Sargon (chess)
Encyclopedia
Chess
Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...
-playing software for personal computers.
Origin
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Zilog Z80
The Zilog Z80 is an 8-bit microprocessor designed by Zilog and sold from July 1976 onwards. It was widely used both in desktop and embedded computer designs as well as for military purposes...
-based computer called Wavemate Jupiter III
using assembly language
Assembly language
An assembly language is a low-level programming language for computers, microprocessors, microcontrollers, and other programmable devices. It implements a symbolic representation of the machine codes and other constants needed to program a given CPU architecture...
through TDL Macro Assembler.
The name was originally written entirely in capitals because early computer operating systems such as CP/M
CP/M
CP/M was a mass-market operating system created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc...
did not support lower-case file names.
Introduction
SARGON was introduced at the 1978 West Coast Computer FaireWest Coast Computer Faire
The West Coast Computer Faire was an annual computer industry conference and exposition most often associated with San Francisco, its first and most frequent venue. The first fair was held in 1977 and was organized by Jim Warren and Bob Reiling. At the time it was the biggest computer show in the...
, where it won the first computer chess
Computer chess
Computer chess is computer architecture encompassing hardware and software capable of playing chess autonomously without human guidance. Computer chess acts as solo entertainment , as aids to chess analysis, for computer chess competitions, and as research to provide insights into human...
tournament held strictly for microcomputer
Microcomputer
A microcomputer is a computer with a microprocessor as its central processing unit. They are physically small compared to mainframe and minicomputers...
s. This success encouraged the authors to seek financial income by selling the program directly to customers. Since magnetic media were not widely available at the time, the authors placed an advert in Byte Magazine and mailed photocopied listings that would work in any Z80-based microcomputer
Microcomputer
A microcomputer is a computer with a microprocessor as its central processing unit. They are physically small compared to mainframe and minicomputers...
. Later they were contacted by Hayden Books
Hayden Books
Hayden Books was a publisher of computing books, and published several titles written by Larry Pina....
and a book was published.
Commercialization through electronic media
When magnetic media publishing became widely available, a Navy Petty Officer, Paul Lohnes, ported Sargon to the TRS-80TRS-80
TRS-80 was Tandy Corporation's desktop microcomputer model line, sold through Tandy's Radio Shack stores in the late 1970s and early 1980s. The first units, ordered unseen, were delivered in November 1977, and rolled out to the stores the third week of December. The line won popularity with...
, altering both graphics, input, and housekeeping routines leaving the Spracklen's chess-playing algorithm intact. Paul consulted with the Spracklens, both living in San Diego at the time, to make the TRS-80 an instant success with the help of Hayden Book's newly established software division: Hayden Software. Paul was not involved in further refinements to the TRS-80 version due to his reassignment to sea duty shortly after signing the deal with Hayden Software.
In the first eighties SARGON CHESS was ported to several earlier microcomputers, i.e. NASCOM
Nascom
The Nascom 1 and 2 were single-board computer kits issued in 1977 and 1979, respectively, based on the Zilog Z80 and including a keyboard and video interface, a serial port that could be used to store data on a tape cassette using the Kansas City standard, and two 8-bit parallel ports...
(by Bits & PCs, 1981), Exidy Sorcerer
Exidy Sorcerer
The Sorcerer was one of the early home computer systems, released in 1978 by the videogame company, Exidy. It was comparatively advanced when released, especially when compared to the contemporary more commercially-orientated Commodore PET and TRS-80, but due to a number of problems including a...
, Sharp MZ 80K
Sharp MZ
The Sharp MZ is a series of personal computers sold in Japan and Europe by Sharp beginning in 1978.-Overview:...
, and many others.
A complete rewrite
Rewrite (programming)
A rewrite in computer programming is the act or result of re-implementing a large portion of existing functionality without re-use of its source code. When the rewrite is not using existing code at all, it is common to speak of a rewrite from scratch...
was necessary later for the Apple II
Apple II
The Apple II is an 8-bit home computer, one of the first highly successful mass-produced microcomputer products, designed primarily by Steve Wozniak, manufactured by Apple Computer and introduced in 1977...
port, made by Kathleen's brother Gary Shannon. Both were published by Hayden Software.
Sequels
The Spracklens made some significant improvements on the original program and released Sargon II. This version was ported to a variety of personal computers popular in the early 1980s. The game engine featured multiple levels of lookaheadLookahead
Lookahead is a tool in algorithms for looking ahead a few more input items before making a cost effective decision at one stage of the algorithm.- Lookahead in search problems :...
to make it more accessible to beginning chess players. Even though chess programs of the time could not defeat a chess master
Chess master
A chess master is a chess player of such skill that he/she can usually beat chess experts, who themselves typically prevail against most amateurs. Among chess players, the term is often abbreviated to master, the meaning being clear from context....
