Table of Gain Modes: Difference between revisions

Revision as of 19:57, 21 June 2023

The S-DSP has five gain modes, to which Nintendo gave official names [1], but they are numbered differently by different emulator authors.

nocash numbers the gain modes with bits 5 & 6 of VxGAIN. [2] Note that direct gain mode uses these bits for the fixed volume instead and thus has no number in this scheme.

Near numbers the gain modes with the top 3 bits of ADSR(1).[3] Note that when bit 7 is clear, bits 5 & 6 are "don't care" and thus Modes 0-3 are actually all the same - direct gain.


Official Nintendo Name	nocash numbering/naming	Near numbering/naming
Direct Designation	Direct Gain	Modes 0-3 (direct)
Increase Mode (Linear)	Mode 2 = Linear Increase	Mode 6 (linear increase)
Increase Mode (Bent Line)	Mode 3 = Bent Increase	Mode 7 (two-slope linear increase)
Decrease Mode (Linear)	Mode 0 = Linear Decrease	Mode 4 (linear decrease)
Decrease Mode (Exponential)	Mode 1 = Exp Decrease	Mode 5 (exponential decrease)

References

[1] page 3-7-4, "GAIN" of the official Super Nintendo development manual: https://archive.org/details/SNESDevManual/book1/page/n170
[2] https://problemkaputt.de/fullsnes.htm#snesapudspadsrgainenvelope
[3] https://github.com/ares-emulator/ares/blob/master/ares/sfc/dsp/envelope.cpp

@@ Line 5: / Line 5: @@
 [[Near]] numbers the gain modes with the top 3 bits of ADSR(1).[3] Note that when bit 7 is clear, bits 5 & 6 are "don't care" and thus Modes 0-3 are actually all the same - direct gain.
-<pre>
+{| class="wikitable"
-| Official Nintendo Name	| nocash numbering/naming	| Near numbering/naming
+|+
-|-------------------------------+-------------------------------|----------------------------------
+! Official Nintendo Name	!! nocash numbering/naming	!! Near numbering/naming
-| Direct Designation		|	   Direct Gain		| Modes 0-3 (direct)
+|+
-| Increase Mode (Linear)	| Mode 2 = Linear Increase	| Mode 6    (linear increase)
+| '''Direct Designation'''        ||	   Direct Gain		|| Modes 0-3 (direct)
-| Increase Mode (Bent Line)	| Mode 3 = Bent Increase	| Mode 7    (two-slope linear increase)
+|+
-| Decrease Mode (Linear)	| Mode 0 = Linear Decrease	| Mode 4    (linear decrease)
+| '''Increase Mode (Linear)'''	|| Mode 2 = Linear Increase	|| Mode 6    (linear increase)
-| Decrease Mode (Exponential)	| Mode 1 = Exp Decrease		| Mode 5    (exponential decrease)
+|+
-</pre>
+| '''Increase Mode (Bent Line)'''	|| Mode 3 = Bent Increase	|| Mode 7    (two-slope linear increase)
+|+
+| '''Decrease Mode (Linear)'''	|| Mode 0 = Linear Decrease	|| Mode 4    (linear decrease)
+|+
+| '''Decrease Mode (Exponential)'''	|| Mode 1 = Exp Decrease	|| Mode 5    (exponential decrease)
+|}
 === References ===