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

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-'''ROR''' is an [[SPC700]] instruction that rotates 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.
+'''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.
@@ Line 61: / Line 61: @@
 ROR !abs
 </pre>
+[[File:ror.png]]
 === See Also ===
 * [[ROL (SPC700)]]
+* [[LSR (SPC700)]]
 * [[ROR]]
 * [[ROR (Super FX)]]
@@ Line 69: / Line 72: @@
 === External Links ===
 * 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]]