Differences

This shows you the differences between two versions of the page.

--- vendor:yamaha:opl2 [2019/03/19 02:17] – [YM2413/VRC7] cr1901
+++ vendor:yamaha:opl2 [2019/12/30 18:27] (current) – clarify notes about ym2413 instrument rom source lord_nightmare
@@ Line 3: / Line 3: @@
 ======= Official Documentation: =======
-===== Datasheets ====
+===== Datasheets =====
   * The YM3812/OPL2 datasheet can be found [[http://map.grauw.nl/resources/sound/yamaha_ym3812_ds.pdf|here]].
   * The YM3526/OPL datasheet can be found [[http://map.grauw.nl/resources/sound/yamaha_ym3526.pdf|here]].
@@ Line 20: / Line 20: @@
   * Errata: Bit D5(0x20) 'OPL2 MODE' of the test register(0x01) in the YM3812/OPL2 datasheet is improperly explained on both the datasheet and in the application manual. When bit D5 (0x20) is CLEAR, writes to registers 0xE0-0xF5 are suppressed, but the operation of said registers continues with whatever value was last written to them. This means if you set TEST(0x01) bit D5, write non-zero values to registers 0xE0-0xF5, then clear TEST(0x01) bit D5, the wave generators will continue to use the values previously written to 0xE0-0xF5 even though the chip is technically in 'non OPL2' mode. To work around this, before switching the chip to 'non OPL2' mode, ensure the chip is in 'OPL2' mode by writing 0x20 to TEST(0x01), then write values of 0x00 to all registers from 0xE0-0xF5, and finally write 0x00 to TEST(0x01).
-====== YM2413/VRC7 ========
+======= Chip-specific Notes =======
-OPL Light/Light, aka OPLL, is a cost-reduced version of OPL2 that hardcodes 15 preset instruments and allows for 1 custom instrument to be created. The instrument ROM save silicon die space compared to registers. One nagging problem with OPLL is that up until recently, there was no known way to extract the instrument ROM contents. Thus, emulation of preset instruments was based on empirical approximations.
+===== YM2413/VRC7 =======
-==== YM2413 Instruments ====
+OPL Light/Light, aka OPLL, is a cost-reduced version of OPL2 that hard-codes 15 preset instruments and allows for 1 custom instrument to be created. The instrument ROM saves silicon die space compared to registers. One nagging problem with OPLL is that up until recently, there was no known way to extract the instrument ROM contents. Thus, emulation of preset instruments was based on empirical approximations.
-There is at present no die image of YM2413. In the near future, [[https://whitequark.org|whitequark]] will provide a die image suitable for RE. It is anticipated that the instruments ROM will be an implant ROM. This implies a delayering or staining to read out its contents.
+=== YM2413 D0/D1 debug state ===
+from Nuke.YKT's notes at https://pastebin.com/H5s4WQQ8 :
+<code>
+YM2413 test data output format(!!not verified on hardware!!).
+/CS = 0
+/WE = 1
+A0  = 0
+D0 and D1 serially output test data with internal clock rate
+Internal clock rate is MCLK/4
+Clock 0  1  2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17
+D0:   P8 P7 P6 P5 P4 P3 P2 P1 P0 E6 E5 E4 E2 E1 E0 0  0  0
+D1:   C8 C7 C6 C5 C4 C3 C2 C1 C0 0  0  0  0  0  0  0  0  0
+Px - Operator 0 phase generator output LSB bits
+Ex - Operator 17 envelope generator output
+Cx - Channel 6(?) output
+</code>
-==== VRC7 Debug Mode ====
-TODO
+=== YM2413 and VRC7 TEST register (0x0F) ===
+<code>
+TEST (0x0F)
+	76543210
+	|||||||\- if 1, Disables Car/Mod EG units, EG output is forced to 0 (max volume). This can be used as a crude DAC test, see below.
+	||||||\-- if 1, resets (and holds, while active) the Trem and Vib LFO counts to 0, and resets the rhythm LFSR to all 1s.
+	|||||\--- if 1, resets (and holds, while active) the PG count for Car/Mod at 0 (this effectively silences the chip)
+	||||\---- if 1, the EG unit clock comes from VRC7 'D2' Pin, and the Trem and Vib LFO clock dividers are disabled, so they increment once per clock (x64 and x1024 their usual clock rates, respectively)
+	|||\----- Does nothing?
+	||\------ Does nothing?
+	|\------- Does nothing?
+	\-------- Does nothing?
