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BMI (Super FX): Difference between revisions
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!colspan="8"|Basic Info | !colspan="8"|Basic Info | ||
|+ | |+ | ||
|'''Addressing Mode''' | |||
|'''Opcode''' | |'''Opcode''' | ||
|'''Length''' | |'''Length''' | ||
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|'''Cache Speed''' | |'''Cache Speed''' | ||
|+ | |+ | ||
|[[Program Counter Relative]] | |||
|0B?? | |0B?? | ||
|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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|. | |. | ||
|} | |} | ||
'''BMI''' (Branch Minus) is a [[Super FX]] instruction that performs a conditional jump if the [[sign flag]] is set. If the sign flag is clear, control simply falls through. The instruction after BMI is already in the pipeline and will run even if the branch occurs. | |||
No flags are affected. | |||
==== Syntax ==== | |||
<pre> | |||
BMI e | |||
</pre> | |||
where e can be from -128 to 127. | |||
==== Example ==== | |||
Let the sign flag be set. This instruction jumps the program forward 5 bytes: | |||
<pre> | |||
BMI $+5h | |||
</pre> | |||
=== See Also === | |||
* [[BPL (Super FX)]] | |||
* [[BMI]] | |||
=== External Links === | === External Links === | ||
* Official Nintendo documentation on BMI: https://archive.org/details/SNESDevManual/book2/page/n182 | * Official Nintendo documentation on BMI: paragraph 9.21 on [https://archive.org/details/SNESDevManual/book2/page/n182 page 2-9-26 of Book II] | ||
* example: [https://archive.org/details/SNESDevManual/book2/page/n183 page 2-9-27], lbid. | |||
[[Category:Super FX]] | [[Category:Super FX]] | ||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:Instructions with Delay Slots]] |
Latest revision as of 08:34, 14 July 2024
Basic Info | |||||||
---|---|---|---|---|---|---|---|
Addressing Mode | Opcode | Length | ROM Speed | RAM Speed | Cache Speed | ||
Program Counter Relative | 0B?? | 2 bytes | 6 cycles | 6 cycles | 2 cycles |
Flags Affected | ||||||||
---|---|---|---|---|---|---|---|---|
B | ALT1 | ALT2 | O/V | S | CY | Z | ||
. | . | . | . | . | . | . |
BMI (Branch Minus) is a Super FX instruction that performs a conditional jump if the sign flag is set. If the sign flag is clear, control simply falls through. The instruction after BMI is already in the pipeline and will run even if the branch occurs.
No flags are affected.
Syntax
BMI e
where e can be from -128 to 127.
Example
Let the sign flag be set. This instruction jumps the program forward 5 bytes:
BMI $+5h
See Also
External Links
- Official Nintendo documentation on BMI: paragraph 9.21 on page 2-9-26 of Book II
- example: page 2-9-27, lbid.