BVS (Super FX): Difference between revisions

Latest revision as of 08:04, 14 July 2024


Basic Info
Addressing Mode	Opcode	Length	ROM Speed	RAM Speed	Cache Speed
Program Counter Relative	0F??	2 bytes	6 cycles	6 cycles	2 cycles


Flags Affected
B	ALT1	ALT2	O/V	S	CY	Z
.	.	.	.	.	.	.

BVS (Branch Overflow Set) is a Super FX instruction that performs a branch when the overflow flag (O/V) is set. The instruction following BVS is already in the pipeline and will run even if the branch occurs.

If the overflow flag is clear, control simply falls through and the branch does not happen.

No flags are affected.

Syntax

BVS e

Example

Let the O/V flag be set. This instruction jumps the program backward 2 bytes:

 BVS $-2h

External Links

Official Nintendo documentation on BVS: 9.26 on Page 2-9-36 of Book II
example: Page 2-9-37 of Book II, lbid.

@@ Line 1: / Line 1: @@
-{| class="wikitable" style="float:right;clear:right;width:40%"
+{| class="wikitable" style="float:right;clear:right;width:50%"
 !colspan="8"|Basic Info
 |+
+|'''Addressing Mode'''
 |'''Opcode'''
 |'''Length'''
@@ Line 8: / Line 9: @@
 |'''Cache Speed'''
 |+
+|[[Program Counter Relative]]
 |0F??
 |2 bytes
@@ Line 24: / Line 26: @@
 |[[Sign Flag|S]]
 |[[CY]]
-|Z
+|[[Zero Flag|Z]]
 |+
 |.
@@ Line 35: / Line 37: @@
 |}
-'''BVS''' (Branch Overflow Set) is a [[Super FX]] instruction that performs a branch when the overflow flag is set.
+'''BVS''' (Branch Overflow Set) is a [[Super FX]] instruction that performs a branch when the overflow flag ([[O/V]]) is set.  The instruction following BVS is already in the pipeline and will run even if the branch occurs.
+If the overflow flag is clear, control simply falls through and the branch does not happen.
 No flags are affected.
+==== Syntax ====
+<pre>
+BVS e
+</pre>
+==== Example ====
+Let the O/V flag be set.  This instruction jumps the program backward 2 bytes:
+<pre>
+ BVS $-2h
+</pre>
 === See Also ===