, they were more than a match for most amateur players.
Sargon III was a complete rewrite from scratch. Instead of an exchange
Exchange (chess)
In the tactics and strategy in the board game of chess, an exchange or trade of chess pieces is series of closely related moves, typically sequential, in which the two players capture each others pieces. Any types of pieces except the kings may possibly be exchanged, i. e. captured in an...
evaluator, this version used a capture search algorithm
Algorithm
In mathematics and computer science, an algorithm is an effective method expressed as a finite list of well-defined instructions for calculating a function. Algorithms are used for calculation, data processing, and automated reasoning...
. Also included was a chess opening
Chess opening
A chess opening is the group of initial moves of a chess game. Recognized sequences of opening moves are referred to as openings as initiated by White or defenses, as created in reply by Black. There are many dozens of different openings, and hundreds of named variants. The Oxford Companion to...
repertoire. This third version was written originally for the 6502
MOS Technology 6502
The MOS Technology 6502 is an 8-bit microprocessor that was designed by Chuck Peddle and Bill Mensch for MOS Technology in 1975. When it was introduced, it was the least expensive full-featured microprocessor on the market by a considerable margin, costing less than one-sixth the price of...
assembler and was commercially published by Hayden Software in 1983. Some years later the couple was contacted by Apple and after a port for 68000
Motorola 68000
The Motorola 68000 is a 16/32-bit CISC microprocessor core designed and marketed by Freescale Semiconductor...
assembly
Assembly language
An assembly language is a low-level programming language for computers, microprocessors, microcontrollers, and other programmable devices. It implements a symbolic representation of the machine codes and other constants needed to program a given CPU architecture...
, Sargon III was the first third-party executable software for the Macintosh
Macintosh
The Macintosh , or Mac, is a series of several lines of personal computers designed, developed, and marketed by Apple Inc. The first Macintosh was introduced by Apple's then-chairman Steve Jobs on January 24, 1984; it was the first commercially successful personal computer to feature a mouse and a...
.
After the demise of Hayden Software, later chess programs were also released under the name Sargon, including Sargon IV (Spinnaker Software
Spinnaker Software
Spinnaker Software was a 1982 founded software company known primarily for its line of non-curriculum based educational software, which was a major seller during the 1980s. It was founded by chairman Bill Bowman and president C. David Seuss....
), Sargon V (Activision
Activision
Activision is an American publisher, majority owned by French conglomerate Vivendi SA. Its current CEO is Robert Kotick. It was founded on October 1, 1979 and was the world's first independent developer and distributor of video games for gaming consoles...
) and a CD-i
CD-i
CD-i, or Compact Disc Interactive, is the name of an interactive multimedia CD player developed and marketed by Royal Philips Electronics N.V. CD-i also refers to the multimedia Compact Disc standard used by the CD-i console, also known as Green Book, which was developed by Philips and Sony...
title simply named Sargon Chess.
The Spracklens also ported Sargon 2.5 to a dedicated unit, Applied Concepts' Modular Game System. The Spracklens concurrently wrote the engines for the dedicated chess computers produced by Fidelity Electronics, which won the first four World Microcomputer Chess Championships.
The Botvinnik game
The famous three-time world chess champion Mikhail BotvinnikMikhail Botvinnik
Mikhail Moiseyevich Botvinnik, Ph.D. was a Soviet and Russian International Grandmaster and three-time World Chess Champion. Working as an electrical engineer and computer scientist at the same time, he was one of the very few famous chess players who achieved distinction in another career while...
played a game with Sargon in 1983 at Hamburg. He did not play his best moves and only tested the program's capabilities. Botvinnik himself was also involved in chess program development.
White: Mikhail Botvinnik
Black: SARGON
Hamburg, 1983
1.c4 e5 2.Nc3 d6 3.g3 Be6 4.Bg2 Nc6 5.d3 Nf6 6.f4 Be7 7.Nf3 O-O 8.O-O Qd7 9.e4 Bg4 10.h3 Bxh3 11.f5 Bxg2 12.Kxg2 Nb4 13.a3 Na6 14.b4 c5 15.b5 Nc7 16.Rh1 a6 17.b6 Nce8 18.Ng5 Qc6 19.Rb1 Bd8 20.Nd5 h6 21.Nf3 Nxd5 22.exd5 Qd7 23.g4 a5 24.Nd2 Ra6 25.Ne4 Rxb6 26.Rxb6 Bxb6 27.f6 Nxf6 28.Nxf6+ gxf6 29.Bxh6 Re8 30.Qf3 Bd8 31.Qh3 Qa4 32.Bd2 Kf8 33.Rf1 Kg8 34.Qh6 Qd7 35.Kg3 f5 36.Rh1 f4+ 37.Kf3 1-0