We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS

B Flag (Super FX): Difference between revisions

From SnesLab
Jump to: navigation, search
(subscripted)
m (Xetheria moved page B Flag to B Flag (Super FX): there is a b flag on the 6502 too)
 
(8 intermediate revisions by 2 users not shown)
Line 1: Line 1:
The '''B flag''' is on the [[Super FX]], and is set when [[WITH]] runs.
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:
Line 41: Line 48:
* [[GSU/LSR|LSR]]
* [[GSU/LSR|LSR]]
* [[MERGE]]
* [[MERGE]]
* [[MOVE]] Rn, Rn'
* [[MOVE]] R<sub>n</sub>, R<sub>n</sub>'
* [[MOVES]] Rn, Rn'
* [[MOVES]] R<sub>n</sub>, R<sub>n</sub>'
* [[MULT]] R<sub>n</sub>
* [[MULT]] R<sub>n</sub>
* [[MULT]] #n
* [[MULT]] #n
Line 66: Line 73:
* [[SUB]] #n
* [[SUB]] #n
* [[SWAP]]
* [[SWAP]]
* [[UMULT]] Rn
* [[UMULT]] R<sub>n</sub>
* and presumably UMULT #n too
* and presumably UMULT #n too


Line 74: Line 81:
* [[ALT1]]
* [[ALT1]]
* [[ALT2]]
* [[ALT2]]
* [[ALT0]]


=== Reference ===
=== 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:

See Also

References