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21 lines
419 B
NASM
21 lines
419 B
NASM
; just for tests - DISFUNCTIONAL!
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math_store_reg .byte 0 ; temporary storage
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multiply_bytes .proc
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; -- multiply 2 bytes A and Y, result as byte in A (signed or unsigned)
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sta P8ZP_SCRATCH_B1 ; num1
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sty P8ZP_SCRATCH_REG ; num2
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lda #0
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beq _enterloop
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_doAdd clc
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adc P8ZP_SCRATCH_B1
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_loop asl P8ZP_SCRATCH_B1
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_enterloop lsr P8ZP_SCRATCH_REG
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bcs _doAdd
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bne _loop
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rts
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.pend
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