are on either side of the = key, as shown in figure 2-1 below. To a 6612 operator, pressing [ and ] for the left and right blank keys “feels” right.
The left blank clears the text you have entered on the command line (as a control-U in many UNIX shells). Except at dead start, in DIS, and O26, the right blank doesn’t do anything. See the NOS Version 1 Systems Programmer’s ?>Instant, pub. 60449200, for details on DIS and O26 usage.

The console subsystem's keyboard behaves similar to the real thing except for the following differences:

• Right blank key is mapped to “]”
• Left blank key is mapped to “[”
• ALT-O enters the operator interface (use it to shut down, mount tapes and remove paper)
• ALT-0 to ALT-9 toggle instruction tracing for PPU 0 to PPU 9
• ALT-C toggles instruction tracing for the CPU
• ALT-E toggles tracing for Exchange Jumps

By default, Desktop Cyber’s console emulator isn’t pedantic about key rollover—on a true 6612 console, the operator couldn’t type very fast; the console would only accept one key at a time, so the operator had to develop a somewhat awkward punch-and-wait keyboarding technique when sitting at the console. You don’t have to worry about that— just type as you normally would. (If you are accustomed to the true rollover behavior, you may set this option in the Desktop Cyber Operator Interface.

Please note that instruction tracing is intended for debugging and generates very large files very quickly! I recommend you only trace around interesting sections. When you activate tracing, the execution speed also dramatically drops.

Additional debug support is provided in the form of in-core disassembly of PPU memory, PPU dumps and CPU dumps. These debugging features are enabled by conditional compilation in the source file “main.c”.

Please not that a large number of files created in the directory where the emulator executes are for debug support and may contain instruction traces, dumps and disassemblies. These files will normally be empty unless tracing, dumping or disassembly is enabled.

Apart from the very early Chippewa OS all later CDC Operating Systems are copyrighted by CDC's successor Syntegra. They are now available for hobbyist use.