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BMI (Super FX): Difference between revisions

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{| class="wikitable" style="float:right;clear:right;width:40%"
{| class="wikitable" style="float:right;clear:right;width:50%"
!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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|[[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.
'''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.
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 ===
=== See Also ===
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=== External Links ===
=== External Links ===
* Official Nintendo documentation on BMI: [https://archive.org/details/SNESDevManual/book2/page/n182 Page 2-9-26 of Book II]
* 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.
* example: [https://archive.org/details/SNESDevManual/book2/page/n183 page 2-9-27], lbid.


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[[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