BVS: Difference between revisions

Latest revision as of 03:21, 6 December 2023


Basic Info
Addressing Mode	Opcode	Length	Speed
Program Counter Relative	70	2 bytes	2 cycles*


Flags Affected
N	V	M	X	D	I	Z	C
.	.	.	.	.	.	.	.

BVS is a 65x instruction that performs a branch if the overflow flag is set.

Cycle Penalties

BVS takes one extra cycle if the branch is taken
BVS takes another extra cycle if that branch taken crosses a page boundary in emulation mode.

External Links

Eyes & Lichty page 440 on BVS: https://archive.org/details/0893037893ProgrammingThe65816/page/n466
Labiak page 129 on BVS: https://archive.org/details/Programming_the_65816/page/n139
MCS6500 Manual page 41 on BVS: https://archive.org/details/mos_microcomputers_programming_manual/page/n56
Carr page 253 on BVS: https://archive.org/details/6502UsersManual/page/n266
Leventhal page 3-51 on BVS: https://archive.org/details/6502-assembly-language-programming/page/n100
snes9x implementation of BVS: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1400

@@ Line 1: / Line 1: @@
-'''BVS''' is a 65x instruction that performs a branch if the [[overflow flag]] is set.
+{| class="wikitable" style="float:right;clear:right;width:40%"
+!colspan="8"|Basic Info
+|+
+|'''Addressing Mode'''
+|'''Opcode'''
+|'''Length'''
+|'''Speed'''
+|+
+|[[Program Counter Relative]]
+|70
+|2 bytes
+|2 cycles*
+|}
 {| class="wikitable" style="float:right;clear:right;width:30%"
-!colspan="9"|Flags Clobbered
+!colspan="9"|Flags Affected
 |+
-|N
+|[[Negative Flag|N]]
-|V
+|[[Overflow Flag|V]]
-|M
+|[[M Flag|M]]
-|X
+|[[X Flag|X]]
-|D
+|[[Decimal Flag|D]]
-|I
+|[[I Flag|I]]
-|Z
+|[[Zero Flag|Z]]
-|C
+|[[Carry Flag|C]]
 |+
 |.
@@ Line 22: / Line 34: @@
 |.
 |}
+'''BVS''' is a 65x instruction that performs a branch if the [[overflow flag]] is set.
+===== Cycle Penalties =====
+* BVS takes one extra cycle if the branch is taken
+* BVS takes another extra cycle if that branch taken crosses a page boundary in [[emulation mode]].
+=== See Also ===
+* [[BVC]]
+* [[BVS (SPC700)]]
 === External Links ===
-* [[Eyes & Lichty]] page on BVS: https://archive.org/details/0893037893ProgrammingThe65816/page/n465
+* [[Eyes & Lichty]] page 440 on BVS: https://archive.org/details/0893037893ProgrammingThe65816/page/n466
+* [[Labiak]] page 129 on BVS: https://archive.org/details/Programming_the_65816/page/n139
+* [[MCS6500 Manual]] page 41 on BVS: https://archive.org/details/mos_microcomputers_programming_manual/page/n56
+* [[Carr]] page 253 on BVS: https://archive.org/details/6502UsersManual/page/n266
+* [[Leventhal]] page 3-51 on BVS: https://archive.org/details/6502-assembly-language-programming/page/n100
+* snes9x implementation of BVS: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1400
 [[Category:ASM]]
 [[Category:Inherited from 6502]]
+[[Category:Conditional Branches]]
+[[Category:Two-byte Instructions]]