Differences

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--- playground:reversing_bits_in_a_byte [2020-02-20 21:15] – asl verz
+++ playground:reversing_bits_in_a_byte [2020-03-12 13:05] (current) – tlr
@@ Line 51: / Line 51: @@
         asl
         lda $2
-        rol
+        ror
         rts
+</code>
+--
+Optimized version, at 84cycl +rts (enter with the value in .A, result in .A)
+<code>
+	sta	$02	; 3
+	lda	#1	; 2
+lp:
+	ror	$02	; 5
+	rol		; 2
+	bcc	lp	; 3(2)
+			; =84
+	rts
+</code>
+or slightly unrolled:
+<code>
+	sta	$02	; 3
+	lda	#1	; 2
+lp:
+	ror	$02	; 5
+	rol		; 2
+	ror	$02	; 5
+	rol		; 2
+	bcc	lp	; 3(2)
+			; =72
+	rts
 </code>