the San Jose City College Open in January 1980. Sargon 3.0 finished in seventh place at the October 1979 North American Computer Chess Championship. The competition had improved, but 3.0 drew against Cray Blitz and easily defeated Mychess, its main microcomputer rival. In December, 3.0 easily won the second microcomputer championship in London. Sargon III was a complete rewrite. Instead of an exchange evaluator, this version used a capture search algorithm. Also included was a chess opening repertoire. This third version was written originally for the 6502 assembler. In 1978, Sargon was converted to Z80 neumonics/assembler code by Paul H. Lohnes, as self taught computer enthusiast while he was still in the US Navy. He sold the publishing rights to Hayden Software for the Radio Shack TRS-80 platform. It was commercially published for other computing platforms by Hayden Software in 1983. Apple contacted the Spracklens and, after a port for 68000 assembly, Sargon III was the first third-party executable software for the Macintosh. Legacy After the demise of Hayden Software, later chess programs were also released under the name Sargon, including Sargon 4 (Spinnaker Software), Sargon V (Activision) and a CD-i title simply named Sargon Chess. 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 three-time world chess champion Mikhail Botvinnik played a game with Sargon in 1983 at Hamburg. He did not play his best moves but 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 Notes References External links 1978 video games Apple II games Chess software Commercial video games with freely available source code Commodore 64 games VIC-20 games CP/M games Assembly language software Video games developed in the United States