tictactoe.asm

;Tic Tac Toe by Ben Van Oss

.org $9000

start:
    ld hl, msg
    rst 28h

game:
    ld hl, rowG
    rst 28h
    rst 10h
    ld bc, $3133
    call cmp
    ld hl, colG
    rst 28h
    rst 10h
loop:
    ld ix, board
    ld a, 'X'
    ld (ix+d), a
    ld hl, board
    rst 28h
    jp game

cmp:
    cp c + 1
    jp nc,err
    cp b - 1
    jp nc,err
    bit 5,a
    jp nz,de ;d for $4*, e for $3*
    res 4, a
    res 5, a
    res 6, a
    res 7,a
    ld e,a
    ret
de:
    res 4,a
    res 5,a
    res 6,a
    res 7,a
    ld d,a
    ret

err:
    ld hl, noCmd
    jp game


msg:
    .db "Tic Tac Toe v0.1 by Ben Van Oss",0

rowG:
    .db "Row: ",0
colG:
    .db "Columb: ",0
noCmd:
    .db "Not a valid entry.",0

board:
    .db "  |  |  ",$0D
    .db "--------",$0D
    .db "  |  |  ",$0D
    .db "--------",$0D
    .db "  |  |  ",0