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+====== 16-bit Division ======
+To make the most common integer multiplication/division routines complete:
+<code>
+divisor = $58     ;$59 used for hi-byte
+dividend = $fb	  ;$fc used for hi-byte
+remainder = $fd	  ;$fe used for hi-byte
+result = dividend ;save memory by reusing divident to store the result
+divide	lda #0	        ;preset remainder to 0
+	sta remainder
+	sta remainder+1
+	ldx #16	        ;repeat for each bit: ...
+divloop	asl dividend	;dividend lb & hb*2, msb -> Carry
+	rol dividend+1
+	rol remainder	;remainder lb & hb * 2 + msb from carry
+	rol remainder+1
+	lda remainder
+	sec
+	sbc divisor	;substract divisor to see if it fits in
+	tay	        ;lb result -> Y, for we may need it later
+	lda remainder+1
+	sbc divisor+1
+	bcc skip	;if carry=0 then divisor didn't fit in yet
+	sta remainder+1	;else save substraction result as new remainder,
+	sty remainder
+	inc result	;and INCrement result cause divisor fit in 1 times
+skip	dex
+	bne divloop
+	rts
+</code>
+Variations of the above routine have been published in several C=64 mags. In terms of speed AND memory usage it should be the optimum.