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--- base:8bit_multiplication_16bit_product_fast_no_tables [2020-02-02 21:59] – created djmips
+++ base:8bit_multiplication_16bit_product_fast_no_tables [2020-02-02 22:08] – djmips
@@ Line 1: / Line 1: @@
+<code>
 ; mul 8x8 16 bit result for when you can't afford big tables
 ; by djmips
 ;
-; inputs are mul1 and mul2 and A should be zero
+; inputs are mul1 and mul2 and should be zero page.
-; output is 16 bit in A : mul1
+; A should be zero entering but if you want it will factor in as 1/2 A added to the result.
+;
+; output is 16 bit in A : mul1   (A is high byte)
 ;
 ; total cycles worst case = 113
@@ Line 47: / Line 50: @@
      inc mul2  ; 5
      rts
+</code>