Differences

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--- base:16-bit_comparison [2020-10-22 20:30] – created tww
+++ base:16-bit_comparison [2020-10-24 14:05] – [TWW Method] verz
@@ Line 17: / Line 17: @@
     lda val1
-    sec
+    ;sec
-    sbc val2
+    ;sbc val2
+    cmp val2
     php
     lda val1+1
@@ Line 26: / Line 27: @@
     sta temp
     pla
-    and #%00000010
+    ;and #%00000010  ; useless because of the following ORA
     ora #%11111101
     and temp
@@ Line 42: / Line 43: @@
+Different approach: instead of setting flags, goes to different destinations:
+<code>
+; Val1 ≥ Val2 ?
+  LDA Val1 +1    ; high bytes
+  CMP Val2+1
+  BCC LsThan     ; hiVal1 < hiVal2 --> Val1 < Val2
+  BNE GrtEqu     ; hiVal1 ≠ hiVal2 --> Val1 > Val2
+  LDA Val1       ; low bytes
+  CMP Val2
+  ;BEQ Equal     ; Val1 = Val2
+  BCS GrtEqu     ; loVal1 ≥ loVal2 --> Val1 ≥ Val2
+LsThan
+...
+GrtEqu
+...
+</code>