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galgame: MAME ROM Information.


Galaxy-Game [First Version] (c) 1971 Computer Recreations, Inc.

Welcome to Galaxy-Game. If you wish to play, simply rotate the power dial on the power timer behind the couch to the ON position. It will turn itself OFF.

Rules for playing are on the game themselves. Enjoy playing the first coin-operated video games created.


Galaxy-Games machines were installed in Stanford University's Tresidder Student Union in September 1971 and quickly became tremendously popular.

Galaxy-Game was the first coin-operated video games (with "Computer Space"). Using a DEC PDP-11/20 minicomputer, designers Bill and Hugh produced a reprogrammed version of the classic "SpaceWar!" game (as "Computer Space").

From 1972 to 1979, Tresidder had "Galaxy-Game [Second Version]" that could include up to 4 displays.


Re-programmed by : Bill Pitts, Hugh Tuck

Original concept by : Martin Graetz, Stephen Russell, Wayne Wiitanen


Machine's picture.

MAME Info:

0.144 [Quantum Leaper, Mariusz Wojcieszek, hap]


- 0.144: Quantum Leaper, Mariusz Wojcieszek and hap added Galaxy Game (Computer Recreations, Inc 1971).

- 5th November 2011: MAME - hap fixed listing errors (including ROL) pointed out by Quantum Leaper at MAMEWorld. Also went over the listing compared to the sw97 pdf and fixed some typos and alignments. This included a couple of typos in the data section, these are the correct ones as per sw97 pdf.

- 1st November 2011: Mariusz Wojcieszek - First of all thanks for your hard word on OCR-ing original PDF listing, it made Galaxy Game driver possible. T11 is good enough for the driver at this point, when PDP-11/20 is emulated (which may happen on MESS side), driver may be switched to use it. I'm loading code from compile code listing (taken from your site actually). I guess it is best option now, as it allows source code to be preserved, while still loading compiled code from it. About the bugs: I assume you are referring to these: "1006 006432 006601 10060 ROL R1" and "1007 006434 006602 10070 ROL R2". These are now patched during loading to use correct ROL opcodes. If there are more bugs in original listing which you fixed then, please let me know.

- 1st November 2011: MAME - hap added missing thrust button to Galaxy Game. Mariusz Wojcieszek fixed few errors in Galaxy Game listing - Game now playable.

- 31st October 2011: MAME - Mariusz Wojcieszek added Galaxy Game (marked as NOT_WORKING).

- 23rd February 2011: MESS - Miodrag Milanovic added skeletons for PDP-11 [Unibus](M9301-YA), PDP-11 [Unibus](M9312) and PDP-11 [Q-BUS] (M7195 - MXV11).

- 13th January 2011: Quantum Leaper - I was just wondering if the MAME team was going to do something with Galaxy Game. It been about 6 months since I finished recreating the source code and getting it to compile. I was just wondering should I have submitted something or what? I didn't want to bug the MAME Developers about it, since I know what can happen but from what I can tell it shouldn't be that hard of a game to add. Since the T11 chip has the Basic PDP-11 instruction set (except MARK) and MAME already emulates that chip. Ranger_lennier: Yes, I'm definitely glad for the efforts getting it typed and compiling. When I first got the source code I wasn't even sure it would be possible to make out everything. But emulating an actual PDP-11 would be the technically correct way, and as a bonus, MESS would get PDP-11 emulation. It might not hurt to ask on the MESS forum in case one of the MESS-focused developers is interested. But if no one wants to do it now, it may just have to wait. Or, if you're able to get anything running with it, even if it's not fully working, that would certainly be appreciated.

- 14th April 2010: Quantum Leaper - The PDF that the code if from has 12 errors but those are "Q" errors which are 'Questionable Syntax errors', and the code is from 2 working machines and the machines are currently at Computer History Museum in Mountain View, CA. So I know the code is clean and will compile and run. I just have to get out all the error from the code. I am hoping the hardware is pretty simple, so it can be emulated in full sometime in the future. I sure the MAME team would love to emulate the game, if I can get it compile and a runnable binary file. The real problem is MAME doesn't have a PDP11 emulated but they do have a T-11 (pdp11 on a chip) emulated. I know the opcodes from Galaxy Game are in the T-11, hopefully it won't be much work getting to run. Al Kossow: Bill was at the museum this afternoon so I talked to him for a while and got a few pictures of the insides. He didn't want to take the CPU apart, but he has another display board he'll bring over at some point. The 2903 display processor was a later design. The display in the game is very simple. It can do point plot characters and delta x delta y vectors. Pics at http://bitsavers.org/pdf/stanford/galaxyGame/photos/ .

