woz64/math.asm

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#importonce
.filenamespace Math
#import "mem_map.asm"
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.pc = * "Math Routines"
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multiply: {
stx MemMap.MATH_SPACE.multiTmpX
pha
lda #$00
ldx #$08
clc
m0: bcc.r m1
clc
adc MemMap.MATH_SPACE.factor2
m1: ror
ror MemMap.MATH_SPACE.factor1
dex
bpl.r m0
ldx MemMap.MATH_SPACE.factor1
sta MemMap.MATH_SPACE.result
stx MemMap.MATH_SPACE.result+1
pla
ldx MemMap.MATH_SPACE.multiTmpX
rts
}