Merge branch 'master' into preset2

2022-03-28 12:46:52 +09:00 · 2022-03-28 12:46:52 +09:00 · b11c840ed4
parent dc62c8610c 13a8873050
commit b11c840ed4
67 changed files with 3707 additions and 296 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -273,8 +273,12 @@ src/engine/platform/sound/swan.cpp

 src/engine/platform/sound/k005289/k005289.cpp

+src/engine/platform/sound/n163/n163.cpp
+
 src/engine/platform/sound/vic20sound.c

+src/engine/platform/sound/vrcvi/vrcvi.cpp
+
 src/engine/platform/ym2610Interface.cpp

 src/engine/blip_buf.c
@ -322,8 +326,10 @@ src/engine/platform/lynx.cpp
 src/engine/platform/swan.cpp
 src/engine/platform/vera.cpp
 src/engine/platform/bubsyswsg.cpp
+src/engine/platform/n163.cpp
 src/engine/platform/pet.cpp
 src/engine/platform/vic20.cpp
+src/engine/platform/vrc6.cpp
 src/engine/platform/dummy.cpp
 )

--- a/papers/doc/3-pattern/effects.md
+++ b/papers/doc/3-pattern/effects.md
@ -47,13 +47,15 @@ however, effects are continuous, which means you only need to type it once and t
 - `ECxx`: note off after `xx` ticks.
 - `EDxx`: delay note by `xx` ticks.
 - `EExx`: send external command.
-  - currently not used, but this eventually will allow you to do special things after I add VGM export.
+  - this effect is currently incomplete.
 - `EFxx`: add or subtract global pitch.
  - this effect is rather weird. use with caution.
  - `80` is center.
 - `F0xx`: change song Hz by BPM value.
 - `F1xx`: single tick slide up.
 - `F2xx`: single tick slide down.
+- `F3xx`: fine volume slide up (64x slower than `0Axy`).
+- `F4xx`: fine volume slide down (64x slower than `0Axy`).
 - `F8xx`: single tick volume slide up.
 - `F9xx`: single tick volume slide down.
 - `FAxy`: fast volume slide (4x faster than `0Axy`).
--- a/papers/doc/4-instrument/README.md
+++ b/papers/doc/4-instrument/README.md
@ -27,6 +27,8 @@ depending on the instrument type, there are currently 13 different types of an i
 - [VERA](vera.md) - for use with Commander X16 VERA.
 - [Seta/Allumer X1-010](x1_010.md) - for use with Wavetable portion in Seta/Allumer X1-010.
 - [Konami SCC/Bubble System WSG](scc.md) - for use with Konami SCC and Wavetable portion in Bubble System's sound hardware.
+- [Namco 163](n163.md) - for use with Namco 163.
+- [Konami VRC6](vrc6.md) - for use with VRC6's PSG sound source.

 # macros

--- a/papers/doc/4-instrument/n163.md
+++ b/papers/doc/4-instrument/n163.md
@ -0,0 +1,23 @@
+# Namco 163 instrument editor
+
+Namco 163 instrument editor consists of two tabs: one controlling various parameters for waveform initialize and macro tab containing 10 macros.
+
+## N163
+- [Initial Waveform] - Determines the initial waveform for playing.
+- [Initial Waveform position in RAM] - Determines the initial waveform position will be load to RAM.
+- [Initial Waveform length in RAM] - Determines the initial waveform length will be load to RAM.
+- [Load waveform before playback] - Determines the load initial waveform into RAM before playback.
+- [Update waveforms into RAM when every waveform changes] - Determines the update every different waveform changes in playback.
+
+
+## Macros
+- [Volume] - volume levels sequence
+- [Arpeggio]- pitch sequence
+- [Waveform pos.] - sets the waveform source address in RAM for playback (single nibble unit)
+- [Waveform] - sets waveform source for playback immediately or update later
+- [Waveform len.] - sets the waveform source length for playback (4 nibble unit)
+- [Waveform update] - sets the waveform update trigger behavior for playback
+- [Waveform to load] - sets waveform source for load to RAM immediately or later
+- [Wave pos. to load] - sets address of waveform for load to RAM (single nibble unit)
+- [Wave len. to load] - sets length of waveform for load to RAM (4 nibble unit)
+- [Waveform load] - sets the waveform load trigger behavior
--- a/papers/doc/4-instrument/vrc6.md
+++ b/papers/doc/4-instrument/vrc6.md
@ -0,0 +1,7 @@
+# VRC6 instrument editor
+
+VRC6 instrument editor consists of only three macros:
+
+- [Volume] - volume sequence
+- [Arpeggio] - pitch sequence
+- [Duty cycle] - specifies duty cycle for pulse wave channels
--- a/papers/doc/5-wave/README.md
+++ b/papers/doc/5-wave/README.md
@ -2,4 +2,4 @@

 Wavetable synthizers, in context of Furnace, are sound sources that operate on extremely short n-bit PCM streams. By extremely short, no more than 256 bytes. This amount of space is nowhere near enough to store an actual sampled sound, it allows certain amount of freedom to define a waveform shape. As of Furnace 0.5.8, wavetable editor affects PC Engine, WonderSwan and channel 3 of Game Boy.

-Furnace's wavetable editor is rather simple, you can draw the waveform using mouse or by pasting an MML bit stream in the input field. Maximum wave width (length) is 256 bytes, and maximum wave height (depth) is 256. NOTE: Game Boy, PCE, WonderSwan and Bubble System can handle max 32 byte waveforms, X1-010 can handle max 128 byte waveforms as of now, with 16-level height for GB, X1-010 Envelope, WS and Bubble System, and 32-level height for PCE. If larger wave will be defined for these systems, it will be squashed to fit within the constraints of the system.  
+Furnace's wavetable editor is rather simple, you can draw the waveform using mouse or by pasting an MML bit stream in the input field. Maximum wave width (length) is 256 bytes, and maximum wave height (depth) is 256. NOTE: Game Boy, PCE, WonderSwan and Bubble System can handle max 32 byte waveforms, X1-010 can handle max 128 byte waveforms as of now, with 16-level height for GB, X1-010 Envelope, WS, Bubble System and N163, and 32-level height for PCE. If larger wave will be defined for these systems, it will be squashed to fit within the constraints of the system.  
--- a/papers/doc/7-systems/README.md
+++ b/papers/doc/7-systems/README.md
@ -24,8 +24,11 @@ this is a list of systems that Furnace supports, including each system's effects
 - [Seta/Allumer X1-010](x1-010.md)
 - [WonderSwan](wonderswan.md)
 - [Bubble System WSG](bubblesystem.md)
+- [Namco 163](n163.md)
 - [Yamaha OPL](opl.md)
 - [PC Speaker](pcspkr.md)
 - [Commodore PET](pet.md)
+- [Commodore VIC-20](vic20.md)
+- [Konami VRC6](vrc6.md)

 Furnace also reads .dmf files with the [Yamaha YMU759](ymu759.md) system, but...
--- a/papers/doc/7-systems/amiga.md
+++ b/papers/doc/7-systems/amiga.md
@ -6,4 +6,8 @@ in this very computer music trackers were born...

 # effects

-none. as of this moment the Amiga doesn't need any effects in particular, but some may be added in a future.
+- `10xx`: toggle low-pass filter. `0` turns it off and `1` turns it on.
+- `11xx`: toggle amplitude modulation with the next channel.
+  - does not work on the last channel.
+- `12xx`: toggle period (frequency) modulation with the next channel.
+  - does not work on the last channel.
--- a/papers/doc/7-systems/ay8910.md
+++ b/papers/doc/7-systems/ay8910.md
@ -1,8 +1,8 @@
 # General Instrument AY-3-8910

-this chip was used in several home computers (ZX Spectrum, MSX, Amstrad CPC, Atari ST, etc.), video game consoles (Intellivision and Vectrex), arcade boards and even slot machines!
+this chip was used in many home computers (ZX Spectrum, MSX, Amstrad CPC, Atari ST, etc.), video game consoles (Intellivision and Vectrex), arcade boards and even slot machines!

-the chip's powerful sound comes from the envelope...
+It is a 3-channel PSG sound source. The chip's powerful sound comes from the envelope...

 AY-3-8914 variant was used in Intellivision, it's basically original AY with 4 level envelope volume per channel and different register format.

