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|
; "spacer", move a space ship through an
; endless tunnel. You die once you hit
; the walls.
;
; Controls:
;
; W - move up
; X - move down
; Any other key will stop the ship
;
; Ps: this game runs awfully slow =)
;
start:
jsr init
loop:
;; jsr drawShip
jsr drawMap
jsr genMap
jsr readKeys
jmp loop
;--
drawShip:
lda $82 ; mychange
; asl
tay
lda ypos,y
sta $00
iny
lda ypos,y
sta $01
ldx #42
lda ($00,x)
cmp #0
beq noCrash
cmp #5
; bne crashed
;my changes
noCrash:
lda #5
sta ($00,x)
lda $60
cmp $61
beq ret
lda $61
asl
tay
lda ypos,y
sta $00
iny
lda ypos,y
sta $01
lda #0
ldx #42
sta ($00,x)
lda $60
sta $61
ret:
rts
;--
crashed:
lda $fe
sta ($00,x)
jmp crashed
;--
readKeys:
lda $ff
cmp #119
bne notUp
dec $60
rts
notUp:
cmp #120
bne noMove
inc $60
noMove:
rts
;--
init:
ldx #0
drawLogo:
lda bottomLogo,x
sta $500,x
inx
cpx #0
bne drawLogo
lda #10
sta $60
sta $61
ldx #0
lda #$c
c:sta $200,x
sta $400,x
dex
cpx #0
bne c
lda #16
sta $80 ; origin
ldx #15
set:
sta $81,x ; target
dex
bpl set
rts
;--
drawMap:
lda #0
sta $78
lda #32
sta $79
lda #192
sta $7a
lda #224
sta $7b
ldx #15
drawLoop:
lda $81,x
sta $82,x
tay
lda ypos,y
sta $00
iny
lda ypos,y
sta $01
lda #$c
ldy $78
sta ($00),y
iny
sta ($00),y
ldy $7b
sta ($00),y
iny
sta ($00),y
ldy $79
lda #0
sta ($00),y
iny
sta ($00),y
ldy $7a
sta ($00),y
iny
sta ($00),y
inc $78
inc $79
inc $7a
inc $7b
inc $78
inc $79
inc $7a
inc $7b
dex
bpl drawLoop
rts
;---
genMap:
lda $80
cmp $81
beq done
lda $80
clc
sbc $81
bpl plus
bmi minus
done:
lda $fe
and #$f
asl
sta $80
rts
minus:
dec $81
dec $81
rts
plus:
inc $81
inc $81
rts
ypos:
dcb $00,$02,$20,$02,$40,$02,$60,$02
dcb $80,$02,$a0,$02,$c0,$02,$e0,$02
dcb $00,$03,$20,$03,$40,$03,$60,$03
dcb $80,$03,$a0,$03,$c0,$03,$e0,$03
dcb $00,$04,$20,$04,$40,$04,$60,$04
dcb $80,$04,$a0,$04,$c0,$04,$e0,$04
dcb $00,$05,$20,$05,$40,$05,$60,$05
dcb $80,$05,$a0,$05,$c0,$05,$e0,$05
bottomLogo:
dcb $0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0
dcb $0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0,$0
dcb $0,$0,$0,$0,$0,$0,$1,$1,$1,$6,$1,$1,$1,$0
dcb $0,$6,$1,$1,$6,$0,$0,$1,$1,$1,$6,$0,$1,$1
dcb $1,$0,$1,$1,$1,$6,$0,$0,$6,$1,$6,$0,$6,$0
dcb $1,$0,$6,$1,$6,$1,$6,$0,$1,$0,$1,$0,$6,$0
dcb $6,$1,$6,$0,$6,$0,$1,$0,$6,$1,$6,$0,$0,$6
dcb $1,$1,$6,$6,$1,$1,$1,$0,$6,$1,$0,$0,$1,$0
dcb $1,$6,$0,$6,$6,$1,$1,$1,$0,$6,$1,$0,$6,$1
dcb $0,$6,$6,$6,$6,$6,$1,$6,$1,$1,$6,$6,$6,$1
dcb $1,$1,$1,$6,$1,$6,$6,$6,$6,$1,$6,$6,$6,$6
dcb $1,$1,$1,$6,$6,$6,$6,$1,$1,$1,$1,$e,$1,$1
dcb $e,$6,$6,$1,$1,$6,$1,$6,$1,$1,$1,$1,$e,$1
dcb $1,$1,$1,$6,$1,$1,$6,$1,$6,$6,$6,$1,$1,$1
dcb $6,$e,$1,$1,$6,$e,$6,$1,$1,$e,$1,$e,$6,$1
dcb $1,$1,$6,$e,$1,$1,$1,$e,$1,$1,$6,$1,$6,$e
dcb $e,$e,$6,$e,$e,$6,$e,$e,$6,$e,$e,$6,$e,$e
dcb $6,$e,$e,$6,$e,$e,$6,$e,$e,$6,$e,$e,$6,$e
dcb $e,$6,$e,$e
|
