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GETBS (Super FX): Difference between revisions
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{| class="wikitable" style="float:right;clear:right;width:30%" | {| class="wikitable" style="float:right;clear:right;width:30%" | ||
!colspan="9"|Flags | !colspan="9"|Flags Affected | ||
|+ | |+ | ||
|B | |B | ||
|ALT1 | |[[ALT1]] | ||
|ALT2 | |[[ALT2]] | ||
|O/V | |[[O/V]] | ||
|S | |S | ||
|CY | |[[CY]] | ||
|Z | |Z | ||
|+ | |+ | ||
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|} | |} | ||
'''GETBS''' is a [[Super FX]] instruction that loads one byte from the ROM buffer. | '''GETBS''' is a [[Super FX]] instruction that loads one byte from the [[ROM buffer]] into the low byte of the [[destination register]]. Every bit of the high byte of the destination register becomes whatever bit 7 of that loaded byte is. | ||
The reason the cycle times can vary is because of the ROM buffer. | |||
=== See Also === | === See Also === | ||
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=== External Links === | === External Links === | ||
* Official Super Nintendo development manual on GETBS: [https://archive.org/details/SNESDevManual/book2/page/n211 Page 2-9-55 of Book II] | * Official Super Nintendo development manual on GETBS: [https://archive.org/details/SNESDevManual/book2/page/n211 Page 2-9-55 of Book II] | ||
* example: [https://archive.org/details/SNESDevManual/book2/page/n212 page 2-9-56 of Book II], lbid | |||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:Super FX]] | [[Category:Super FX]] | ||
[[Category:Data Transfer Instructions]] | [[Category:Data Transfer Instructions]] | ||
[[Category:Two-byte Instructions]] | |||
Latest revision as of 06:08, 29 November 2023
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Opcode | Length | ROM Speed | RAM Speed | Cache Speed | |||
| 3FEF | 2 bytes | 6 to 10 cycles | 6 to 9 cycles | 2 to 6 cycle | |||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| B | ALT1 | ALT2 | O/V | S | CY | Z | ||
| 0 | 0 | 0 | . | . | . | . | ||
GETBS is a Super FX instruction that loads one byte from the ROM buffer into the low byte of the destination register. Every bit of the high byte of the destination register becomes whatever bit 7 of that loaded byte is.
The reason the cycle times can vary is because of the ROM buffer.
See Also
External Links
- Official Super Nintendo development manual on GETBS: Page 2-9-55 of Book II
- example: page 2-9-56 of Book II, lbid