GO 9x9 128K FOR THE ZX SPECTRUM
© LAWLORD 2026, version 2.0 (tape 2.0.1)

The game of Go on a 9x9 board, against the computer or for two
players. Runs on the ZX Spectrum 128K, +2, +2A, +3 and Pentagon. This
is the 128K version: it is stronger and uses all of the machine's
memory. For the 48K there is a separate version 1.3.


LOADING

go9x9_128k_v2.0.1.tap is the tape. On the 128K and +2 choose Tape
Loader from the menu, on the +2A and +3 choose Loader. Do not load it
from 48 BASIC: the game would not have its memory and the screen
shows 128K MODE NEEDED. First a picture loads, then the game loads
under it, all at once; loading takes about ten minutes.

go9x9_128k_v2.0.z80 is a memory snapshot for emulators; the game
starts at once. The file says it is for the 128K, so the emulator
switches by itself.


MENU

After loading, and before every new game, the menu shows the
settings:

  1  BLACK     YOU
     WHITE     COMPUTER
  2  LEVEL     30 SEC A MOVE
  3  HANDICAP  NONE
     KOMI      7
  4  KEMPSTON  JOYSTICK OFF
     ENTER     START

Key 1 chooses who plays which colour: you Black and the computer
White, the computer Black and you White, or two players.
Key 2 chooses the computer's time per move: 10, 20, 30, 60 or 120
seconds (with two players the line is empty).
Key 3 chooses the handicap: none, 2, 3, 4 or 5 stones.
Key 4 turns the Kempston joystick on or off (it is off at first).
Each key goes round its choices; ENTER starts the game (with the
joystick on, Fire starts it too).


KEMPSTON JOYSTICK

With the joystick on, a square cursor appears on the board. The
joystick moves it, and Fire plays there, as if you typed the
coordinate and pressed ENTER; the keys work as before. After two
passes, Fire on a stone marks it dead or alive, and Fire on an empty
point counts the score.

Turn it on only with a Kempston interface, or in an emulator set to
Kempston. Sinclair and Cursor joysticks are not supported: their keys
are the digits used for the rows.


MAKING A MOVE

Column letter (A-H and J; there is no I on the board), row digit,
ENTER. For example: E, 5, ENTER.

What you type appears on the panel after the ">" sign. The letter
and the digit can be typed in either order; a new letter or digit
replaces the previous one. CAPS SHIFT + 0 (DELETE) clears the input.

The last move is marked with a dot on the stone.


KEYS

P   pass.
U   take back a move. Against the computer it takes back its move
    and yours.
N   new game, which also means resigning. Answer Y to the question
    NEW?, then the menu appears; any other key returns to the game.
The menu settings can also be changed during a game:
K   handicap: 0, 2, 3, 4 or 5 stones.
S   which side the computer plays: White (S CPU W); nobody, for two
    players (S 2 PL.); Black (S CPU B).
L   the computer's time per move: 10, 20, 30, 60 or 120 seconds.
    Takes effect from its next move.


PANEL

MOVE             move number
BLACK TO PLAY    Black to move (or WHITE TO PLAY)
CAPT. B, W       stones captured by Black and by White
THINK            the computer is thinking
I PASS           the computer passed
WHITE RESIGNS    the computer resigned (BLACK RESIGNS if it played
                 Black)
TAKEN            the point is occupied
KO               the move is forbidden by the ko rule
SUICIDE          suicide is not allowed
SUPERKO          the move would repeat an earlier position
FULL             the game has 255 moves, no more can be recorded


RULES

Area scoring (Chinese rules): one point for each of your stones on
the board and for each empty point of your territory.
White gets 7 points komi, so a draw (JIGO) is possible.
Suicide is not allowed. A position that has already occurred in the
game may not be repeated (positional superko).


HANDICAP

2 to 5 stones, chosen in the menu or with key K. They are placed on
G7, C3, G3, C7, E5 (in this order). White moves first; komi is 0.5
points. Key K before the first move sets the handicap up at once;
during a game it applies from the next game.


END OF THE GAME

The game ends after two passes in a row.

The computer marks the dead stones itself with a cross; while it is
thinking, the panel shows WAIT. If you disagree, type the coordinate
of a stone and press ENTER: the mark of the whole chain is switched.
ENTER without a coordinate counts the score. The panel reminds you
of this: DEAD:A1 and ENT=END.

Black's territory is marked with filled squares, White's with hollow
ones. The panel shows both scores (B 45, W 36) and the result: the
winner's letter and the margin including komi, for example B+2 or
W+3.5.

If a pass was a mistake, key U returns to the game before counting.

If you pass, the computer counts the score the same way as at the
end of the game, with the dead stones it sees, so it thinks a few
seconds longer then. If it is winning, it passes too. If there are
still open areas on the board that belong to nobody, it plays on,
however often you pass. If the board is divided and it is losing
by 15 points or more, it resigns. Otherwise it fills the remaining
dame (empty points between its stones and yours) or makes one more
try; when you pass again and no dame is left, it passes too and
the game goes to counting.
In a hopeless position the computer resigns.


THE COMPUTER

The time per move is kept on average. In the opening the computer
often moves at once from its opening book; in clear positions it
moves faster, and the time saved goes to the difficult moves.

While you think, the computer also thinks about your possible
moves. Keys pressed while the computer is thinking take effect
after its move.

It reads ladders: it knows when a string in atari that runs away
will still be captured by a ladder.

The 128K version uses all of the machine's memory:
- about 8,000 shapes of the stones around a move (the 12 nearest
  points), learned from games of the program KataGo: the computer
  chooses better which moves to think about;
- a tree of variations of about 1,000 positions in a bank of its
  own (the 48K one had 700): the more time it has, the deeper it
  reads, so it is clearly stronger at 60 and 120 seconds;
- an opening book of 8,000 positions with the most frequent human
  replies.


CHANGES IN VERSION 2.0.1 (THE TAPE ONLY)

The tape also loads when LOAD "" is typed in 48K mode on a 128K
machine with its memory free (after USR 0), as some emulators do,
the one on ZX-Art among them. The game itself is the same as 2.0.


CHANGES IN VERSION 2.0 (128K)

A separate version for the 128K, clearly stronger than 1.3 (at 30
seconds with no handicap it wins about three games out of four
against it): the shapes around a move, a big tree of variations, an
opening book of 8,000 positions.
A level of 120 seconds a move.
The end of the game after your passes: on a divided board the
computer fills the dame, then passes, or resigns when far behind,
instead of playing stone after stone; while open areas remain, it
plays on.
128K on the loading screen and in the menu.


CHANGES IN VERSION 1.3

A loading screen.


CHANGES IN VERSION 1.2

The Kempston joystick (menu key 4): a cursor on the board, Fire to
play.


CHANGES IN VERSION 1.1

The menu before the game.
The computer reads ladders.
No more mistaken passes: the computer now counts the score properly
before agreeing to end the game.
