43 lines
602 B
ArmAsm
43 lines
602 B
ArmAsm
.define .inn2
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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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! Bit test on 16 bits set
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! Expects on stack: bit number
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! set to be tested
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! Yields in de-registers: 0 if bit is reset or bit number out of range
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! 1 if bit is set
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.inn2: pop h
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shld .retadr
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pop d !bit number
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pop h !set to be tested
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mov a,e
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cpi 16
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jnc 3f
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cpi 8
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jnc 1f
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mov e,a
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mov a,l !l-reg contains the wanted bit
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jmp 2f
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1: sbi 8
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mov e,a
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mov a,h !h-reg contains the wanted bit
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2: dcr e
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jm 4f
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rar
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jmp 2b
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3: xra a !return 0 if bit number out of range
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4: ani 1
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mov e,a
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mvi d,0
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lhld .retadr
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pchl
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