image of READY prompt

Here is an assortment of technical files: schematics, timing information, manuals, and any other low-level information that can be gathered or reverse engineered. While this page has some links to key documents, explore the links to learn more about a few in-depth topics.

The documents page contains all of these manuals and more, but this section presents just the ones that provide substantial implementation details.

Here are a collection of architecture and maintenance manuals for various 2200 Systems. These are all available in the docs page, but are collected here for convience.

The Model 2200 Systems Maintenance Manual provided about 90% of the information I needed to write my Wang emulator. A big thanks to Jan van de Veen for having the manual, Georg Schäfer for making a copy, and Fritz Chwolka for scanning it. Not only does it describe the CPU structure, it contains information about a few subsystems as well.

Alternately, you may want to read the VP architecture and instruction set manual (87 pages, 3 MB) written by Paul Szudzik when he was at Computer Concepts Corporation. This was the result of reverse engineering the 2200 system in order to develop add on products.

The technical manual for the Wang 7180 disk controller (79 pages, 879 KB) was useful in reverse engineering the disk channel protocol in order to add disk support to the Wang 2200 emulator. Later on, Mike Bahia donated Microprocessor Manual of Mass Storage Devices (155 pages, 8.1 MB) which is the previous document obviously was extracted from. Because the disk channel implemented a protocol (as opposed to a direct low level control interface), the disk drive needed intelligence to perform its end of the handshake. Wang did this with simple microcoded CPUs; ironically, the disk controller here had an 8b CPU while the 2200 CPU was only 4b. The Disk Channel Description page has a summary and interpretation of the data found in the manual.

This document contains a few very interesting documents detailing some of the implementation details of BASIC-2.

I had a system with a MVP backplane, but a flaky CPU board set. I also had a spare microVP card. After studying the backplane connections, I came up with a small backplane wiring change which allows using the microVP and CS/386 CPU cards in the modified MVP backplane.

While working on the emulator, I had the need to understand what the 8080 processor was doing on the 2236 MXD terminal mux card. This listing is the result of a few weeks of free time to reconstruct source code. This zip file contains the source .asm file, the above listing file, and intel .hex and raw .bin versions as well.

The assembled output exactly matches that of the original ROM, but there very likely are misleading/confused comments as there are still a few sections which I didn't spend enough time to figure out. In its current state it was enough for my purposes. Let me know if you find any errors.

William and Patricia Payne wrote a book in 1982 called Implementing BASICs: How BASICs Work (3 MB, 224 pages). Despite the generality of the title, it is mostly about Wang 2200 MVP BASIC. This gives some insight into what is going on under the hood of the BASIC interpreter, such as how the variable table is organized, and how the interpreter analyses the source for errors and how it carries out execution of a program.

If you have any technical documents on the Wang 2200 or its peripherals, I'd certainly like to hear about it.