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B Flag (Super FX): Difference between revisions
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The '''B | The '''B Flag''' is on the [[Super FX]], and is set when [[WITH]] runs. It is bit 4 of SFR. | ||
These instructions change their behaviour on the B flag: | |||
* [[TO]] R<sub>n'</sub> as [[MOVE]] R<sub>n</sub>,R<sub>n'</sub> | |||
* [[FROM]] R<sub>n'</sub> as [[MOVES]] R<sub>n</sub>,R<sub>n'</sub> | |||
For both of them, the R<sub>n</sub> is set by the preceeeding WITH R<sub>n</sub>. | |||
Many instructions clear the B flag, including: | Many instructions clear the B flag, including: | ||
* ADC R<sub>n</sub> | * [[GSU/ADC|ADC]] R<sub>n</sub> | ||
* ADC #n | * [[GSU/ADC|ADC]] #n | ||
* [[ADD]] R<sub>n</sub> | * [[ADD]] R<sub>n</sub> | ||
* [[ADD]] #n | * [[ADD]] #n | ||
* AND R<sub>n</sub> | * [[GSU/AND|AND]] R<sub>n</sub> | ||
* AND #n | * [[GSU/AND|AND]] #n | ||
* ASR | * [[ASR]] | ||
* [[BIC]] R<sub>n</sub> | * [[BIC]] R<sub>n</sub> | ||
* [[BIC]] #n | * [[BIC]] #n | ||
* [[CACHE]] | * [[CACHE]] | ||
* [[CMODE]] | * [[CMODE]] | ||
* CMP R<sub>n</sub> | * [[GSU/CMP|CMP]] R<sub>n</sub> | ||
* [[COLOR]] | * [[COLOR]] | ||
* DEC R<sub>n</sub> | * [[GSU/DEC|DEC]] R<sub>n</sub> | ||
* [[DIV2]] | * [[DIV2]] | ||
* [[FMULT]] | * [[FMULT]] | ||
| Line 25: | Line 32: | ||
* [[GETC]] | * [[GETC]] | ||
* [[HIB]] | * [[HIB]] | ||
* [[IBT]] | * [[IBT]] R<sub>n</sub>, #pp | ||
* INC | * [[GSU/INC|INC]] R<sub>n</sub> | ||
* [[IWT]] | * [[IWT]] R<sub>n</sub>, #xx | ||
* JMP R<sub>n</sub> | * [[GSU/JMP|JMP]] R<sub>n</sub> | ||
* [[LDB]] ( | * [[LDB]] (R<sub>m</sub>) | ||
* [[LDW]] ( | * [[LDW]] (R<sub>m</sub>) | ||
* [[LEA]] | * [[LEA]] R<sub>n</sub>, xx | ||
* [[LINK]] #n | * [[LINK]] #n | ||
* [[LJMP]] R<sub>n</sub> | * [[LJMP]] R<sub>n</sub> | ||
* LM | * [[LM]] R<sub>n</sub>, (xx) | ||
* [[LMS]] | * [[LMS]] R<sub>n</sub>, (yy) | ||
* [[LMULT]] | * [[LMULT]] | ||
* [[LOB]] | * [[LOB]] | ||
* [[LOOP]] | * [[LOOP]] | ||
* LSR | * [[GSU/LSR|LSR]] | ||
* [[MERGE]] | * [[MERGE]] | ||
* [[MOVE]] | * [[MOVE]] R<sub>n</sub>, R<sub>n</sub>' | ||
* [[MOVES]] | * [[MOVES]] R<sub>n</sub>, R<sub>n</sub>' | ||
* [[MULT]] | * [[MULT]] R<sub>n</sub> | ||
* [[MULT]] #n | * [[MULT]] #n | ||
* NOP | * [[GSU/NOP|NOP]] | ||
* [[NOT]] | * [[NOT]] | ||
* [[OR]] | * [[OR]] R<sub>n</sub> | ||
* [[OR]] #n | * [[OR]] #n | ||
