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Home * Engines * Sargon

Sargon I for the Apple II [1]

a family of chess programs by Dan and Kathe Spracklen. They started chess programming in 1977 on a Z-80 based Wavemate Jupiter III [2] in assembly language. The first Sargon version had a 10x12 board board representation and a two ply alpha-beta search without quiescence but a SOMA like exchange evaluation [3] [4].

After first tournament successes in 1978, at The Second West Coast Computer Faire, winning with a 100% score [5], and the shared third place at ACM 1978 already with Sargon II, the Spracklens became professional computer chess programmers. They first started selling their well commented Sargon I Z-80 assembly listing as paper copy for $15 by their own [6], and then made a contract with Hayden Books to publish a book about Sargon with explanations and listing [7]. Hayden Software [8] remained primary distributor of all further Sargon software versions, even when the Spracklens worked full time for Fidelity Electronics during the 80s.

MOS Technology

Sargon I was already ported to the Apple II by Kathe Spracklen's brother, Gary Shannon [9]. Despite its lower frequency, they found the 6502 the much better processor for their program than the Z80, and soon the MOS Technology processor became the major target platform.

Sargon II

Sargon II was written for various Z-80 and 6502 based home computers, and was base for their first dedicated unit, the Chafitz ARB Sargon 2.5 [10]. After civil proceedings between manufacturer Applied Concepts [11] and their sales company Chafitz, the Spracklens began their long term collaboration with Sidney Samole and Fidelity Electronics in the 80s. Sargon II already played the ACM 1978 still with the Jupiter III, and the WMCCC 1980, where it had to compete with its dedicated relatives, winner Chess Challenger, runner up Boris Experimental, Sargon 2.5 Modular GS and Sargon 2.5 Auto RB, and became tied third with 3/5, last game losing from Challenger.

Sargon III

Sargon III was a complete rewrite, using quiescence search, and a transposition table with BCH hashing. Sargon III was ported to the 68000, to be the first third-party executable software for the Macintosh [12]. The 8086 Sargon III port for PC was done by Kevin Leavelle in 1984 [13], so that three Sargon 3 software versions played the WMCCC 1984, where the Fidelity Electronics Elite by the same authors tied for first place, the Apple II became 10th with 4/7, the Macintosh 12th with 3½/7 and the 8088 Compaq PC 17th with 2½/7. In cooperation agreement between Fidelity Electronics and Software Toolworks in 1988, an enhanced and improved Sargon III was market as Fidelity Chessmaster 2100 [14].

Photos & Games


Mike Johnson 1 40 x 40.JPG

Kathe Spracklen and Mike Johnson, Mike vs. Sargon 2, ACM 1978 [15] [16]

[Event "ACM 1978"]
[Site "Washington USA"]
[Date "1978.12.04"]
[Round "3"]
[White "Mike"]
[Black "Sargon 2"]
[Result "1/2-1/2"]

1.e4 e5 2.d4 Nc6 3.d5 Nb4 4.c3 Na6 5.f4 Nc5 6.fxe5 Qh4+ 7.Kd2 Nxe4+ 8.Kc2 Nf2
9.Qe1 Bc5 10.Nf3 Qh5 11.Rg1 Ne7 12.Be3 Qg6+ 13.Kc1 Bxe3+ 14.Qxe3 Ng4 15.Qd2 d6
16.Bd3 Qh5 17.Bb5+ Bd7 18.Bxd7+ Kxd7 19.exd6 cxd6 20.h3 Nf6 21.Qg5 Qxg5+
22.Nxg5 Rhf8 23.c4 Rac8 24.Nd2 Nexd5 25.Kb1 Ne3 26.Nge4 Nxe4 27.Nxe4 Rxc4
28.Nc3 f5 29.a4 d5 30.g3 Rf6 31.Re1 d4 32.Nb5 a6 33.Nxd4 f4 34.gxf4 Rxd4
35.Rxe3 Rfxf4 36.a5 Rd1+ 37.Ka2 Ra4+ 38.Ra3 Rxa3+ 39.bxa3 Rd2+ 40.Kb3 Rd3+
41.Kc4 Rxh3 42.Rd1+ Kc6 43.a4 Rh5 44.Kb4 Rh4+ 45.Kb3 Rh3+ 46.Kc4 Rh5
47.Kb4 Rh4+ 48.Kb3 Rh3+ 49.Kc4 Rh5 50.Kb4 Rh4+ 1/2-1/2


Dan and Kathe Spracklen from their oral history on the Sargon 2 vs Awit game, round 4, ACM 1978 [17] [18]:

I think the most exciting part for us was the last round of the tournament, when we played Tony Marsland’s program Awit. It was a 6 million dollar Amdahl computer. And we won the game. And we were just amazed. I remember, at the time, we won it. And there was a huge audience there. There was like a hundred people sitting out there, watching it, and they just all started cheering and clapping. And then we woke up the following morning to a big article in the Washington Post that says, Microcomputer Beats 6 Million Dollar Machine, or something like that. 
[Event "ACM 1978"]
[Site "Washington USA"]
[Date "1978.12.05"]
[Round "4"]
[White "Sargon 2"]
[Black "Awit"]
[Result "1-0"]

