REP: Difference between revisions

Latest revision as of 16:52, 14 December 2023


Basic Info
Addressing Mode	Opcode	Length	Speed
Immediate	C2	2 bytes	3 cycles


Flags Affected
	N	V	M	X	D	I	Z	C
emulation mode			.	.
native mode

REP (Reset Status Bits) is a 65c816 instruction that clears bits in the status register that correspond to set bits in the operand.

REP appears to be the only way to clear the m and x flags other than PLP and RTI.

External Links

Eyes & Lichty page 489, on REP: https://archive.org/details/0893037893ProgrammingThe65816/page/n515
Labiak page 173 on REP: https://archive.org/details/Programming_the_65816/page/n183
snes9x implementation of REP: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L3145
undisbeliever on REP: https://undisbeliever.net/snesdev/65816-opcodes.html#rep-reset-status-bits

@@ Line 1: / Line 1: @@
-'''REP''' is a [[65c816]] instruction that clears bits in the [[status register]] that correspond to set bits in the operand.
+{| 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'''
 |+
-|immediate
+|[[Immediate]]
 |C2
 |2 bytes
@@ Line 15: / Line 13: @@
 |}
-{| class="wikitable" style="float:right;clear:right;width:30%"
+{| class="wikitable" style="float:right;clear:right;width:40%"
-!colspan="8"|Basic Info
+!colspan="9"|Flags Affected
+|+
+|
+|[[Negative Flag|N]]
+|[[Overflow Flag|V]]
+|[[M Flag|M]]
+|[[X Flag|X]]
+|[[Decimal Flag|D]]
+|[[I Flag|I]]
+|[[Zero Flag|Z]]
+|[[Carry Flag|C]]
 |+
-|'''Addressing Mode'''
+| [[emulation mode]]
-|'''Opcode'''
+|
-|'''Length'''
+|
-|'''Speed'''
+|.
+|.
+|
+|
+|
+|
 |+
-|implied
+| [[native mode]]
-|78
+|
-|1 byte
+|
-|2 cycles
+|
+|
+|
+|
+|
+|
 |}
+'''REP''' (Reset Status Bits) is a [[65c816]] instruction that clears bits in the [[status register]] that correspond to set bits in the operand.
+REP appears to be the only way to clear the m and x flags other than [[PLP]] and [[RTI]].
 === See Also ===
 * [[SEP]]
+* [[CLC]]
+* [[CLV]]
+* [[CLD]]
+* [[CLI]]
+=== External Links ===
+* [[Eyes & Lichty]] page 489, on REP: https://archive.org/details/0893037893ProgrammingThe65816/page/n515
+* [[Labiak]] page 173 on REP: https://archive.org/details/Programming_the_65816/page/n183
+* snes9x implementation of REP: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L3145
+* undisbeliever on REP: https://undisbeliever.net/snesdev/65816-opcodes.html#rep-reset-status-bits
 [[Category:ASM]]
+[[Category:65c816 additions]]
+[[Category:Two-byte Instructions]]
+[[Category:Three-cycle Instructions]]
+[[Category:Single Admode Mnemonics]]