+</code>
+If bit 0 is set, this can be combined with setting bit 2, and writing the 'desired DAC' (really, offset in the SINE ROM) value to register 0x10+n (or any of the other frequency registers). Bit 2 will reset the phase generator offset to 0 every tick, which combined with 0x10 to set the frequency LSB (which is added to the phase generator offset), can be used to crudely force the DAC to any specific value in the sine wave. Setting the frequency MSB (0x20+n) should also similarly affect this. The Volume and instrument settings in (0x30+n) still take effect, as do carrier/modulator effects, so keep this in mind.
+=== VRC7 Debug Mode ===
+TODO (see https://pastebin.com/2gAwGmFT )
+<nukeykt> VRC7 D0-D7 are bidirectional. Internally data bus connected to 8-bit multiplexer and with right combination of chip's pins it's possible to configure it. Internal instrument bus connected to this multiplexer, so it's possible to dump it
+<nukeykt> For all configs A13(pin 2)=1, M2(pin 47)=0, P15=0, [...] For config 0: /CS=1, /WR=1, A0=1, for config 1: /CS=1, /WR=1, A0=0, etc.
+==== YM2413 Instrument ROM ====
+These values were initially created using hardware tests by nukeykt, but later were corrected by crosschecking data with the visible bits on the fhb013 (presumably ym2413b) die shot, located at [[https://siliconpr0n.org/archive/doku.php?id=digshadow:yamaha:fhb013]] .
+<code>
+/* Order of array = { modulator, carrier } */
+typedef struct {
+    Bit8u tl;
+    Bit8u dc;
+    Bit8u dm;
+    Bit8u fb;
+    Bit8u am[2];
+    Bit8u vib[2];
+    Bit8u et[2];
+    Bit8u ksr[2];
+    Bit8u multi[2];
+    Bit8u ksl[2];
+    Bit8u ar[2];
+    Bit8u dr[2];
+    Bit8u sl[2];
+    Bit8u rr[2];
+} opll_patch_t;
+static const opll_patch_t patch_ym2413[opll_patch_max] = {
+    { 0x1e, 0x01, 0x00, 0x07,{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x01 },{ 0x01, 0x00 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x0d, 0x07 },{ 0x00, 0x08 },{ 0x00, 0x01 },{ 0x00, 0x07 } },
+    { 0x1a, 0x00, 0x01, 0x05,{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x03, 0x01 },{ 0x00, 0x00 },{ 0x0d, 0x0f },{ 0x08, 0x07 },{ 0x02, 0x01 },{ 0x03, 0x03 } },
+    { 0x19, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x03, 0x01 },{ 0x02, 0x00 },{ 0x0f, 0x0c },{ 0x02, 0x04 },{ 0x01, 0x02 },{ 0x01, 0x03 } },
+    { 0x0e, 0x00, 0x00, 0x07,{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x01, 0x01 },{ 0x01, 0x00 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x0a, 0x06 },{ 0x08, 0x04 },{ 0x07, 0x02 },{ 0x00, 0x07 } },
+    { 0x1e, 0x00, 0x00, 0x06,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x00 },{ 0x02, 0x01 },{ 0x00, 0x00 },{ 0x0e, 0x07 },{ 0x00, 0x06 },{ 0x00, 0x02 },{ 0x00, 0x08 } },
+    { 0x16, 0x00, 0x00, 0x05,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x00 },{ 0x01, 0x02 },{ 0x00, 0x00 },{ 0x0e, 0x07 },{ 0x00, 0x01 },{ 0x00, 0x01 },{ 0x00, 0x08 } },
+    { 0x1d, 0x00, 0x00, 0x07,{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x08, 0x08 },{ 0x02, 0x01 },{ 0x01, 0x00 },{ 0x00, 0x07 } },
+    { 0x2d, 0x01, 0x00, 0x04,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x03, 0x01 },{ 0x00, 0x00 },{ 0x0a, 0x07 },{ 0x02, 0x02 },{ 0x00, 0x00 },{ 0x00, 0x07 } },
+    { 0x1b, 0x00, 0x00, 0x06,{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x06, 0x06 },{ 0x04, 0x05 },{ 0x01, 0x01 },{ 0x00, 0x07 } },
