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扩展data段，完成食物生成

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fumiama
2021-04-04 23:05:36 +08:00
parent 743e7c939d
commit 16b49bd98d
8 changed files with 104 additions and 17 deletions
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84
addfood.asm
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@@ -3,5 +3,87 @@
;;;;;;;;;;;;;;;;;;;;;;;;;;;;
addfood:
.scope
.data
.space seed 6
.text
lda #<field
sta _ptr
lda #>field
sta _ptr + 1
`propagate seed, $c3
`propagate seed+1, $9e
`propagate seed+2, $26
`propagate seed, seed+1
`propagate seed+1, seed+2
`propagate seed+2, seed+3
lda seed + 5
ldx seed + 4
sta seed + 4
lda seed + 3
stx seed + 3
ldx seed + 2
sta seed + 2
lda seed + 1
stx seed + 1
ldx seed
sta seed
stx seed + 5
lda seed
tay
lda seed + 1
and #$03
beq +
clc
adc _ptr + 1
sta _ptr + 1
* cmp #$03
bne +
tya
cmp #$c0
bmi +
sbc #$c0
tay
* lda (_ptr), y
iny
cmp #csnk
beq -
cmp #cblk
beq -
lda #csnk
dey
sta (_ptr), y
rts
.scend
.scend
srand: ; 做随机种子的初始化
.scope
jsr rdtim
sta seed + 5
stx seed + 3
sty seed + 1
rts
.scend
;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; propagate 进位
;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.macro propagate
lda _1
clc
adc _2
bcc _end
inc _1 + 1
bne _end
inc _1 + 2
bne _end
inc _1 + 3
bne _end
inc _1 + 4
bne _end
inc _1 + 5
_end:
sta _1
.macend