1.e4 c5 2.d4 cxd4 3.Qxd4 Nc6 4.Qe3 Nf6 5.Nf3 e6 6.Nc3 Bb4 7.Bb5 a6 8.Bxc6 dxc6 
9.Bd2 Ng4 10.Qf4 Nf6 11.O-O O-O 12.Rad1 b5 13.Be3 Qa5 14.Bd4 Bxc3 15.Bxc3 Qxa2 
16.Bxf6 gxf6 17.Qxf6 Qc4 18.Qg5+ Kh8 19.Qf6+ Kg8 20.Qg5+ Kh8 21.Rd8 Rxd8 22.Qf6+ 
Kg8 23.Qg5+ Kf8 24.Qxd8+ Kg7 25.Qg5+ Kf8 26.Qd8+ Kg7 27.Qd4+ Qxd4 28.Nxd4 Bb7
29.Re1 Kg6 30.Re3 Rd8 31.Rd3 c5 32.Nxe6 Rxd3 33.Nf4+ Kg5 34.Nxd3 Bxe4 35.Nxc5 
Bxc2 36.Nxa6 Bb3 37.Nc5 Bd5 38.g3 Bf3 39.Nb3 b4 40.Nd4 Be4 41.f3 Bb7 42.Kf2 h6 
43.Ke3 Bd5 44.Nc2 b3 45.Nd4 Kg6 46.Kd3 Kh7 47.f4 Kg8 48.Kc3 Kg7 49.Nxb3 Bxb3 
50.Kxb3 Kf6 51.Kc4 Ke7 52.b4 Kd7 53.Kd5 h5 54.b5 Kc7 55.Kc5 Kb7 56.b6 Kb8 57.Kc6
Kc8 58.b7+ Kb8 59.Kb6 h4 60.gxh4 f6 61.h5 f5 62.Kc6 Ka7 63.Kc7 Ka6 64.b8=Q Ka5 
65.Qb3 Ka6 66.Qa4# 1-0

See also

Pages with Spracklen Quotes


1978 ...

1980 ...

2000 ...

Forum Posts


1990 ...

2000 ...

2010 ...

External Links

Sargon Z80 assembly listing by Dan and Kathe Spracklen, hosted by Andre Adrian

Sargon II

Apple II, Atari 8-bit, Commodore VIC-20, Commodore 64, TRS-80

Sargon II for VIC-20 (1982) - MobyGames
Sargon II for Commodore 64 (1983) - MobyGames
Sargon II (198?) Apple II cover art - MobyGames
Commodore 64 Emulator - Computer Chess Game Collection - Sargon II Chess from The Spacious Mind

Sargon III

Apple II, Amiga, Atari 8-bit, Atari ST, Commodore 64, Macintosh, PC

Sargon III for Apple II (1983) - MobyGames
Sargon III for DOS (1983) - MobyGames
Sargon III for Commodore 64 (1984) - MobyGames
Sargon III for Macintosh (1984) - MobyGames
Commodore 64 Emulator - Computer Chess Game Collection - Sargon III Chess from The Spacious Mind

Sargon 4

Macintosh, PC

Sargon 5

Macintosh, PC, Philips CD-i



  1. Sargon (chess) from Wikipedia
  2. Jupiter II-1975
  3. Dan Spracklen and Kathe Spracklen (1978). First Steps in Computer Chess Programming Byte Publications Inc., as pdf reprint from The Computer History Museum
  4. Sargon Z80 assembly listing by Dan and Kathe Spracklen, hosted by Andre Adrian
  5. Chris Morgan (1978). The Second West Coast Computer Faire. BYTE, Vol. 3, No. 7, hosted by Modern Mechanix, Photo 4: Ira Baxter’s chess playing system display, which competed in the Microcomputer Chess Tournament at the Faire. The level of play was impressive, and the winning program, called SARGON, was a 16 K byte Z-80 assembler program written by a husband and wife team, Kathe and Dan Spracklen.
  6. page 25 in Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
  7. Dan Spracklen and Kathe Spracklen (1978). SARGON: A Computer Chess Program. Hayden Bk.Co. ISBN: 978-0810451551,
  8. Hayden Software Co. - MobyGames
  9. page 30 in Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
  10. Chafitz ARB Sargon 2.5 from Wiki
  11. Great Game Machine
  12. Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
  13. Kevin Leavelle Video Game Credits and Biography - MobyGames
  14. Reply by Mark Manyen in Fidelity Chessmaster 2100 from The Spacious Mind
  15. Chess Computers - The UK Story from Chess Computer UK by Mike Watters
  16. PGN Download NACCC from Computerschaak/Downloads/Games hosted by CSVN
  17. page 35-36 in Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
  18. see also Harry Shershow (1979). A Little Bit is a Little Better. Personal Computing, Vol. 3, No. 4, pp. 61
  19. Re: Old programs CHAOS and USC by Dann Corbit, CCC, July 11, 2015

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