ROR (SPC700): Difference between revisions

Latest revision as of 19:34, 4 August 2024


Basic Info
Addressing Mode	Opcode	Length	Speed
Accumulator	7C	1 byte	2 cycles
Direct Page	6B	2 bytes	4 cycles
Direct Page Indexed by X	7B	2 bytes	5 cycles
Absolute	6C	3 bytes	5 cycles


Flags Affected
N	V	P	B	H	I	Z	C
N	.	.	.	.	.	Z	C

ROR is an SPC700 instruction that rotates every bit of its operand one bit to the right. The old value of the carry flag is rotated into the most significant bit. The least significant bit is rotated into the carry flag. A total of 9 bits are rotated.

The official manual has the bit shift operators for ROR pointing the wrong way.

Syntax

ROR A
ROR dp
ROR dp+X
ROR !abs

External Links

Official Super Nintendo development manual on ROR: Appendix C-7 of Book I
anomie: https://github.com/yupferris/TasmShiz/blob/master/spc700.txt#L554

@@ Line 1: / Line 1: @@
-'''ROR''' is an [[SPC700]] instruction that rotates to the right.
+{| class="wikitable" style="float:right;clear:right;width:40%"
-{| class="wikitable" style="float:right;clear:right;width:30%"
 !colspan="8"|Basic Info
 |+
@@ Line 9: / Line 7: @@
 |'''Speed'''
 |+
-|
+|[[Accumulator Addressing | Accumulator]]
 |7C
 |1 byte
 |2 cycles
 |+
-|
+|[[Direct Page Addressing | Direct Page]]
 |6B
 |2 bytes
 |4 cycles
 |+
-|
+|[[Direct Page Indexed by X]]
 |7B
 |2 bytes
 |5 cycles
 |+
-|
+|[[Absolute Addressing | Absolute]]
 |6C
 |3 bytes
@@ Line 31: / Line 29: @@
 {| class="wikitable" style="float:right;clear:right;width:30%"
-!colspan="8"|Flags Clobbered
+!colspan="8"|Flags Affected
+|+
+|[[Negative Flag|N]]
+|[[Overflow Flag|V]]
+|[[Direct Page Flag|P]]
+|[[Break Flag|B]]
+|[[Half-Carry Flag|H]]
+|[[Interrupt Enable Flag|I]]
+|[[Zero Flag|Z]]
+|[[Carry Flag|C]]
 |+
 |N
-|V
-|P
-|B
-|H
-|I
-|Z
-|C
-|+
-|
 |.
 |.
@@ Line 48: / Line 46: @@
 |.
 |.
-|
+|Z
-|
+|C
 |}
+'''ROR''' is an [[SPC700]] instruction that rotates every bit of its operand one bit to the right.  The old value of the [[carry flag]] is rotated into the most significant bit.  The least significant bit is rotated into the carry flag.  A total of 9 bits are rotated.
+The official manual has the bit shift operators for ROR pointing the wrong way.
+==== Syntax ====
+<pre>
+ROR A
+ROR dp
+ROR dp+X
+ROR !abs
+</pre>
+[[File:ror.png]]
+=== See Also ===
+* [[ROL (SPC700)]]
+* [[LSR (SPC700)]]
+* [[ROR]]
+* [[ROR (Super FX)]]
 === External Links ===
-* Official Nintendo documentation on ROR: https://archive.org/details/SNESDevManual/book1/page/n232
+* Official Super Nintendo development manual on ROR: [https://archive.org/details/SNESDevManual/book1/page/n232 Appendix C-7 of Book I]
+* anomie: https://github.com/yupferris/TasmShiz/blob/master/spc700.txt#L554
 [[Category:ASM]]
 [[Category:SPC700]]
 [[Category:Shift Rotation Commands]]