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BLT (Super FX): Difference between revisions
From SnesLab
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{| class="wikitable" style="float:right;clear:right;width: | {| class="wikitable" style="float:right;clear:right;width:50%" | ||
!colspan="8"|Basic Info | !colspan="8"|Basic Info | ||
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|'''Cache Speed''' | |'''Cache Speed''' | ||
|+ | |+ | ||
| | |[[Program Counter Relative]] | ||
|06 | |06 | ||
|2 bytes | |2 bytes | ||
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|[[Sign Flag|S]] | |[[Sign Flag|S]] | ||
|[[CY]] | |[[CY]] | ||
|Z | |[[Zero Flag|Z]] | ||
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'''BLT''' (Branch if Less Than) is a [[Super FX]] opcode that performs a jump if the [[ | '''BLT''' (Branch if Less Than) is a [[Super FX]] opcode that performs a jump if the [[sign flag]] is unequal to the [[O/V]] flag, effectively checking for a signed less-than comparison (compare [[BCC]] which is an unsigned less-than comparison). | ||
According to [[fullsnes]], the official documentation has BLT exchanged with [[BGE]]. <sup>[2]</sup> | According to [[fullsnes]], the official documentation has BLT exchanged with [[BGE]]. <sup>[2]</sup> | ||
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<pre> | <pre> | ||
BLT e | BLT e | ||
</pre> | |||
==== Example ==== | |||
Let the sign flag be set and the overflow flag clear. This instruction jumps the program forward 4 bytes: | |||
<pre> | |||
BLT $+4h | |||
</pre> | </pre> | ||
Latest revision as of 19:16, 4 August 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | ROM Speed | RAM Speed | Cache Speed | ||
| Program Counter Relative | 06 | 2 bytes | 6 cycles | 6 cycles | 2 cycles | ||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| B | ALT1 | ALT2 | O/V | S | CY | Z | ||
| . | . | . | . | . | . | . | ||
BLT (Branch if Less Than) is a Super FX opcode that performs a jump if the sign flag is unequal to the O/V flag, effectively checking for a signed less-than comparison (compare BCC which is an unsigned less-than comparison).
According to fullsnes, the official documentation has BLT exchanged with BGE. [2]
No flags are affected.
Syntax
BLT e
Example
Let the sign flag be set and the overflow flag clear. This instruction jumps the program forward 4 bytes:
BLT $+4h
See also
External Links
- Official Nintendo documentation on BLT: Page 2-9-24 of Book II
- https://problemkaputt.de/fullsnes.htm#snescartgsuncpumisc
- example: page 2-9-25, lbid.