@ -39,4 +39,8 @@ AY-3-8914 variant was used in Intellivision, it's basically original AY with 4 l
  - in this mode the envelope period is set to the channel's notes, multiplied by a fraction.
  - `x` is the numerator.
  - `y` is the denominator.
-  - if `x` or `y` are 0 this will disable auto-envelope mode.
+  - if `x` or `y` are 0 this will disable auto-envelope mode.
+- `2Exx`: write to I/O port A.
+  - this changes the port's mode to "write". make sure you have connected something to it.
+- `2Fxx`: write to I/O port B.
+  - this changes the port's mode to "write". make sure you have connected something to it.
--- a/papers/doc/7-systems/n163.md
+++ b/papers/doc/7-systems/n163.md
@ -0,0 +1,25 @@
+# Namco 163
+
+This is Namco's one of NES mapper, with up to 8 wavetable channels. It has also 128 byte of internal RAM, both channel register and wavetables are stored here. Wavetables are variable size and freely allocable anywhere in RAM, it means it can be uses part of or continuously pre-loaded waveform and/or its sequences in RAM. But waveform RAM area becomes smaller as much as activating more channels; Channel register consumes 8 byte for each channels. You must avoid conflict with channel register area and waveform for avoid channel playback broken.
+
+It has can be outputs only single channel at clock; so it's sound quality is more crunchy as much as activating more channels.
+
+Furnace supports both load waveform into RAM and waveform playback simultaneously, and channel limit is dynamically changeable with effect commands.
+You must load waveform to RAM first for playback or do something, its load behavior is changeable to auto-update when every waveform changes or manual update.
+Both waveform playback and load command is works independently per each channel columns, (Global) commands are don't care about the channel columns for work commands and its load behavior is independent with per-channel column load commands.
+
+# effects
+
+- `10xx`: set waveform for playback.
+- `11xx`: set waveform position in RAM for playback. (single nibble unit)
+- `12xx`: set waveform length in RAM for playback. (04 to FC, 4 nibble unit)
+- `130x`: set playback waveform update behavior. (0: off, bit 0: update now, bit 1: update when every waveform is changed)
+- `14xx`: set waveform for load to RAM.
+- `15xx`: set waveform position for load to RAM. (single nibble unit)
+- `16xx`: set waveform length for load to RAM. (04 to FC, 4 nibble unit)
+- `170x`: set waveform load behavior. (0: off, bit 0: load now, bit 1: load when every waveform is changed)
+- `180x`: set channel limit (0 to 7, x + 1)
+- `20xx`: (Global) set waveform for load to RAM.
+- `21xx`: (Global) set waveform position for load to RAM. (single nibble unit)
+- `22xx`: (Global) set waveform length for load to RAM. (04 to FC, 4 nibble unit)
+- `230x`: (Global) set waveform load behavior. (0: off, bit 0: load now, bit 1: load when every waveform is changed)
--- a/papers/doc/7-systems/nes.md
+++ b/papers/doc/7-systems/nes.md
@ -2,7 +2,7 @@

 the console from Nintendo that plays Super Mario Bros. and helped revive the agonizing video game market in the US during mid-80s.

-also known as Famicom.
+also known as Famicom. It is a five-channel PSG: first two channels play pulse wave with three different duty cycles, third is a fixed-volume triangle channel, fourth is a noise channel (can work in both pseudo-random and periodic modes) and  fifth is a (D)PCM sample channel

 # effects

@ -15,4 +15,4 @@ also known as Famicom.
 - `14xy`: setup sweep down.
  - `x` is the time.
  - `y` is the shift.
-  - set to 0 to disable it.
+  - set to 0 to disable it.
--- a/papers/doc/7-systems/opl.md
+++ b/papers/doc/7-systems/opl.md
@ -5,15 +5,14 @@ a series of FM sound chips which were very popular in DOS land. it was so popula
 essentially a downgraded version of Yamaha's other FM chips, with only 2 operators per channel.
 however, it also had a drums mode, and later chips in the series added more waveforms (than just the typical sine) and even a 4-operator mode.

-the original OPL was present as an expansion for the Commodore 64 and MSX computers (erm, a variant of it). it only had 9 channels and drums mode.
+the original OPL (Yamaha YM3526) was present as an expansion for the Commodore 64 and MSX computers (erm, a variant of it). it only had 9 two-operator channels and drums mode.

-its successor, the OPL2, added 3 more waveforms and was one of the more popular chips because it was present on the AdLib card for PC.
+its successor, the OPL2 (Yamaha YM3812), added 3 more waveforms and was one of the more popular chips because it was present on the AdLib card for PC.
 later Creative would borrow the chip to make the Sound Blaster, and totally destroyed AdLib's dominance.

-the OPL3 added 9 more channels, 4 more waveforms, 4-operator mode (pairing up to 12 channels to make up to six 4-operator channels), quadraphonic output (sadly Furnace only supports stereo) and some other things.
-it was overkill.
+the OPL3 (Yamaha YMF262) added 9 more channels, 4 more waveforms, rudimentary 4-operator mode (pairing up to 12 channels to make up to six 4-operator channels), quadraphonic output (sadly Furnace only supports stereo) and some other things.

-afterwards everyone moved to Windows and software mixing...
+afterwards everyone moved to Windows and software mixed PCM streaming...

 # effects

--- a/papers/doc/7-systems/opll.md
+++ b/papers/doc/7-systems/opll.md
@ -1,6 +1,6 @@
 # Yamaha YM2413/OPLL

-the YM2413, otherwise known as OPLL, is a cost-reduced FM synthesis sound chip manufactured by Yamaha Corporation and based on the Yamaha YM3812 sound chip (OPL2). thought OPL was downgraded enough? :p
+the YM2413, otherwise known as OPLL, is a cost-reduced FM synthesis sound chip, based on the Yamaha YM3812 (OPL2). thought OPL was downgraded enough? :p

 # technical specifications

--- a/papers/doc/7-systems/pce.md
+++ b/papers/doc/7-systems/pce.md
@ -1,9 +1,11 @@
 # PC Engine/TurboGrafx-16

-a console from NEC that attempted to enter the fierce battle between Nintendo and Sega, but because its capabilities are a mix of third and fourth generation, it failed to last long.
+a console from NEC that, depending on a region:
+ attempted to enter the fierce battle between Nintendo and Sega, but because its capabilities are a mix of third and fourth generation, it failed to last long. (US and Europe)
+ was Nintendo's most fearsome rival, completely defeating Sega Mega Drive and defending itself against Super Famicom (Japan)

 it has 6 wavetable channels and the last two ones also double as noise channels.
-furthermore, it has some PCM!
+furthermore, it has some PCM and LFO!

 # effects

--- a/papers/doc/7-systems/pcspkr.md
+++ b/papers/doc/7-systems/pcspkr.md
@ -1,6 +1,6 @@
 # PC Speaker

-40 years of one square beep - and still going!
+40 years of one square beep - and still going! Single channel, no volume control...

 # effects

--- a/papers/doc/7-systems/sms.md
+++ b/papers/doc/7-systems/sms.md
@ -2,7 +2,7 @@

 the predecessor to Genesis.

-surely had better graphics than NES, but its sound is subject of several jokes.
+surely had better graphics than NES, but its sound (fairly weak, 4ch PSG with A-3 is a lowest tone) is subject of several jokes.

 this console is powered by a derivative of the Texas Instruments SN76489.

--- a/papers/doc/7-systems/vic20.md
+++ b/papers/doc/7-systems/vic20.md
@ -0,0 +1,11 @@
+# Commodore VIC-20
+
+The Commodore VIC-20 was Commodore's major attempt at making a personal home computer, and is the percursor to the Commodore 64. The VIC-20 was also known as the VC-20 in Germany, and the VIC-1001 in Japan.
+
+It has 4 PSG voices that has a limited but wide tuning range, and like the SN76489, the last voice is dedicated to playing pseudo-white noise.
+
+The 3 pulse wave channels also have different octaves that they can play notes on. The first channel is the bass channel, and it can play notes from octave 1. The next is the 'mid/chord' channel, and it plays notes from octave 2. And rather obviously, the 3rd pulse channel is typically the lead channel, can play notes from octave 3.
+
+## effect commands
+
+ - `10xx` Switch waveform (`xx` from `00` to `0F`)
--- a/papers/doc/7-systems/vrc6.md
+++ b/papers/doc/7-systems/vrc6.md
@ -0,0 +1,16 @@
+# Konami VRC6
+
+the most popular expansion chip to the NES' sound system.
+
+the chip has 2 pulse wave channels and one sawtooth channel.
+volume register is 4 bit for pulse wave and 6 bit for sawtooth, but sawtooth output is corrupted when volume register value is too high. because this register is actually an 8 bit accumulator, its output may wrap around.
+
+pulse wave duty cycle is 8-level. it can be ignored and it has potential for DAC at this case: volume register in this mode is DAC output and it can be PCM playback through this mode.
+Furnace supports this routine for PCM playback, but it consumes a lot of CPU time in real hardware (even if conjunction with VRC6's integrated IRQ timer).
+
+# effects
+
+these effects only are effective in the pulse channels.
+
+- `12xx`: set duty cycle (0 to 7).
+- `17xx`: toggle PCM mode.
--- a/papers/doc/7-systems/wonderswan.md
+++ b/papers/doc/7-systems/wonderswan.md
@ -1,11 +1,8 @@
 # WonderSwan

-A handheld console released only in Japan by Bandai. Designed by the same
-people behind Game Boy and Virtual Boy, it has lots of similar elements from
-those two systems in the sound department.
+A handheld console released only in Japan by Bandai. Designed by the same people behind Game Boy and Virtual Boy, it has lots of similar elements from those two systems in the sound department.