- 13th April 2010: Quantum Leaper - I have the source code for an old PDP-11 game, called Galaxy Game it was at Stanford from 1972 to 1980. I got the source code from Bill Pitt though a third party, the problem was the code was in a PDF file. After OCRing and retyping the game, still checking the source code, I have a complete source code file. The problem is I don't know how to get it compiled and get a binary file that would be usable in an emulator. Any suggests on how to get it up and running, I will worry about a display later. Al Kossow: Use the assembler under a simulated RT-11 on SIMH. Could you post the version of the code that you've retyped? From conversations with Bill years ago, the display processor is a custom design they did. It probably implements a display list processor sort of like the DEC VT-11.

- 18th April 2006: Ranger_lennier - The first thing is new information on Galaxy Game. In 1971, Bill Pitts and Hugh Tuck founded Computer Recreations, Inc. and created Galaxy Game, a coin-operated videogame based upon Spacewar and running on the PDP-11/20 minicomputer. This makes it the first CPU-driven coin-op videogame. Some sources I've read say it was released even before Computer Space, generally considered to be the first arcade videogame (it didn't use a CPU). Does anyone know for sure? In 1972, they released an updated version allowing the computer to drive multiple displays. As obscure as this game is, it is an interesting part of arcade history, so I decided to try to track down more information on it. I struck gold when I discovered that Bill Pitts went on to found Incatech. I wrote him a letter addressed to his workplace expressing my interest in the game, including my hope that it could be emulated. It turns out he still had a printout of the source code to the 1972 version. "I still have a listing of Galaxy Game. I'm willing to give you a copy (PDF file) of it. You may do whatever you wish with it. If you actually begin the attempt to get it running, I'll explain the display processor interface". I got the code attached to the following e-mail. All files mentioned are linked for downloading: "Sw97.pdf (http://www.mameworld.info/ranger/sw97.pdf) is the source code that executed in Galaxy Game in the Coffee House at Stanford from early 1972 until 1980, which is when I removed the system because it was no longer reliable. Ignore all the pencil marks. The code as printed is what executed for 8 years. It is also the code that runs today in Galaxy Game at the Computer History Museum. This listing was produced by the Stanford Artificial Intelligence Project's PDP-10 system. Les Earnst, AI Project Director, was kind enough to look the other way while I borrowed some cycles. This code drove the two console system pictured in Jan72_0008.jpg (http://www.mameworld.info/ranger/Jan72_0008.jpg). There is an earlier version which was produced on the PDP-11 Paper Tape System. This version only ran for six months until it was replaced by the new two console system. Aug71_0005.jpg (http://www.mameworld.info/ranger/Aug71_0005.jpg) is a photo of the first system which was installed at Stanford in early September 1971. This system was the first coin operated video game". He also sent me a picture of the game in action, Aug71_0011.jpg (http://www.mameworld.info/ranger/Aug71_0011.jpg). The game looks much like Spacewar. I'd like to thank Bill Pitts for making all of this available. If anyone is familiar with the PDP-11/20, I would be interested in their analysis of the source code. I'm not familiar with the language (I'm assuming it's assembly), but there are some comments at least. Also, in a few places the printout seems a little difficult to read. Hopefully with everything in context it will be clear what each line is supposed to be. If you want to know more, try these links: http://www-db.stanford.edu/pub/voy/museum/galaxy.html (Stanford's Galaxy Game page).

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Romset: 125 kb / 1 files / 24.4 zip

MAME XML Output:

       <game name="galgame" sourcefile="galgame.c">
              <description>Galaxy Game</description>
              <manufacturer>Computer Recreations, Inc</manufacturer>
              <rom name="sw97.lst" size="127074" crc="838018a5" sha1="e3c47c5cf78299650b031ec49fde7d9e4024a759" region="code" offset="0"/>
              <chip type="cpu" tag="maincpu" name="T11" clock="3000000"/>
              <display tag="screen" type="raster" rotate="270" width="512" height="512" refresh="60.000000" />
              <sound channels="0"/>
              <input players="2" buttons="3" coins="4">
                     <control type="joy" ways="2"/>
              <dipswitch name="Players" tag="SR" mask="64">
                     <dipvalue name="Two Players" value="0" default="yes"/>
                     <dipvalue name="One Player" value="64"/>
              <dipswitch name="Speed" tag="SR" mask="128">
                     <dipvalue name="Slow Speed" value="0" default="yes"/>
                     <dipvalue name="Fast Speed" value="128"/>
              <dipswitch name="Sun" tag="SR" mask="16384">
                     <dipvalue name="Sun (&amp; Gravity)" value="0" default="yes"/>
                     <dipvalue name="No Sun (&amp; No Gravity)" value="16384"/>
              <dipswitch name="Gravity" tag="SR" mask="32768">
                     <dipvalue name="Positive Gravity" value="0" default="yes"/>
                     <dipvalue name="Negative Gravity" value="32768"/>
              <driver status="good" emulation="good" color="good" sound="good" graphic="good" savestate="unsupported" palettesize="2"/>

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