+    { 0x0b, 0x01, 0x01, 0x00,{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x08, 0x0f },{ 0x05, 0x07 },{ 0x07, 0x00 },{ 0x01, 0x07 } },
+    { 0x03, 0x01, 0x00, 0x01,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x03, 0x01 },{ 0x02, 0x00 },{ 0x0f, 0x0e },{ 0x0a, 0x04 },{ 0x01, 0x00 },{ 0x00, 0x04 } },
+    { 0x24, 0x00, 0x00, 0x07,{ 0x00, 0x01 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x07, 0x01 },{ 0x00, 0x00 },{ 0x0f, 0x0f },{ 0x08, 0x08 },{ 0x02, 0x01 },{ 0x02, 0x02 } },
+    { 0x0c, 0x00, 0x00, 0x05,{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x00 },{ 0x00, 0x01 },{ 0x01, 0x00 },{ 0x00, 0x00 },{ 0x0c, 0x0f },{ 0x02, 0x05 },{ 0x02, 0x04 },{ 0x00, 0x02 } },
+    { 0x15, 0x00, 0x00, 0x03,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x00 },{ 0x0c, 0x09 },{ 0x09, 0x05 },{ 0x00, 0x00 },{ 0x03, 0x02 } },
+    { 0x09, 0x00, 0x00, 0x03,{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x02, 0x00 },{ 0x0f, 0x0e },{ 0x01, 0x04 },{ 0x04, 0x01 },{ 0x00, 0x03 } },
+    { 0x18, 0x00, 0x01, 0x07,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x00, 0x00 },{ 0x0d, 0x00 },{ 0x0f, 0x00 },{ 0x06, 0x00 },{ 0x0a, 0x00 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x00, 0x00 },{ 0x0c, 0x00 },{ 0x08, 0x00 },{ 0x0a, 0x00 },{ 0x07, 0x00 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x05, 0x00 },{ 0x00, 0x00 },{ 0x0f, 0x00 },{ 0x08, 0x00 },{ 0x05, 0x00 },{ 0x09, 0x00 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x00, 0x0f },{ 0x00, 0x08 },{ 0x00, 0x06 },{ 0x00, 0x0d } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x00, 0x0d },{ 0x00, 0x08 },{ 0x00, 0x04 },{ 0x00, 0x08 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x00, 0x0a },{ 0x00, 0x0a },{ 0x00, 0x05 },{ 0x00, 0x05 } }
+};
+</code>
+This translates into a patchset of:
+<code>
+: user patch (irrelevant)
+: $71 $61 $1E $17 $D0 $78 $00 $17
+: $13 $41 $1A $0D $D8 $F7 $23 $13
+: $13 $01 $99 $00 $F2 $C4 $11 $23
+: $31 $61 $0E $07 $A8 $64 $70 $27
+: $32 $21 $1E $06 $E0 $76 $00 $28
+: $31 $22 $16 $05 $E0 $71 $00 $18
+: $21 $61 $1D $07 $82 $81 $10 $07
+: $23 $21 $2D $14 $A2 $72 $00 $07
+: $61 $61 $1B $06 $64 $65 $10 $17
+A: $41 $61 $0B $18 $85 $F7 $71 $07
+B: $13 $01 $83 $11 $FA $E4 $10 $04
+C: $17 $C1 $24 $07 $F8 $F8 $22 $12
+D: $61 $50 $0C $05 $C2 $F5 $20 $42
+E: $01 $01 $55 $03 $C9 $95 $03 $02
+F: $61 $41 $89 $03 $F1 $E4 $40 $13
+Drums
+BD   : $01 $01 $18 $0F $DF $F8 $6A $6D
+SD/HH: $01 $01 $00 $00 $C8 $D8 $A7 $48
+TM/TC: $05 $01 $00 $00 $F8 $AA $59 $55
+</code>
 ==== VRC7 Instrument ROM Dump ====
-Fellow Yamaha enthusiast [[https://nukeykt.retrohost.net|NukeYKT]] [[https://freenode.irclog.whitequark.org/~h~yamahasynths/2019-03-15#24228789;|dumped]] the instrument table using the aforementioned debug mode. The table is reproduced here (Rhythm instruments have not been dumped yet):
+Fellow Yamaha enthusiast [[https://nukeykt.retrohost.net|NukeYKT]] [[https://freenode.irclog.whitequark.org/~h~yamahasynths/2019-03-15#24228789;|dumped]] the instrument and rhythm tables using the aforementioned debug mode. The tables are reproduced here:
 <code>
 /* Order of array = { modulator, carrier } */
@@ Line 65: / Line 174: @@
     { 0x0c, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x01, 0x01 },{ 0x01, 0x01 },{ 0x00, 0x00 },{ 0x01, 0x03 },{ 0x00, 0x00 },{ 0x09, 0x0c },{ 0x04, 0x00 },{ 0x03, 0x0f },{ 0x03, 0x06 } },
