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BLT (Super FX): Difference between revisions
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!colspan="8"|Basic Info | |||
|+ | |||
|'''Addressing Mode''' | |||
|'''Opcode''' | |||
|'''Length''' | |||
|'''ROM Speed''' | |||
|'''RAM Speed''' | |||
|'''Cache Speed''' | |||
|+ | |||
|[[Program Counter Relative]] | |||
|06 | |||
|2 bytes | |||
|6 cycles | |||
|6 cycles | |||
|2 cycles | |||
|} | |||
{| class="wikitable" style="float:right;clear:right;width:30%" | |||
!colspan="9"|Flags Affected | |||
|+ | |||
|[[B Flag|B]] | |||
|[[ALT1]] | |||
|[[ALT2]] | |||
|[[O/V]] | |||
|[[Sign Flag|S]] | |||
|[[CY]] | |||
|[[Zero Flag|Z]] | |||
|+ | |||
|. | |||
|. | |||
|. | |||
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'''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> | |||
No flags are affected. | |||
==== Syntax ==== | |||
<pre> | |||
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> | |||
=== See also === | |||
* [[BGE]] | |||
* [[BCC (Super FX)]] | |||
=== External Links === | |||
# Official Nintendo documentation on BLT: [https://archive.org/details/SNESDevManual/book2/page/n180 Page 2-9-24 of Book II] | |||
# https://problemkaputt.de/fullsnes.htm#snescartgsuncpumisc | |||
# example: [https://archive.org/details/SNESDevManual/book2/page/n181 page 2-9-25], lbid. | |||
[[Category:ASM]] | |||
[[Category:Super FX]] | |||
[[Category:GSU Control Instructions]] | |||
[[Category:Instructions with Delay Slots]] | |||
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.