-It has 4 wavetable channels, one channel could play PCM, the other has hardware
-sweep and the other could play noise.
+It has 4 wavetable channels, channel #2 could play PCM, channel #3 has hardware sweep and channel #4 could play noise.

 # effects

--- a/papers/doc/7-systems/x1-010.md
+++ b/papers/doc/7-systems/x1-010.md
@ -1,27 +1,27 @@
 # Seta/Allumer X1-010

-One of sound chip originally designed by Seta, mainly used at their arcade hardwares at late-80s to early-2000s.
-It has 2 output channels, but no known hardware using this feature for stereo sound.
+A sound chip designed by Seta, mainly used in their own arcade hardware from the late 80s to the early 2000s.
+It has 2 output channels, but there is no known hardware taking advantage of stereo sound capabilities.
 Later hardware paired this with external bankswitching logic, but this isn't emulated yet.
-Allumer one is just rebadged Seta's thing for use in their arcade hardwares.
+Allumer rebadged it for their own arcade hardware.

-It has 16 channels, and all channels can be switchable to PCM sample or wavetable playback mode.
-Wavetable needs to paired with envelope, this feature is similar as AY PSG, but its shape are stored at RAM: it means it is user-definable.
+It has 16 channels, which can all be switched between PCM sample or wavetable playback mode.
+Wavetable playback needs to paired with envelope, similar to AY PSG, but shapes are stored in RAM and as such are user-definable.

-In furnace, this chip is can be configurable for original arcade mono output or stereo output - it simulates early 'incorrect' emulation on some mono hardware, but it is also based on the assumption that each channel is connected to each output.
+In furnace, this chip can be configured for original arcade mono output or stereo output - it simulates early 'incorrect' emulation on some mono hardware, but it is also based on the assumption that each channel is connected to each output.

-# waveform type
+# waveform types

-This chip supports 2 type waveforms, needs to paired external 8 KB RAM for use these features:
+This chip supports 2 types of waveforms, needs to be paired to external 8 KB RAM to access these features:

-One is signed 8 bit mono waveform, it's operated like other wavetable based sound systems.
-These are stored at the bottom half of RAM at common case.
+One is a signed 8 bit mono waveform, operated like other wavetable based sound systems.
+These are stored at the lower half of RAM at common case.

-Another one ("Envelope") is 4 bit stereo waveform, it's multiplied with above and calculates final output, Each nibble is used for each output channels.
+The other one ("Envelope") is a 4 bit stereo waveform, multiplied with the above and calculates final output, each nibble is used for each output channel.
 These are stored at the upper half of RAM at common case.

-Both waveforms are 128 byte fixed size, it's freely allocated at each half of RAM except channel register area: each half can be stored total 32/31 waveforms at once.
-In furnace, You can set envelope shape split mode. When it sets, its waveform will be split to left half and right half for each outputs. each max size are 128 bytes, total 256 bytes.
+Both waveforms are 128 bytes (fixed size), freely allocated at each half of RAM except the channel register area: each half can store total 32/31 waveforms at once.
+In furnace, you can enable the envelope shape split mode. When it is set, its waveform will be split to the left and right halves for each output. Each max size is 128 bytes, total 256 bytes.

 # effects

@ -31,8 +31,8 @@ In furnace, You can set envelope shape split mode. When it sets, its waveform wi
 - `20xx`: set PCM frequency (1 to FF).
 - `22xx`: set envelope mode.
  - bit 0 sets whether envelope will affect this channel.
-  - bit 1 sets whether envelope one-shot mode. when it sets, channel is halted after envelope cycle is ended.
-  - bit 2 sets whether envelope shape split mode. when it sets, envelope shape will splitted to left half and right half.
+  - bit 1 toggles the envelope one-shot mode. when it is set, channel is halted after envelope cycle is finished.
+  - bit 2 toggles the envelope shape split mode. when it is set, envelope shape will be split to left half and right half.
  - bit 3/5 sets whether the right/left shape will mirror the original one.
  - bit 4/6 sets whether the right/left output will mirror the original one.
 - `23xx`: set envelope period.
--- a/papers/doc/7-systems/ym2151.md
+++ b/papers/doc/7-systems/ym2151.md
@ -1,6 +1,6 @@
 # Yamaha YM2151

-the sound chip powering several arcade boards and the Sharp X1/X68000.
+the sound chip powering several arcade boards and the Sharp X1/X68000. Eight 4-op FM channels, with overpowered LFO and almost unused noise generator.

 it also was present on several pinball machines and synthesizers of the era, and later surpassed by the YM2414 (OPZ) present in the world-famous TX81Z.

--- a/papers/doc/7-systems/ym2610.md
+++ b/papers/doc/7-systems/ym2610.md
@ -2,7 +2,7 @@

 originally an arcade board, but SNK shortly adapted it to a rather expensive video game console with the world's biggest cartridges because some people liked the system so much they wanted a home version of it.

-its soundchip is a 3-in-1: FM, YM2149 (AY-3-8910 clone) and 2 different format ADPCM in a single package!
+its soundchip is a 4-in-1: 4ch 4-op FM, YM2149 (AY-3-8910 clone) and 2 different format ADPCM in a single package!

 # effects

@ -56,4 +56,4 @@ its soundchip is a 3-in-1: FM, YM2149 (AY-3-8910 clone) and 2 different format A
  - in this mode the envelope period is set to the channel's notes, multiplied by a fraction.
  - `x` is the numerator.
  - `y` is the denominator.
-  - if `x` or `y` are 0 this will disable auto-envelope mode.
+  - if `x` or `y` are 0 this will disable auto-envelope mode.
--- a/papers/doc/7-systems/ym2612.md
+++ b/papers/doc/7-systems/ym2612.md
@ -1,6 +1,6 @@
 # Yamaha YM2612

-one of two chips that powered the Sega Genesis.
+one of two chips that powered the Sega Genesis. It is a six-channel, four-operator FM synthesizer. Channel #6 can be turned into 8-bit PCM player.

 # effects

--- a/papers/format.md
+++ b/papers/format.md
@ -29,6 +29,9 @@ furthermore, an `or reserved` indicates this field is always present, but is res

 the format versions are:

+- 73: Furnace dev73
+- 72: Furnace dev72
+- 71: Furnace dev71
 - 70: Furnace dev70
 - 69: Furnace dev69
 - 68: Furnace dev68
@ -238,7 +241,12 @@ size | description
     | this is 2.0f for modules before 59
 --- | **extended compatibility flags** (>=70)
  1  | broken speed selection
- 31  | reserved
+  1  | no slides on first tick (>=71) or reserved
+  1  | next row reset arp pos (>=71) or reserved
+  1  | ignore jump at end (>=71) or reserved
+  1  | buggy portamento after slide (>=72) or reserved
+  1  | new ins affects envelope (Game Boy) (>=72) or reserved
+ 26  | reserved
 ```

 # instrument
@ -508,6 +516,14 @@ size | description
     | - 480 bytes
 2?? | note sample × 120
     | - 240 bytes
+ --- | **Namco 163 data** (>=73)
+  4  | initial waveform
+  1  | wave position
+  1  | wave length
+  1  | wave mode:
+     | - bit 1: update on change
+     | - bit 0: load on playback
+  1  | reserved
 ```

 # wavetable
--- a/src/engine/dispatch.h
+++ b/src/engine/dispatch.h
@ -101,9 +101,15 @@ enum DivDispatchCmds {
  DIV_CMD_AY_NOISE_MASK_AND,
  DIV_CMD_AY_NOISE_MASK_OR,
  DIV_CMD_AY_AUTO_ENVELOPE,
+  DIV_CMD_AY_IO_WRITE,
+  DIV_CMD_AY_AUTO_PWM,

