36 lines
607 B
ArmAsm
36 lines
607 B
ArmAsm
.define .los
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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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.los:
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pop ix ! save return address
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pop de ! number of bytes to transfer
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pop hl ! address of lowest byte
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add hl,de
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dec hl ! address of highest byte
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srl d ! divide de by 2
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rr e
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jr nc,1f ! see if de was odd
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ld a,e ! yes, then it must be 1
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or d
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jr nz,.trp.z ! no, error
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ld e,(hl) ! pack 1 byte into integer
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push de
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jp (ix) ! return
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1:
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ld b,(hl) ! get 2 bytes
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dec hl
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ld c,(hl)
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dec hl
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push bc ! put them on stack, most
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! significant byte first
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dec de
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ld a,d
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or e
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jr nz,1b ! done ?
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jp (ix) ! yes, return
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