* [[PLOT]] | * [[PLOT]] | ||
* [[RAMB]] | * [[RAMB]] | ||
* ROL | * [[GSU/ROL|ROL]] | ||
* [[ROMB]] | * [[ROMB]] | ||
* ROR | * [[GSU/ROR|ROR]] | ||
* [[RPIX]] | * [[RPIX]] | ||
* SBC | * [[GSU/SBC|SBC]] R<sub>n</sub> | ||
* [[SBK]] | * [[SBK]] | ||
* [[SEX]] | * [[SEX]] | ||
* [[SM]] (xx), | * [[SM]] (xx), R<sub>n</sub> | ||
* [[SMS]] (yy), | * [[SMS]] (yy), R<sub>n</sub> | ||
* [[STB]] ( | * [[STB]] (R<sub>m</sub>) | ||
* [[STOP]] | * [[STOP]] | ||
* [[STW]] ( | * [[STW]] (R<sub>m</sub>) | ||
* [[SUB]] | * [[SUB]] R<sub>n</sub> | ||
* [[SUB]] #n | * [[SUB]] #n | ||
* [[SWAP]] | * [[SWAP]] | ||
* [[UMULT]] | * [[UMULT]] R<sub>n</sub> | ||
* and presumably UMULT #n too | * and presumably UMULT #n too | ||
| Line 74: | Line 81: | ||
* [[ALT1]] | * [[ALT1]] | ||
* [[ALT2]] | * [[ALT2]] | ||
* [[ALT0]] | |||
=== | === References === | ||
* [https://archive.org/details/SNESDevManual/book2/page/n158 page 2-9-2 of Book II] of the official Super Nintendo development manual | * [https://archive.org/details/SNESDevManual/book2/page/n158 page 2-9-2 of Book II] of the official Super Nintendo development manual | ||
* [https://archive.org/details/SNESDevManual/book2/page/n110 page 2-4-4 of Book II], lbid. | |||
[[Category:Flags]] | [[Category:Flags]] | ||
[[Category:Super FX]] | [[Category:Super FX]] | ||
[[Category:ASM]] | [[Category:ASM]] | ||
Latest revision as of 23:06, 21 July 2024
The B Flag is on the Super FX, and is set when WITH runs. It is bit 4 of SFR.
These instructions change their behaviour on the B flag:
For both of them, the Rn is set by the preceeeding WITH Rn.
Many instructions clear the B flag, including:
- ADC Rn
- ADC #n
- ADD Rn
- ADD #n
- AND Rn
- AND #n
- ASR
- BIC Rn
- BIC #n
- CACHE
- CMODE
- CMP Rn
- COLOR
- DEC Rn
- DIV2
- FMULT
- GETB
- GETBH
- GETBL
- GETBS
- GETC
- HIB
- IBT Rn, #pp
- INC Rn
- IWT Rn, #xx
- JMP Rn
- LDB (Rm)
- LDW (Rm)
- LEA Rn, xx
- LINK #n
- LJMP Rn
- LM Rn, (xx)
- LMS Rn, (yy)
- LMULT
- LOB
- LOOP
- LSR
- MERGE
- MOVE Rn, Rn'
- MOVES Rn, Rn'
- MULT Rn
- MULT #n
- NOP
- NOT
- OR Rn
- OR #n
- PLOT
- RAMB
- ROL
- ROMB
- ROR
- RPIX
- SBC Rn
- SBK
- SEX
- SM (xx), Rn
- SMS (yy), Rn
- STB (Rm)
- STOP
- STW (Rm)
- SUB Rn
- SUB #n
- SWAP
- UMULT Rn
- and presumably UMULT #n too
See Also
References
- page 2-9-2 of Book II of the official Super Nintendo development manual
- page 2-4-4 of Book II, lbid.