  DIV_CMD_SAA_ENVELOPE,

+  DIV_CMD_AMIGA_FILTER,
+  DIV_CMD_AMIGA_AM,
+  DIV_CMD_AMIGA_PM,
+
  DIV_CMD_LYNX_LFSR_LOAD,
  
  DIV_CMD_QSOUND_ECHO_FEEDBACK,
@ -120,6 +126,19 @@ enum DivDispatchCmds {
  DIV_CMD_WS_SWEEP_TIME,
  DIV_CMD_WS_SWEEP_AMOUNT,

+  DIV_CMD_N163_WAVE_POSITION,
+  DIV_CMD_N163_WAVE_LENGTH,
+  DIV_CMD_N163_WAVE_MODE,
+  DIV_CMD_N163_WAVE_LOAD,
+  DIV_CMD_N163_WAVE_LOADPOS,
+  DIV_CMD_N163_WAVE_LOADLEN,
+  DIV_CMD_N163_WAVE_LOADMODE,
+  DIV_CMD_N163_CHANNEL_LIMIT,
+  DIV_CMD_N163_GLOBAL_WAVE_LOAD,
+  DIV_CMD_N163_GLOBAL_WAVE_LOADPOS,
+  DIV_CMD_N163_GLOBAL_WAVE_LOADLEN,
+  DIV_CMD_N163_GLOBAL_WAVE_LOADMODE,
+
  DIV_ALWAYS_SET_VOLUME,

  DIV_CMD_MAX
--- a/src/engine/dispatchContainer.cpp
+++ b/src/engine/dispatchContainer.cpp
@ -46,8 +46,10 @@
 #include "platform/swan.h"
 #include "platform/lynx.h"
 #include "platform/bubsyswsg.h"
+#include "platform/n163.h"
 #include "platform/pet.h"
 #include "platform/vic20.h"
+#include "platform/vrc6.h"
 #include "platform/dummy.h"
 #include "../ta-log.h"
 #include "song.h"
@ -277,12 +279,18 @@ void DivDispatchContainer::init(DivSystem sys, DivEngine* eng, int chanCount, do
    case DIV_SYSTEM_BUBSYS_WSG:
      dispatch=new DivPlatformBubSysWSG;
      break;
+    case DIV_SYSTEM_N163:
+      dispatch=new DivPlatformN163;
+      break;
    case DIV_SYSTEM_PET:
      dispatch=new DivPlatformPET;
      break;
    case DIV_SYSTEM_VIC20:
      dispatch=new DivPlatformVIC20;
      break;
+    case DIV_SYSTEM_VRC6:
+      dispatch=new DivPlatformVRC6;
+      break;
    default:
      logW("this system is not supported yet! using dummy platform.\n");
      dispatch=new DivPlatformDummy;
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@ -104,6 +104,10 @@ const char* DivEngine::getEffectDesc(unsigned char effect, int chan) {
      return "F1xx: Single tick note slide up";
    case 0xf2:
      return "F2xx: Single tick note slide down";
+    case 0xf3:
+      return "F3xx: Fine volume slide up";
+    case 0xf4:
+      return "F4xx: Fine volume slide down";
    case 0xf8:
      return "F8xx: Single tick volume slide up";
    case 0xf9:
@ -144,7 +148,7 @@ void DivEngine::walkSong(int& loopOrder, int& loopRow, int& loopEnd) {
          effectVal=pat[k]->data[j][5+(l<<1)];
          if (effectVal<0) effectVal=0;
          if (pat[k]->data[j][4+(l<<1)]==0x0d) {
-            if (nextOrder==-1 && i<song.ordersLen-1) {
+            if (nextOrder==-1 && (i<song.ordersLen-1 || !song.ignoreJumpAtEnd)) {
              nextOrder=i+1;
              nextRow=effectVal;
            }
@ -832,9 +836,15 @@ double DivEngine::calcBaseFreq(double clock, double divider, int note, bool peri

 int DivEngine::calcFreq(int base, int pitch, bool period, int octave) {
  if (song.linearPitch) {
+    // global pitch multiplier
+    int whatTheFuck=(1024+(globalPitch<<6)-(globalPitch<0?globalPitch-6:0));
+    if (whatTheFuck<1) whatTheFuck=1; // avoids division by zero but please kill me
+    pitch+=2048;
+    if (pitch<0) pitch=0;
+    if (pitch>4095) pitch=4095;
    return period?
-            base*pow(2,-(double)pitch/(12.0*128.0))/(98.0+globalPitch*6.0)*98.0:
-            (base*pow(2,(double)pitch/(12.0*128.0))*(98+globalPitch*6))/98;
+            ((base*(reversePitchTable[pitch]))/whatTheFuck):
+            (((base*(pitchTable[pitch]))>>10)*whatTheFuck)/1024;
  }
  return period?
           base-pitch:
@ -952,11 +962,13 @@ void DivEngine::reset() {
    chan[i]=DivChannelState();
    if (i<chans) chan[i].volMax=(disCont[dispatchOfChan[i]].dispatch->dispatch(DivCommand(DIV_CMD_GET_VOLMAX,dispatchChanOfChan[i]))<<8)|0xff;
    chan[i].volume=chan[i].volMax;
+    if (!song.linearPitch) chan[i].vibratoFine=4;
  }
  extValue=0;
  extValuePresent=0;
  speed1=song.speed1;
  speed2=song.speed2;
+  firstTick=false;
  nextSpeed=speed1;
  divider=60;
  if (song.customTempo) {
@ -2849,6 +2861,10 @@ bool DivEngine::init() {
  for (int i=0; i<64; i++) {
    vibTable[i]=127*sin(((double)i/64.0)*(2*M_PI));
  }
+  for (int i=0; i<4096; i++) {
+    reversePitchTable[i]=round(1024.0*pow(2.0,(2048.0-(double)i)/(12.0*128.0)));
+    pitchTable[i]=round(1024.0*pow(2.0,((double)i-2048.0)/(12.0*128.0)));
+  }

  for (int i=0; i<DIV_MAX_CHANS; i++) {
    isMuted[i]=0;
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@ -42,8 +42,8 @@
 #define BUSY_BEGIN_SOFT softLocked=true; isBusy.lock();
 #define BUSY_END isBusy.unlock(); softLocked=false;

-#define DIV_VERSION "dev70"
-#define DIV_ENGINE_VERSION 70
+#define DIV_VERSION "dev73"
+#define DIV_ENGINE_VERSION 73

 // for imports
 #define DIV_VERSION_MOD 0xff01
@ -190,6 +190,7 @@ class DivEngine {
  bool forceMono;
  bool cmdStreamEnabled;
  bool softLocked;
+  bool firstTick;
  int softLockCount;
  int ticks, curRow, curOrder, remainingLoops, nextSpeed;
  double divider;
@ -226,6 +227,8 @@ class DivEngine {
  } sPreview;

  short vibTable[64];
+  int reversePitchTable[4096];
+  int pitchTable[4096];

  blip_buffer_t* samp_bb;
  size_t samp_bbInLen;
@ -682,7 +685,8 @@ class DivEngine {
      halted(false),
      forceMono(false),
      cmdStreamEnabled(false),
-      softLocked(0),
+      softLocked(false),
+      firstTick(false),
      softLockCount(0),
      ticks(0),
      curRow(0),
--- a/src/engine/fileOps.cpp
+++ b/src/engine/fileOps.cpp
@ -145,6 +145,11 @@ bool DivEngine::loadDMF(unsigned char* file, size_t len) {
    ds.newInsTriggersInPorta=true;
    ds.arp0Reset=true;
    ds.brokenSpeedSel=true;
+    ds.noSlidesOnFirstTick=false;
+    ds.rowResetsArpPos=false;
+    ds.ignoreJumpAtEnd=true;
+    ds.buggyPortaAfterSlide=true;
+    ds.gbInsAffectsEnvelope=true;

