RETI (SPC700): Difference between revisions

Latest revision as of 19:25, 4 August 2024


Basic Info
Addressing Mode	Opcode	Length	Speed
Stack	7F	1 byte	6 cycles


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

RETI (RETurn from Interrupt) is an SPC700 instruction that returns from an interrupt handler. All program status word flags are popped off the stack and restored. The program counter is also popped from the stack.

As the S-SMP has no hardware interrupt sources, this generally means returning from a BRK.

RETI

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 {| 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
@@ Line 24: / Line 33: @@
 |Z
 |C
-|+
-|
-|
-|
-|
-|
-|
-|
-|
 |}
-'''RETI''' (RETurn from Interrupt) is an [[SPC700]] instruction that returns from an interrupt.  All [[program status word]] flags are restored after being popped off the [[stack]].  The [[program counter]] is also popped from the stack.
+'''RETI''' (RETurn from Interrupt) is an [[SPC700]] instruction that returns from an [[interrupt handler]].  All [[program status word]] flags are popped off the [[stack]] and restored.  The [[program counter]] is also popped from the stack.
+As the S-SMP has no hardware interrupt sources, this generally means returning from a [[BRK (SPC700)|BRK]].
+==== Syntax ====
+<pre>
+RETI
+</pre>
 === See Also ===
+* [[EI]]
+* [[DI]]
 * [[RET]]
+* [[RTI]]
 * [[RTS]]
+* [[RTL]]
 === References ===
 * Table C-16 in [https://archive.org/details/SNESDevManual/book1/page/n234 Appendix C-9 of Book I] of the official Super Nintendo development manual
+* anomie: https://github.com/yupferris/TasmShiz/blob/master/spc700.txt#L547
 [[Category:ASM]]
 [[Category:SPC700]]
 [[Category:Subroutine Call Return Commands]]
+[[Category:One-byte Instructions]]