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BGE (Super FX): Difference between revisions
From SnesLab
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!colspan="8"|Basic Info | !colspan="8"|Basic Info | ||
|+ | |+ | ||
|'''Addressing Mode''' | |||
|'''Opcode''' | |'''Opcode''' | ||
|'''Length''' | |'''Length''' | ||
| Line 8: | Line 9: | ||
|'''Cache Speed''' | |'''Cache Speed''' | ||
|+ | |+ | ||
|[[Program Counter Relative]] | |||
|07 | |07 | ||
|2 bytes | |2 bytes | ||
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!colspan="9"|Flags Affected | !colspan="9"|Flags Affected | ||
|+ | |+ | ||
|B | |[[B Flag|B]] | ||
|[[ALT1]] | |[[ALT1]] | ||
|[[ALT2]] | |[[ALT2]] | ||
|[[O/V]] | |[[O/V]] | ||
|S | |[[Sign Flag|S]] | ||
|[[CY]] | |[[CY]] | ||
|Z | |[[Zero Flag|Z]] | ||
|+ | |+ | ||
|. | |. | ||
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|} | |} | ||
'''BGE''' (Branch if Greater or Equal) is a [[Super FX]] opcode that performs a jump if the [[ | '''BGE''' (Branch if Greater or Equal) is a [[Super FX]] opcode that performs a jump if the [[sign flag]] is equal to the [[O/V]] flag, effectively checking for a signed greater-equal comparison (compare [[BCS]] which is an unsigned greater-equal comparison). | ||
According to [[fullsnes]], the official documentation has BGE exchanged with [[BLT]]. <sup>[2]</sup> | According to [[fullsnes]], the official documentation has BGE exchanged with [[BLT]]. <sup>[2]</sup> | ||
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<pre> | <pre> | ||
BGE e | BGE e | ||
</pre> | |||
==== Example ==== | |||
Let the sign flag and O/V flag be set. This instruction jumps the program backward 3 bytes: | |||
<pre> | |||
BGE $-3h | |||
</pre> | </pre> | ||
Latest revision as of 19:17, 4 August 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | ROM Speed | RAM Speed | Cache Speed | ||
| Program Counter Relative | 07 | 2 bytes | 6 cycles | 6 cycles | 2 cycles | ||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| B | ALT1 | ALT2 | O/V | S | CY | Z | ||
| . | . | . | . | . | . | . | ||
BGE (Branch if Greater or Equal) is a Super FX opcode that performs a jump if the sign flag is equal to the O/V flag, effectively checking for a signed greater-equal comparison (compare BCS which is an unsigned greater-equal comparison).
According to fullsnes, the official documentation has BGE exchanged with BLT. [2]
No flags are affected.
Syntax
BGE e
Example
Let the sign flag and O/V flag be set. This instruction jumps the program backward 3 bytes:
BGE $-3h
See also
References
- Official Nintendo dev manual on BGE: 9.17 on page 2-9-20 of Book II
- https://problemkaputt.de/fullsnes.htm#snescartgsuncpumisc
- example: page 2-9-21, lbid.