    // 1.1 compat flags
    if (ds.version>24) {
@ -825,6 +830,15 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
    if (ds.version<69) {
      ds.arp0Reset=false;
    }
+    if (ds.version<71) {
+      ds.noSlidesOnFirstTick=false;
+      ds.rowResetsArpPos=false;
+      ds.ignoreJumpAtEnd=true;
+    }
+    if (ds.version<72) {
+      ds.buggyPortaAfterSlide=true;
+      ds.gbInsAffectsEnvelope=false;
+    }
    ds.isDMF=false;

    reader.readS(); // reserved
@ -1071,7 +1085,23 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
    if (ds.version>=70) {
      // extended compat flags
      ds.brokenSpeedSel=reader.readC();
-      for (int i=0; i<31; i++) {
+      if (ds.version>=71) {
+        ds.noSlidesOnFirstTick=reader.readC();
+        ds.rowResetsArpPos=reader.readC();
+        ds.ignoreJumpAtEnd=reader.readC();
+      } else {
+        reader.readC();
+        reader.readC();
+        reader.readC();
+      }
+      if (ds.version>=72) {
+        ds.buggyPortaAfterSlide=reader.readC();
+        ds.gbInsAffectsEnvelope=reader.readC();
+      } else {
+        reader.readC();
+        reader.readC();
+      }
+      for (int i=0; i<26; i++) {
        reader.readC();
      }
    }
@ -1282,6 +1312,10 @@ bool DivEngine::loadMod(unsigned char* file, size_t len) {
    DivSong ds;
    ds.tuning=436.0;
    ds.version=DIV_VERSION_MOD;
+    ds.linearPitch=false;
+    ds.noSlidesOnFirstTick=true;
+    ds.rowResetsArpPos=true;
+    ds.ignoreJumpAtEnd=false;

    int insCount=31;
    bool bypassLimits=false;
@ -1539,6 +1573,9 @@ bool DivEngine::loadMod(unsigned char* file, size_t len) {
              fxTyp=fxVal>>4;
              fxVal&=0x0f;
              switch (fxTyp) {
+                case 0:
+                  writeFxCol(0x10,!fxVal);
+                  break;
                case 1: // single note slide up
                case 2: // single note slide down
                  writeFxCol(fxTyp-1+0xf1,fxVal);
@ -1579,7 +1616,7 @@ bool DivEngine::loadMod(unsigned char* file, size_t len) {
    ds.systemLen=(chCount+3)/4;
    for(int i=0; i<ds.systemLen; i++) {
      ds.system[i]=DIV_SYSTEM_AMIGA;
-      ds.systemFlags[i]=1|(80<<8)|(bypassLimits?4:0); // PAL
+      ds.systemFlags[i]=1|(80<<8)|(bypassLimits?4:0)|((ds.systemLen>1 || bypassLimits)?2:0); // PAL
    }
    for(int i=0; i<chCount; i++) {
      ds.chanShow[i]=true;
@ -1916,7 +1953,12 @@ SafeWriter* DivEngine::saveFur(bool notPrimary) {

  // extended compat flags
  w->writeC(song.brokenSpeedSel);
-  for (int i=0; i<31; i++) {
+  w->writeC(song.noSlidesOnFirstTick);
+  w->writeC(song.rowResetsArpPos);
+  w->writeC(song.ignoreJumpAtEnd);
+  w->writeC(song.buggyPortaAfterSlide);
+  w->writeC(song.gbInsAffectsEnvelope);
+  for (int i=0; i<26; i++) {
    w->writeC(0);
  }

--- a/src/engine/instrument.cpp
+++ b/src/engine/instrument.cpp
@ -385,6 +385,13 @@ void DivInstrument::putInsData(SafeWriter* w) {
    w->write(amiga.noteFreq,120*sizeof(unsigned int));
    w->write(amiga.noteMap,120*sizeof(short));
  }
+
+  // N163
+  w->writeI(n163.wave);
+  w->writeC(n163.wavePos);
+  w->writeC(n163.waveLen);
+  w->writeC(n163.waveMode);
+  w->writeC(0); // reserved
 }

 DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
@ -724,6 +731,13 @@ DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
    std.dutyMacroRel=-1;
  }

+  // clear wave macro if OPLL instrument and version<70
+  if (version<70 && type==DIV_INS_OPLL) {
+    std.waveMacroLen=0;
+    std.waveMacroLoop=-1;
+    std.waveMacroRel=-1;
+  }
+
  // sample map
  if (version>=67) {
    amiga.useNoteMap=reader.readC();
@ -733,6 +747,14 @@ DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
    }
  }

+  // N163
+  if (version>=73) {
+    n163.wave=reader.readI();
+    n163.wavePos=(unsigned char)reader.readC();
+    n163.waveLen=(unsigned char)reader.readC();
+    n163.waveMode=(unsigned char)reader.readC();
+    reader.readC(); // reserved
+  }
  return DIV_DATA_SUCCESS;
 }

--- a/src/engine/instrument.h
+++ b/src/engine/instrument.h
@ -385,6 +385,17 @@ struct DivInstrumentAmiga {
  }
 };

+struct DivInstrumentN163 {
+  int wave, wavePos, waveLen;
+  unsigned char waveMode;
+
+  DivInstrumentN163():
+    wave(-1),
+    wavePos(0),
+    waveLen(32),
+    waveMode(3) {}
+};
+
 struct DivInstrument {
  String name;
  bool mode;
@ -394,6 +405,7 @@ struct DivInstrument {
  DivInstrumentGB gb;
  DivInstrumentC64 c64;
  DivInstrumentAmiga amiga;
+  DivInstrumentN163 n163;
  
  /**
   * save the instrument to a SafeWriter.
--- a/src/engine/platform/amiga.cpp
+++ b/src/engine/platform/amiga.cpp
@ -17,6 +17,7 @@
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

+#define _USE_MATH_DEFINES
 #include "amiga.h"
 #include "../engine.h"
 #include <math.h>
@ -63,10 +64,26 @@ const char** DivPlatformAmiga::getRegisterSheet() {
  return regCheatSheetAmiga;
 }

+const char* DivPlatformAmiga::getEffectName(unsigned char effect) {
+  switch (effect) {
+    case 0x10:
+      return "10xx: Toggle filter (0 disables; 1 enables)";
+      break;
+    case 0x11:
+      return "11xx: Toggle AM with next channel";
+      break;
+    case 0x12:
+      return "12xx: Toggle period modulation with next channel";
+      break;
+  }
+  return NULL;
+}
+
 void DivPlatformAmiga::acquire(short* bufL, short* bufR, size_t start, size_t len) {
+  static int outL, outR;
  for (size_t h=start; h<start+len; h++) {
-    bufL[h]=0;
-    bufR[h]=0;
+    outL=0;
+    outR=0;
    for (int i=0; i<4; i++) {
      if (chan[i].sample>=0 && chan[i].sample<parent->song.sampleLen) {
        chan[i].audSub-=AMIGA_DIVIDER;
@ -74,6 +91,14 @@ void DivPlatformAmiga::acquire(short* bufL, short* bufR, size_t start, size_t le
          DivSample* s=parent->getSample(chan[i].sample);
          if (s->samples>0) {
            chan[i].audDat=s->data8[chan[i].audPos++];
+            if (i<3 && chan[i].useV) {
+              chan[i+1].outVol=(unsigned char)chan[i].audDat^0x80;
+              if (chan[i+1].outVol>64) chan[i+1].outVol=64;
+            }
+            if (i<3 && chan[i].useP) {
+              chan[i+1].freq=(unsigned char)chan[i].audDat^0x80;
+              if (chan[i+1].freq<AMIGA_DIVIDER) chan[i+1].freq=AMIGA_DIVIDER;
+            }
            if (chan[i].audPos>=s->samples || chan[i].audPos>=131071) {
              if (s->loopStart>=0 && s->loopStart<(int)s->samples) {
                chan[i].audPos=s->loopStart;
@ -102,14 +127,20 @@ void DivPlatformAmiga::acquire(short* bufL, short* bufR, size_t start, size_t le
      }
      if (!isMuted[i]) {
        if (i==0 || i==3) {
-          bufL[h]+=((chan[i].audDat*chan[i].outVol)*sep1)>>7;
-          bufR[h]+=((chan[i].audDat*chan[i].outVol)*sep2)>>7;
+          outL+=((chan[i].audDat*chan[i].outVol)*sep1)>>7;
+          outR+=((chan[i].audDat*chan[i].outVol)*sep2)>>7;
        } else {
-          bufL[h]+=((chan[i].audDat*chan[i].outVol)*sep2)>>7;
-          bufR[h]+=((chan[i].audDat*chan[i].outVol)*sep1)>>7;
+          outL+=((chan[i].audDat*chan[i].outVol)*sep2)>>7;
+          outR+=((chan[i].audDat*chan[i].outVol)*sep1)>>7;
        }
      }
    }
+    filter[0][0]+=(filtConst*(outL-filter[0][0]))>>12;
+    filter[0][1]+=(filtConst*(filter[0][0]-filter[0][1]))>>12;
+    filter[1][0]+=(filtConst*(outR-filter[1][0]))>>12;
+    filter[1][1]+=(filtConst*(filter[1][0]-filter[1][1]))>>12;
+    bufL[h]=filter[0][1];
+    bufR[h]=filter[1][1];
  }
 }