     { 0x0d, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x01, 0x01 },{ 0x00, 0x01 },{ 0x01, 0x02 },{ 0x00, 0x00 },{ 0x0c, 0x0d },{ 0x01, 0x05 },{ 0x05, 0x00 },{ 0x06, 0x06 } },
-    /* TODO */
+    /* Rhythm Patches: rows 1 and 4 are bass drum, 2 and 5 are Snare Drum & Hi-Hat, 3 and 6 are Tom and Top Cymbal */
-    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 } },
+    { 0x18, 0x00, 0x01, 0x07,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x00, 0x00 },{ 0x0d, 0x00 },{ 0x0f, 0x00 },{ 0x06, 0x00 },{ 0x0a, 0x00 } },
-    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x01, 0x00 },{ 0x00, 0x00 },{ 0x0c, 0x00 },{ 0x08, 0x00 },{ 0x0a, 0x00 },{ 0x07, 0x00 } },
-    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x05, 0x00 },{ 0x00, 0x00 },{ 0x0f, 0x00 },{ 0x08, 0x00 },{ 0x05, 0x00 },{ 0x09, 0x00 } },
-    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x00, 0x0f },{ 0x00, 0x08 },{ 0x00, 0x06 },{ 0x00, 0x0d } },
-    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 } },
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x00, 0x0d },{ 0x00, 0x08 },{ 0x00, 0x06 },{ 0x00, 0x08 } },
-    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 } }
+    { 0x00, 0x00, 0x00, 0x00,{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x00 },{ 0x00, 0x01 },{ 0x00, 0x00 },{ 0x00, 0x0a },{ 0x00, 0x0a },{ 0x00, 0x05 },{ 0x00, 0x05 } }
 };
 </code>
+This translates into a patchset of:
+<code>
+: user patch (irrelevant)
+: $03 $21 $05 $06 $E8 $81 $42 $27
+: $13 $41 $14 $0D $D8 $F6 $23 $12
+: $11 $11 $08 $08 $FA $B2 $20 $12
+: $31 $61 $0C $07 $A8 $64 $61 $27
+: $32 $21 $1E $06 $E1 $76 $01 $28
+: $02 $01 $06 $00 $A3 $E2 $F4 $F4
+: $21 $61 $1D $07 $82 $81 $11 $07
+: $23 $21 $22 $17 $A2 $72 $01 $17
+: $35 $11 $25 $00 $40 $73 $72 $01
+A: $B5 $01 $0F $0F $A8 $A5 $51 $02
+B: $17 $C1 $24 $07 $F8 $F8 $22 $12
+C: $71 $23 $11 $06 $65 $74 $18 $16
+D: $01 $02 $D3 $05 $C9 $95 $03 $02
+E: $61 $63 $0C $00 $94 $C0 $33 $F6
+F: $21 $72 $0D $00 $C1 $D5 $56 $06
+Drums (silent due to no RO output pin(?) on VRC7, but present internally; these are likely shared with YM2413)
+BD   : $01 $01 $18 $0F $DF $F8 $6A $6D
+SD/HH: $01 $01 $00 $00 $C8 $D8 $A7 $68
+TM/TC: $05 $01 $00 $00 $F8 $AA $59 $55
+</code>
+==== OPLL/VRC7 Patch Format ====
+<code>
+byte 0:
+	76543210
+	||||\\\\- MULT (Mod)
+	|||\----- Key Scale Rate enable (Mod)
+	||\------ Env Gen Type (0 = percussion/auto-key-off, 1 = sustain/normal) (Mod)
+	|\------- Vibrato enable (Mod)
+	\-------- Tremolo enable (Mod)
+byte 1:
+	76543210
+	||||\\\\- MULT (Car)
+	|||\----- Key Scale Rate enable (Car)
+	||\------ Env Gen Type (0 = percussion/auto-key-off, 1 = sustain/normal) (Car)
+	|\------- Vibrato enable (Car)
+	\-------- Tremolo enable (Car)
+byte 2:
+	76543210
+	||\\\\\\- Total Level, inverted (Mod)
+	\\------- Key Scale Level (Mod)
+byte 3:
+	76543210
+	|||||\\\- Feedback level (Mod)
+	||||\---- WF select (sine vs halfsine, Mod)
+	|||\----- WF select (sine vs halfsine, Car)
+	||\------ Unused
+	\\------- Key Scale Level (Car)
+byte 4:
+	76543210
+	||||\\\\- Decay Rate, inverted (Mod)
+	\\\\----- Attack Rate, inverted (Mod)
+byte 5:
+	76543210
+	||||\\\\- Decay Rate, inverted (Car)
+	\\\\----- Attack Rate, inverted (Car)
+byte 6:
+	76543210
+	||||\\\\- Release Rate, inverted (Mod)
+	\\\\----- Sustain Level, inverted (Mod)
+byte 7:
+	76543210
+	||||\\\\- Release Rate, inverted (Car)
+	\\\\----- Sustain Level, inverted (Car)
+</code>