UsurpatorII emu questions

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Guenther
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UsurpatorII emu questions

Post by Guenther »

During research for something else I noticed that the emulation XB release of UsurpatorII by HGM completely escaped Leo and CCW and is currently
missing in the XB/UCI chronolgy, as it was released during my long break.

So far I know that it must have been released between end of 2007 and 02/2008. If HGM or anyone else has an exact date please tell here.

@HGM when was the last real work done for the emulated program itself,
or did you change/polish that too when releasing it?

currently the entry (not released) is filled with generic approximations:

Code: Select all

UsurpatorII			free	Emu	2008-01-01		-	1980-01	2008-01	37,57	9,57	D*	-	-	-	XB	Muller	Harm-Geert	http://home.hccnet.nl/h.g.muller/usurpatorIIemu.exe	NLD		
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hgm
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Re: UsurpatorII emu questions

Post by hgm »

I don't remember it. All computers I might hav used to put it together are long since dead. The file usurpatorIIemu.exe is from July 2011, but I think it is older than that. It should be possible to see when it first participated in the ChessWar promo division.

The program is exactly the same as what was published in the book; I actually recovered it from the book through OCR. What I then did is replace the calls to the routines that read or printed a move by stop instructions, and modified the 6502 emulator to recognize what these instructions should do by their location, and then do that task according to WinBoard protocol.
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Guenther
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Re: UsurpatorII emu questions

Post by Guenther »

hgm wrote:I don't remember it. All computers I might hav used to put it together are long since dead. The file usurpatorIIemu.exe is from July 2011, but I think it is older than that. It should be possible to see when it first participated in the ChessWar promo division.

The program is exactly the same as what was published in the book; I actually recovered it from the book through OCR. What I then did is replace the calls to the routines that read or printed a move by stop instructions, and modified the 6502 emulator to recognize what these instructions should do by their location, and then do that task according to WinBoard protocol.
It played in ChessWar in 02/2008 and you announced in 10/2007 it would probably be ready for this next ChesssWar ;-)
(Thus I assumed around 01/2008)

Can you extrapolate the date for the real UsurpatorII from the book release, or do you remember the date (YYYY is enough) you last worked on it?
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Re: UsurpatorII emu questions

Post by hgm »

This would be shortly before the book was published. It must have a date in it. But I am not at home now.
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Re: UsurpatorII emu questions

Post by karger »

The link actually works to download it , it is a very aggressive little engine and plays well under Shredder , Thanks Mr Muller
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Re: UsurpatorII emu questions

Post by Guenther »

hgm wrote:This would be shortly before the book was published. It must have a date in it. But I am not at home now.
Ok I found this old thread from 2011 in the WB Forum and here you said it is from 1979!
http://www.open-aurec.com/wbforum/viewt ... =2&t=51788

This post also contains info which I did not know about a possible commandline parameter - may be that info should be added to the according page at your site too?
Postby H.G.Muller » 22 Jul 2011, 17:37
...

I vaguely remember it needs a command-line argument, indicating the nominal depth in quarter plies. (It has no real time control; you have to set it to the approximate time per move you want it to play through this command-line parameter, and then hope for the best.) IIRC 12 is a good value for the TC used in the ChessWar promo. (Or was it 14? Perhaps Olivier still knows.)
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Re: UsurpatorII emu questions

Post by hgm »

The copyright notice in the book says (c)1983, so I guess that is the last year I worked on it. The leading comment block in the listing says (c)1980. The 1979 I mentioned in the posting is probably just a guess of the date I did started writing it, made from the top of my head.

To reconstruct the events: in the summer of 1977 I got my bachelor's degree chemisty, but because they had basically crammed all courses I had selected in the third trimester, I was one month later than others of by cohort, so that this technically counted as graduating in 77/78. I then received the 'Unilever prize' for best chemistry student at my university for that year, awarded in Q4 1978. As this was a cash prize, it enabled me to buy my own micro-computer (an AIM65). I must have obtained that early 1979. I almost immediately started working on writing a Chess program for that, as this was the major reason I wanted it.

Before that I had written a small Chess program 'Usurpator I' (in 2KB RAM) for a 6800-based home-build computer that I had borrowed for a few weeks. (Actually for fixing it, so that it would work.) The first version of Usurpator II was just a port of that program from 6800 to 6502 assembler. The comments were added only later, when I made the source into a stencilled booklet for handing out on a computer fair. The original AIM65 had only 4KB RAM, all needed to contain the machine code of the program and its data memory, and I had bought it with an 8K memory expansion to hold and edit the source code. (Saving things on non-volatile media in those days was a very slow and cumbersome task, involving audio-casette tapes.) I couldn't afford to waste any of that memory space on comments.

Anyway, I was constantly working on improving that program for the subsequent years, so the version that was in the 1983 book must have been from 1983.

I am not sure I have any info on Usurpator II on any of my web pages. I might have just uploaded the executable there for Olivier to download it.