@ -299,6 +330,16 @@ int DivPlatformAmiga::dispatch(DivCommand c) {
      chan[c.chan].audPos=c.value;
      chan[c.chan].setPos=true;
      break;
+    case DIV_CMD_AMIGA_FILTER:
+      filterOn=c.value;
+      filtConst=filterOn?filtConstOn:filtConstOff;
+      break;
+    case DIV_CMD_AMIGA_AM:
+      chan[c.chan].useV=c.value;
+      break;
+    case DIV_CMD_AMIGA_PM:
+      chan[c.chan].useP=c.value;
+      break;
    case DIV_CMD_GET_VOLMAX:
      return 64;
      break;
@ -332,7 +373,11 @@ void* DivPlatformAmiga::getChanState(int ch) {
 void DivPlatformAmiga::reset() {
  for (int i=0; i<4; i++) {
    chan[i]=DivPlatformAmiga::Channel();
+    filter[0][i]=0;
+    filter[1][i]=0;
  }
+  filterOn=false;
+  filtConst=filterOn?filtConstOn:filtConstOff;
 }

 bool DivPlatformAmiga::isStereo() {
@ -372,6 +417,13 @@ void DivPlatformAmiga::setFlags(unsigned int flags) {
  sep2=127-((flags>>8)&127);
  amigaModel=flags&2;
  bypassLimits=flags&4;
+  if (amigaModel) {
+    filtConstOff=4000;
+    filtConstOn=sin(M_PI*8000.0/(double)rate)*4096.0;
+  } else {
+    filtConstOff=sin(M_PI*16000.0/(double)rate)*4096.0;
+    filtConstOn=sin(M_PI*5500.0/(double)rate)*4096.0;
+  }
 }

 int DivPlatformAmiga::init(DivEngine* p, int channels, int sugRate, unsigned int flags) {
--- a/src/engine/platform/amiga.h
+++ b/src/engine/platform/amiga.h
@ -36,7 +36,7 @@ class DivPlatformAmiga: public DivDispatch {
    unsigned char ins;
    int busClock;
    int note;
-    bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, useWave, setPos;
+    bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, useWave, setPos, useV, useP;
    signed char vol, outVol;
    DivMacroInt std;
    Channel():
@ -61,6 +61,8 @@ class DivPlatformAmiga: public DivDispatch {
      inPorta(false),
      useWave(false),
      setPos(false),
+      useV(false),
+      useP(false),
      vol(64),
      outVol(64) {}
  };
@ -68,6 +70,11 @@ class DivPlatformAmiga: public DivDispatch {
  bool isMuted[4];
  bool bypassLimits;
  bool amigaModel;
+  bool filterOn;
+
+  int filter[2][4];
+  int filtConst;
+  int filtConstOff, filtConstOn;

  int sep1, sep2;

@ -88,6 +95,7 @@ class DivPlatformAmiga: public DivDispatch {
    void notifyWaveChange(int wave);
    void notifyInsDeletion(void* ins);
    const char** getRegisterSheet();
+    const char* getEffectName(unsigned char effect);
    int init(DivEngine* parent, int channels, int sugRate, unsigned int flags);
    void quit();
 };
--- a/src/engine/platform/ay.cpp
+++ b/src/engine/platform/ay.cpp
@ -19,6 +19,7 @@

 #include "ay.h"
 #include "../engine.h"
+#include "../../ta-log.h"
 #include "sound/ay8910.h"
 #include <string.h>
 #include <math.h>
@ -98,6 +99,12 @@ const char* DivPlatformAY8910::getEffectName(unsigned char effect) {
    case 0x29:
      return "29xy: Set auto-envelope (x: numerator; y: denominator)";
      break;
+    case 0x2e:
+      return "2Exx: Write to I/O port A";
+      break;
+    case 0x2f:
+      return "2Fxx: Write to I/O port B";
+      break;
  }
  return NULL;
 }
@ -141,6 +148,30 @@ void DivPlatformAY8910::acquire(short* bufL, short* bufR, size_t start, size_t l
  }
 }

+void DivPlatformAY8910::updateOutSel(bool immediate) {
+  if (immediate) {
+    immWrite(0x07,
+          ~((chan[0].psgMode&1)|
+           ((chan[1].psgMode&1)<<1)|
+           ((chan[2].psgMode&1)<<2)|
+           ((chan[0].psgMode&2)<<2)|
+           ((chan[1].psgMode&2)<<3)|
+           ((chan[2].psgMode&2)<<4)|
+           ((!ioPortA)<<6)|
+           ((!ioPortB)<<7)));
+  } else {
+    rWrite(0x07,
+          ~((chan[0].psgMode&1)|
+           ((chan[1].psgMode&1)<<1)|
+           ((chan[2].psgMode&1)<<2)|
+           ((chan[0].psgMode&2)<<2)|
+           ((chan[1].psgMode&2)<<3)|
+           ((chan[2].psgMode&2)<<4)|
+           ((!ioPortA)<<6)|
+           ((!ioPortB)<<7)));
+  }
+}
+
 void DivPlatformAY8910::tick() {
  // PSG
  for (int i=0; i<3; i++) {
@ -221,13 +252,7 @@ void DivPlatformAY8910::tick() {
    }
  }

-  rWrite(0x07,
-         ~((chan[0].psgMode&1)|
-         ((chan[1].psgMode&1)<<1)|
-         ((chan[2].psgMode&1)<<2)|
-         ((chan[0].psgMode&2)<<2)|
-         ((chan[1].psgMode&2)<<3)|
-         ((chan[2].psgMode&2)<<4)));
+  updateOutSel();

  if (ayEnvSlide!=0) {
    ayEnvSlideLow+=ayEnvSlide;
@ -401,6 +426,19 @@ int DivPlatformAY8910::dispatch(DivCommand c) {
      chan[c.chan].autoEnvDen=c.value&15;
      chan[c.chan].freqChanged=true;
      break;
+    case DIV_CMD_AY_IO_WRITE:
+      if (c.value) { // port B
+        ioPortB=true;
+        portBVal=c.value2;
+        logI("AY I/O port B write: %x\n",portBVal);
+      } else { // port A
+        ioPortA=true;
+        portAVal=c.value2;
+        logI("AY I/O port A write: %x\n",portAVal);
+      }
+      updateOutSel(true);
+      immWrite(14+(c.value?1:0),(c.value?portBVal:portAVal));
+      break;
    case DIV_ALWAYS_SET_VOLUME:
      return 0;
      break;
@ -486,6 +524,11 @@ void DivPlatformAY8910::reset() {
  delay=0;

  extMode=false;
+
+  ioPortA=false;
+  ioPortB=false;
+  portAVal=0;
+  portBVal=0;
 }

 bool DivPlatformAY8910::isStereo() {
--- a/src/engine/platform/ay.h
+++ b/src/engine/platform/ay.h
@ -65,6 +65,8 @@ class DivPlatformAY8910: public DivDispatch {

    bool extMode;
    bool stereo, sunsoft, intellivision;
+    bool ioPortA, ioPortB;
+    unsigned char portAVal, portBVal;
  
    short oldWrites[16];
    short pendingWrites[16];
@ -75,6 +77,8 @@ class DivPlatformAY8910: public DivDispatch {
    short* ayBuf[3];
    size_t ayBufLen;

+    void updateOutSel(bool immediate=false);
+
    friend void putDispatchChan(void*,int,int);
  
  public:
--- a/src/engine/platform/ay8930.cpp
+++ b/src/engine/platform/ay8930.cpp
@ -19,6 +19,7 @@

 #include "ay8930.h"
 #include "../engine.h"
+#include "../../ta-log.h"
 #include "sound/ay8910.h"
 #include <string.h>
 #include <math.h>
@ -99,6 +100,12 @@ const char* DivPlatformAY8930::getEffectName(unsigned char effect) {
    case 0x29:
      return "29xy: Set auto-envelope (x: numerator; y: denominator)";
      break;
+    case 0x2e:
+      return "2Exx: Write to I/O port A";
+      break;
+    case 0x2f:
+      return "2Fxx: Write to I/O port B";
+      break;
  }
  return NULL;
 }
@ -141,6 +148,30 @@ void DivPlatformAY8930::acquire(short* bufL, short* bufR, size_t start, size_t l
  }
 }

