Software: MESS PDP1

spacewarSome time around 1998 I tried to involve myself in the mess emulation project. Apart from Move I implemented the first functioning PDP1 emulation to the mess core.

Again – I don’t know how much is left of my doings from nearly 20 years ago. Here are the original sources I contributed: mess.pdp1.rar

The original readme I wrote for the contribution:

Driver for a PDP1 emulator.

Preliminary, this is a conversion of a JAVA emulator.
I have tried contacting the author, but heard as yet nothing of him,
so I don't know if it all right with him, but after all -> he did
release the source, so hopefully everything will be fine (no his
name is not Marat).

Note: naturally I have no PDP1, I have never seen one, nor have I any
programs for it.

The only program I found (in binary form) is


The first Videogame EVER!

When I saw the java emulator, running that game I was quite intrigued to
include a driver for MESS.
I think the historical value of SPACEWAR! is enormous.

SPACEWAR! is public domain, so I include it with the driver.
So far only emulated is stuff needed to run SPACEWAR!

Not even the keyboard is fully emulated.
For more documentation look at the source for the driver,
and the pdp1/pdp1.c file (information about the whereabouts of information
and the java source).

In SPACEWAR!, meaning of the sense switches

Sense switch 1 On = low momentum            Off = high momentum (guess)
Sense switch 2 On = low gravity             Off = high gravity
Sense switch 3            something with torpedos?
Sense switch 4 On = background stars off    Off = background stars on
Sense switch 5 On = star kills              Off = star teleports
Sense switch 6 On = big star                Off = no big star

LISP interpreter is coming...
Sometime I'll implement typewriter and/or puncher...
Keys are allready in the machine...

Bug fixes...

Some fixes, but I can't get to grips with the LISP... something is
very wrong somewhere...

(to load LISP for now rename it to SPACEWAR.BIN,
though output is not done, and input via keyboard produces an
'error' of some kind (massive indirection))

Added Debugging and Disassembler...

Another PDP1 emulator (or simulator)
is at:

including source code.
Sometime I'll rip some devices of that one and include them in this emulation.

Is a packet which includes the original LISP as source and
binary form plus a makro assembler for PDP1 programs.

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