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DoctorWkt / pdp7-unix

A project to resurrect Unix on the PDP-7 from a scan of the original assembly code
GNU General Public License v3.0
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PDP-9 Spacewar #209

Open larsbrinkhoff opened 4 years ago

larsbrinkhoff commented 4 years ago

There was a version of Spacewar for the PDP-9 with Graphic-II display. I believe the Bell Labs people said they had a version of Spacewar, so maybe it was that one?

I have two files: source code, and an assember listing. I can't share them now, but they will go public.

larsbrinkhoff commented 4 years ago

The question is, would this program be appropriate for this project? We can speculate that this is indeed the Spacewar that was running on the Unix PDP-7. After all, how many Graphic-II Spacewar versions could there be?

sebras commented 4 years ago

I found an old alt.folklore.computers usenet posting that mentions Spacewar for PDP-9 and has a partial source code listing. I don't see any GRAPHIC-2 instructions there, but there might be in the other parts.

larsbrinkhoff commented 4 years ago

https://www.bell-labs.com/usr/dmr/www/spacetravel.html says:

Later we fixed Space Travel so it would run under (PDP-7) Unix instead of standalone, and did also a very faithful copy of the Spacewar game originally done (I think) at MIT on the PDP-1, but that was a different game.

The copy I have runs standalone, and it's written in MACRO-9. So I guess there were (at least) two different Graphic-II Spacewar versions.

larsbrinkhoff commented 4 years ago

I started this Spacewar on SIMH. It wasn't an immediate success, because the G-2 instruction words didn't make much sense. The display list is generated dynamically, so some debugging will be needed.

Possibly my translation from listing to binary was bad, or else this software is using some other version of the G-2 hardware.

larsbrinkhoff commented 1 year ago

Here is the code:

https://github.com/chriswalker-ge635/PDP9-SPACEWAR