+void DivPlatformAY8930::updateOutSel(bool immediate) {
+  if (immediate) {
+    immWrite(0x07,
+          ~((chan[0].psgMode&1)|
+           ((chan[1].psgMode&1)<<1)|
+           ((chan[2].psgMode&1)<<2)|
+           ((chan[0].psgMode&2)<<2)|
+           ((chan[1].psgMode&2)<<3)|
+           ((chan[2].psgMode&2)<<4)|
+           ((!ioPortA)<<6)|
+           ((!ioPortB)<<7)));
+  } else {
+    rWrite(0x07,
+          ~((chan[0].psgMode&1)|
+           ((chan[1].psgMode&1)<<1)|
+           ((chan[2].psgMode&1)<<2)|
+           ((chan[0].psgMode&2)<<2)|
+           ((chan[1].psgMode&2)<<3)|
+           ((chan[2].psgMode&2)<<4)|
+           ((!ioPortA)<<6)|
+           ((!ioPortB)<<7)));
+  }
+}
+
 const unsigned char regPeriodL[3]={
  0x0b, 0x10, 0x12
 };
@ -262,13 +293,7 @@ void DivPlatformAY8930::tick() {
    }
  }

-  rWrite(0x07,
-         ~((chan[0].psgMode&1)|
-         ((chan[1].psgMode&1)<<1)|
-         ((chan[2].psgMode&1)<<2)|
-         ((chan[0].psgMode&2)<<2)|
-         ((chan[1].psgMode&2)<<3)|
-         ((chan[2].psgMode&2)<<4)));
+  updateOutSel();
  
  for (int i=0; i<32; i++) {
    if (pendingWrites[i]!=oldWrites[i]) {
@ -420,6 +445,19 @@ int DivPlatformAY8930::dispatch(DivCommand c) {
      chan[c.chan].autoEnvDen=c.value&15;
      chan[c.chan].freqChanged=true;
      break;
+    case DIV_CMD_AY_IO_WRITE:
+      if (c.value) { // port B
+        ioPortB=true;
+        portBVal=c.value2;
+        logI("AY I/O port B write: %x\n",portBVal);
+      } else { // port A
+        ioPortA=true;
+        portAVal=c.value2;
+        logI("AY I/O port A write: %x\n",portAVal);
+      }
+      updateOutSel(true);
+      immWrite(14+(c.value?1:0),(c.value?portBVal:portAVal));
+      break;
    case DIV_ALWAYS_SET_VOLUME:
      return 0;
      break;
@ -499,6 +537,11 @@ void DivPlatformAY8930::reset() {
  extMode=false;
  bank=false;

+  ioPortA=false;
+  ioPortB=false;
+  portAVal=0;
+  portBVal=0;
+
  immWrite(0x0d,0xa0);
  immWrite(0x19,2); // and mask
  immWrite(0x1a,0x00); // or mask
--- a/src/engine/platform/ay8930.h
+++ b/src/engine/platform/ay8930.h
@ -54,6 +54,8 @@ class DivPlatformAY8930: public DivDispatch {
    int delay;

    bool extMode, stereo;
+    bool ioPortA, ioPortB;
+    unsigned char portAVal, portBVal;
  
    short oldWrites[32];
    short pendingWrites[32];
@ -64,6 +66,8 @@ class DivPlatformAY8930: public DivDispatch {
    short* ayBuf[3];
    size_t ayBufLen;

+    void updateOutSel(bool immediate=false);
+
    friend void putDispatchChan(void*,int,int);
  
  public:
--- a/src/engine/platform/gb.cpp
+++ b/src/engine/platform/gb.cpp
@ -288,7 +288,11 @@ int DivPlatformGB::dispatch(DivCommand c) {
      if (chan[c.chan].ins!=c.value || c.value2==1) {
        chan[c.chan].ins=c.value;
        if (c.chan!=2) {
-          chan[c.chan].vol=parent->getIns(chan[c.chan].ins)->gb.envVol;
+          DivInstrument* ins=parent->getIns(chan[c.chan].ins);
+          chan[c.chan].vol=ins->gb.envVol;
+          if (parent->song.gbInsAffectsEnvelope) {
+            rWrite(16+c.chan*5+2,((chan[c.chan].vol<<4))|(ins->gb.envLen&7)|((ins->gb.envDir&1)<<3));
+          }
        }
      }
      break;
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@ -92,7 +92,9 @@ void DivPlatformGenesis::acquire_nuked(short* bufL, short* bufR, size_t start, s
        DivSample* s=parent->getSample(dacSample);
        if (s->samples>0) {
          if (!isMuted[5]) {
-            urgentWrite(0x2a,(unsigned char)s->data8[dacPos]+0x80);
+            if (writes.size()<16) {
+              urgentWrite(0x2a,(unsigned char)s->data8[dacPos]+0x80);
+            }
          }
          if (++dacPos>=s->samples) {
            if (s->loopStart>=0 && s->loopStart<(int)s->samples) {
@ -159,7 +161,9 @@ void DivPlatformGenesis::acquire_ymfm(short* bufL, short* bufR, size_t start, si
        DivSample* s=parent->getSample(dacSample);
        if (s->samples>0) {
          if (!isMuted[5]) {
-            urgentWrite(0x2a,(unsigned char)s->data8[dacPos]+0x80);
+            if (writes.size()<16) {
+              urgentWrite(0x2a,(unsigned char)s->data8[dacPos]+0x80);
+            }
          }
          if (++dacPos>=s->samples) {
            if (s->loopStart>=0 && s->loopStart<(int)s->samples) {
--- a/src/engine/platform/genesisshared.h
+++ b/src/engine/platform/genesisshared.h
@ -44,6 +44,17 @@ static int orderedOps[4]={

 #define rWrite(a,v) if (!skipRegisterWrites) {pendingWrites[a]=v;}
 #define immWrite(a,v) if (!skipRegisterWrites) {writes.push_back(QueuedWrite(a,v)); if (dumpWrites) {addWrite(a,v);} }
-#define urgentWrite(a,v) if (!skipRegisterWrites) {if (writes.empty() || writes.front().addrOrVal) {writes.push_back(QueuedWrite(a,v));} else {writes.push_front(QueuedWrite(a,v));}; if (dumpWrites) {addWrite(a,v);} }
+#define urgentWrite(a,v) if (!skipRegisterWrites) { \
+  if (writes.empty()) { \
+    writes.push_back(QueuedWrite(a,v)); \
+  } else if (writes.size()>16 || writes.front().addrOrVal) { \
+    writes.push_back(QueuedWrite(a,v)); \
+  } else { \
+    writes.push_front(QueuedWrite(a,v)); \
+  } \
+  if (dumpWrites) { \
+    addWrite(a,v); \
+  } \
+}

