SYNC SOFTWARE PROFILE
Name of Package: ZX81 Chess.
ZX Chess II.
Type: Board Games
System: Sinclair 8K ROM; 16K RAM
Format: Cassette
Summary: Two powerful chess programs
Price: ZX81 Chess: £9.50.
ZX Chess II: £15.00
Manufacturer:
(ZX81 Chess)
Micro-Gen
24 Agar Crescent
Bracknell, Berkshire, U.K.
(ZX Chess II)
Artic Computing
396 James Reckitt Ave.
Hull, North Humberside, U.K.
Computer chess is becoming a very popular hobby for those who cannot find opponents on their level, and a large number of “dedicated” machines are appearing with increasingly greater strengths. Another area of growing popularity is designing a chess program which is more powerful (i.e., a better player) than other chess programs. Two powerful chess programs are now available for the 16K ZX81: ZX81 CHESS by Micro-Gen and ZX CHESS II by Artic Computing.
Both programs are supplied on cassette with detailed instructions. ZX81 CHESS has six levels of play; ZX CHESS II, seven. Both games set up a board and use the standard notation with rows 1 to 8 going up and A to F going left to right. ZX CHESS II also shows the letters of the columns and the numbers of the rows on the screen for quick reference when entering a move. The 24×24 board of ZX CHESS II is somewhat easier to use than the 16×16 board of ZX81 CHESS. The pieces are represented as follows: K King, Q = Queen, R = Rook, B = Bishop, N = Knight and I = Pawn. Black pieces are shown as black on white and white pieces as white on black.
Entering your move is simple on both programs. For example, to move a piece from position E2 to E4 you would enter E2-E4 on ZX CHESS and E2E4 on ZX CHESS II.
Both games make use of the En Passant privilege and display the move as PXPEP (pawn exchange pawn, En Passant). Castling is shown as 0-0 or 0-0-0 depending on the side. If you want to castle, you must enter the king’s move. You cannot castle out of check, and both programs stop and report invalid moves.
Both allow you to change sides, adjust the level of play, and alter some of the pieces half way through the game.
There are some differences. ZX CHESS II allows you to save the present board set-up on cassette, to COPY the screen onto the printer, and to print all the moves that have taken place in that game on the printer. On the higher levels you can even ask it to recommend your next move.
As a test to see which was the better chess player, I decided to pit them against each other. I chose level two on both. On this level ZX81 CHESS takes about a minute to decide its move while ZX CHESS II takes about forty seconds. A toss of a coin decided that ZX81 CHESS should go first. Chess enthusiasts will enjoy analyzing the match move by move. The final result was that ZX CHESS II won convincingly, with a Queen, a Rook, a Knight and two Pawn advantage! The final position of the pieces is shown in Figure 1.
Both games have levels for all players from beginner to postal chess. ZX CHESS II is clearly a better player and has more features than ZX81 CHESS, but it does cost £5-00 more. If you have a QS Character Board, there is a modified version of ZX CHESS II which shows real full-size pieces graphically, and very impressive it is, too.
Figure 1: A Game between ZX81 Chess and ZX Chess II
ZX81 Chess ZX Chess II 01 D2-D4 G8-F6 02 B1-C3 D7-D5 03 C1-F4 C8-F5 04 G1-F3 E7-E6 05 F4-G5 B8-D7 06 A2-A4 F8-D6 07 H2-H4 E8-G8 08 E2-E3 H7-H6 09 G5XF6 D8XF6 10 F1-D3 F5XD3 11 C2XD3 F6-F5 12 E1-G1 C7-C6 13 F1-E1 A8-C8 14 A4-A5 F8-E8 15 A5-A6 B7-B6 16 G2-G3 B6-B5 17 G1-G2 B5-B4 18 C3-E2 H6-H5 19 E1-H1 D7-F6 20 D1-C2 F6-D7 21 B2-B3 C6-C5 22 E2-F4 C5XD4 23 C2-E2 D4XE3 24 E2XE3 D6XF4 25 E3XF4 F5XD3 26 F4XB4 D7-C5 27 B4-D2 D3XB3 28 D2-G5 G7-G6 29 H1-B1 B3-D3 30 B1-D1 D3-C4 31 D1-D4 C4-B5 32 D4-F4 C5XA6 33 F4-A4 A6-B4 34 A4XA7 B4-C2 35 A1-A5 B5-B4 36 A5-A4 B4-C5 37 A7-A5 C5-C3 38 A5-A7 C8-C4 39 A4XC4 D5XC4 40 F3-E5 C2-E1 41 G2-G1 C3XE5 42 G5XE5 E1-F3 43 G1-F1 F3XE5 44 A7-A5 E5-D7 45 F1-G2 C4-C3 46 A5-G5 C3-C2 47 G5XG6 F7XG6 48 F2-F3 C2-C1 49 G2-F2 C1-D2 50 F2-G1 D2-E3 51 G1-G2 E3-E2 52 G2-H3 E2XF3 53 H3-H2 G8-H7 54 G3-G4 F3XG4 55 H2-H1 G4-H3 56 H1-G1 H3XH4 57 G1-G2 H4-F4 58 G2-H3 F4-G5 59 H3-H2 H5-H4 60 H2-H1 H4-H3 61 H1-H2 G5-G2