36 lines
511 B
ArmAsm
36 lines
511 B
ArmAsm
.define .rck
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.sect .text
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.sect .rom
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.sect .data
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.sect .bss
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.sect .text
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.rck:
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pop bc
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pop ix
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3: pop hl
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push hl
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ld e,(ix)
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ld d,(ix+1)
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ld a,h
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xor d ! check sign bit to catch overflow with subtract
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jp m,1f
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sbc hl,de
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jr 2f
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1: xor d ! now a equals (original) h again
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2: call m,e.rck
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pop de
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push de
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ld l,(ix+2)
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ld h,(ix+3)
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ld a,h
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xor d ! check sign bit to catch overflow with subtract
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jp m,1f
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sbc hl,de
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jr 2f
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1: xor d ! now a equals (original) h again
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2: call m,e.rck
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push bc
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pop ix
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jp (ix)
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