Difference between revisions of "Programming:Logarithm"

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(added logarithm)
 
m (forgot the category :()
 
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ret
 
ret
 
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</pre>
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[[Category:Programming]]

Latest revision as of 16:46, 18 April 2011

Log of base 2

; input: hl (unsigned)
; output: a = log2(hl) (rounded down and from -1 to 15) (8-bit integer signed)
log2:
	ld	a, 16
	scf
log2loop:
	adc	hl, hl
	dec	a
	jr	nc, log2loop
	ret