55 lines
774 B
ArmAsm
55 lines
774 B
ArmAsm
.define .loi
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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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! Load indirect
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! Expects in de-registers: number of bytes to be loaded
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! (this number should be 1 or even )
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! Expects on stack: base address
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! Yields on stack: result
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.loi: pop h
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shld .retadr
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mov l,c ! free bc for scratch
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mov h,b
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shld .bcreg
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pop h ! hl = base address
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dad d ! hl = load pointer
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xra a ! clear carry bit
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mov a,d ! divide d by 2
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rar
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mov d,a
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mov a,e
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rar
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mov e,a
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jnc 1f
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! if 1 byte has to be loaded only:
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mov a,d
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ora e
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cnz eoddz ! trap if number is odd and <> 1
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dcx h
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mov c,m
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mvi b,0
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push b
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jmp 2f
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1: dcx h
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mov b,m
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dcx h
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mov c,m
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push b
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dcx d ! is count exhausted?
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mov a,d
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ora e
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jnz 1b
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2: lhld .bcreg
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mov c,l
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mov b,h
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lhld .retadr
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pchl
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