 #include "fmshared_OPN.h"
--- a/src/engine/platform/n163.cpp
+++ b/src/engine/platform/n163.cpp
@ -0,0 +1,656 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2022 tildearrow and contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "n163.h"
+#include "../engine.h"
+#include <math.h>
+
+#define rRead(a,v) n163->addr_w(a); n163->data_r(v);
+#define rWrite(a,v) if (!skipRegisterWrites) {writes.emplace(a,v); if (dumpWrites) {addWrite(a,v);} }
+#define rWriteMask(a,v,m) if (!skipRegisterWrites) {writes.emplace(a,v,m); if (dumpWrites) {addWrite(a,v);} }
+#define chWrite(c,a,v) \
+  if (c<=chanMax) { \
+    rWrite(0x78-(c<<3)+(a&7),v) \
+  }
+
+#define chWriteMask(c,a,v,m) \
+  if (c<=chanMax) { \
+    rWriteMask(0x78-(c<<3)+(a&7),v,m) \
+  }
+
+#define CHIP_FREQBASE (15*32768)
+
+const char* regCheatSheetN163[]={
+  "FreqL7", "40",
+  "AccL7", "41",
+  "FreqM7", "42",
+  "AccM7", "43",
+  "WavLen_FreqH7", "44",
+  "AccH7", "45",
+  "WavPos7", "46",
+  "Vol7", "47",
+  "FreqL6", "48",
+  "AccL6", "49",
+  "FreqM6", "4A",
+  "AccM6", "4B",
+  "WavLen_FreqH6", "4C",
+  "AccH6", "4D",
+  "WavPos6", "4E",
+  "Vol6", "4F",
+  "FreqL5", "50",
+  "AccL5", "51",
+  "FreqM5", "52",
+  "AccM5", "53",
+  "WavLen_FreqH5", "54",
+  "AccH5", "55",
+  "WavPos5", "56",
+  "Vol5", "57",
+  "FreqL4", "58",
+  "AccL4", "59",
+  "FreqM4", "5A",
+  "AccM4", "5B",
+  "WavLen_FreqH4", "5C",
+  "AccH4", "5D",
+  "WavPos4", "5E",
+  "Vol4", "5F",
+  "FreqL3", "60",
+  "AccL3", "61",
+  "FreqM3", "62",
+  "AccM3", "63",
+  "WavLen_FreqH3", "64",
+  "AccH3", "65",
+  "WavPos3", "66",
+  "Vol3", "67",
+  "FreqL2", "68",
+  "AccL2", "69",
+  "FreqM2", "6A",
+  "AccM2", "6B",
+  "WavLen_FreqH2", "6C",
+  "AccH2", "6D",
+  "WavPos2", "6E",
+  "Vol2", "6F",
+  "FreqL1", "70",
+  "AccL1", "71",
+  "FreqM1", "72",
+  "AccM1", "73",
+  "WavLen_FreqH1", "74",
+  "AccH1", "75",
+  "WavPos1", "76",
+  "Vol1", "77",
+  "FreqL0", "78",
+  "AccL0", "79",
+  "FreqM0", "7A",
+  "AccM0", "7B",
+  "WavLen_FreqH0", "7C",
+  "AccH0", "7D",
+  "WavPos0", "7E",
+  "ChanMax_Vol0", "7F",
+  NULL
+};
+
+const char** DivPlatformN163::getRegisterSheet() {
+  return regCheatSheetN163;
+}
+
+const char* DivPlatformN163::getEffectName(unsigned char effect) {
+  switch (effect) {
+    case 0x10:
+      return "10xx: Select waveform";
+      break;
+    case 0x11:
+      return "11xx: Set waveform position in RAM (single nibble unit)";
+      break;
+    case 0x12:
+      return "12xx: Set waveform length in RAM (04 to FC, 4 nibble unit)";
+      break;
+    case 0x13:
+      return "130x: Change waveform update mode (0: off, bit 0: update now, bit 1: update when every waveform changes)";
+      break;
+    case 0x14:
+      return "14xx: Select waveform for load to RAM";
+      break;
+    case 0x15:
+      return "15xx: Set waveform position for load to RAM (single nibble unit)";
+      break;
+    case 0x16:
+      return "16xx: Set waveform length for load to RAM (04 to FC, 4 nibble unit)";
+      break;
+    case 0x17:
+      return "170x: Change waveform load mode (0: off, bit 0: load now, bit 1: load when every waveform changes)";
+      break;
+    case 0x18:
+      return "180x: Change channel limits (0 to 7, x + 1)";
+      break;
+    case 0x20:
+      return "20xx: (Global) Select waveform for load to RAM";
+      break;
+    case 0x21:
+      return "21xx: (Global) Set waveform position for load to RAM (single nibble unit)";
+      break;
+    case 0x22:
+      return "22xx: (Global) Set waveform length for load to RAM (04 to FC, 4 nibble unit)";
+      break;
+    case 0x23:
+      return "230x: (Global) Change waveform load mode (0: off, bit 0: load now, bit 1: load when every waveform changes)";
+      break;
+  }
+  return NULL;
+}
+
+void DivPlatformN163::acquire(short* bufL, short* bufR, size_t start, size_t len) {
+  for (size_t i=start; i<start+len; i++) {
+    n163->tick();
+    int out=(n163->out()<<6)*(chanMax+1); // scale to 16 bit
+    if (out>32767) out=32767;
+    if (out<-32768) out=-32768;
+    bufL[i]=bufR[i]=out;
+
+    // command queue
+    while (!writes.empty()) {
+      QueuedWrite w=writes.front();
+      n163->addr_w(w.addr);
+      n163->data_w((n163->data_r()&~w.mask)|(w.val&w.mask));
+      writes.pop();
+    }
+  }
+}
+
+void DivPlatformN163::updateWave(int wave, int pos, int len) {
+  len&=0xfc; // 4 nibble boundary
+  DivWavetable* wt=parent->getWave(wave);
+  for (int i=0; i<len; i++) {
+    unsigned char addr=(pos+i); // address (nibble each)
+    if (addr>=((0x78-(chanMax<<3))<<1)) { // avoid conflict with channel register area
+      break;
+    }
+    unsigned char mask=(addr&1)?0xf0:0x0f;
+    if (wt->max<1 || wt->len<1) {
+      rWriteMask(addr>>1,0,mask);
+    } else {
+      int data=wt->data[i*wt->len/len]*15/wt->max;
+      if (data<0) data=0;
+      if (data>15) data=15;
+      rWriteMask(addr>>1,(addr&1)?(data<<4):(data&0xf),mask);
+    }
+  }
+}
+
+void DivPlatformN163::updateWaveCh(int ch) {
+  if (ch<=chanMax) {
+    updateWave(chan[ch].wave,chan[ch].wavePos,chan[ch].waveLen);
+    if (chan[ch].active) {
+      chan[ch].volumeChanged=true;
+    }
+  }
+}
+
+void DivPlatformN163::tick() {
+  for (int i=0; i<=chanMax; i++) {
+    chan[i].std.next();
+    if (chan[i].std.hadVol) {
+      chan[i].outVol=(MIN(15,chan[i].std.vol)*(chan[i].vol&15))/15;
+      if (chan[i].outVol<0) chan[i].outVol=0;
+      if (chan[i].outVol>15) chan[i].outVol=15;
+      if (chan[i].resVol!=chan[i].outVol) {
+        chan[i].resVol=chan[i].outVol;
+        if (!isMuted[i]) {
+          chan[i].volumeChanged=true;
+        }
+      }
+    }
+    if (chan[i].std.hadArp) {
+      if (!chan[i].inPorta) {
+        if (chan[i].std.arpMode) {
+          chan[i].baseFreq=NOTE_FREQUENCY(chan[i].std.arp);
+        } else {
+          chan[i].baseFreq=NOTE_FREQUENCY(chan[i].note+(signed char)chan[i].std.arp);
+        }
+      }
+      chan[i].freqChanged=true;
+    } else {
+      if (chan[i].std.arpMode && chan[i].std.finishedArp) {
+        chan[i].baseFreq=NOTE_FREQUENCY(chan[i].note);
+        chan[i].freqChanged=true;
+      }
+    }
+    if (chan[i].std.hadDuty) {
+      if (chan[i].wavePos!=chan[i].std.duty) {
+        chan[i].wavePos=chan[i].std.duty;
+        if (chan[i].waveMode&0x2) {
+          chan[i].waveUpdated=true;
+        }
+        chan[i].waveChanged=true;
+      }
+    }
+    if (chan[i].std.hadWave) {
+      if (chan[i].wave!=chan[i].std.wave) {
+        chan[i].wave=chan[i].std.wave;
+        if (chan[i].waveMode&0x2) {
+          chan[i].waveUpdated=true;
+        }
+      }
+    }
+    if (chan[i].std.hadEx1) {
+      if (chan[i].waveLen!=(chan[i].std.ex1&0xfc)) {
+        chan[i].waveLen=chan[i].std.ex1&0xfc;
+        if (chan[i].waveMode&0x2) {
+          chan[i].waveUpdated=true;
+        }
+        chan[i].freqChanged=true;
+      }
+    }
+    if (chan[i].std.hadEx2) {
+      if ((chan[i].waveMode&0x2)!=(chan[i].std.ex2&0x2)) { // update when every waveform changed
+        chan[i].waveMode=(chan[i].waveMode&~0x2)|(chan[i].std.ex2&0x2);
+        if (chan[i].waveMode&0x2) {
+          chan[i].waveUpdated=true;
+          chan[i].waveChanged=true;
+        }
+      }
+      if ((chan[i].waveMode&0x1)!=(chan[i].std.ex2&0x1)) { // update waveform now
+        chan[i].waveMode=(chan[i].waveMode&~0x1)|(chan[i].std.ex2&0x1);
+        if (chan[i].waveMode&0x1) { // rising edge
+          chan[i].waveUpdated=true;
+          chan[i].waveChanged=true;
+        }
+      }
+    }
+    if (chan[i].std.hadEx3) {
+      if (chan[i].loadWave!=chan[i].std.ex3) {
+        chan[i].loadWave=chan[i].std.ex3;
+        if (chan[i].loadMode&0x2) {
+          updateWave(chan[i].loadWave,chan[i].loadPos,chan[i].loadLen&0xfc);
+        }
+      }
+    }
+    if (chan[i].std.hadAlg) {
+      if (chan[i].loadPos!=chan[i].std.alg) {
+        chan[i].loadPos=chan[i].std.alg;
+      }
+    }
+    if (chan[i].std.hadFb) {
+      if (chan[i].loadLen!=(chan[i].std.fb&0xfc)) {
+        chan[i].loadLen=chan[i].std.fb&0xfc;
+      }
+    }
+    if (chan[i].std.hadFms) {
+      if ((chan[i].loadMode&0x2)!=(chan[i].std.fms&0x2)) { // load when every waveform changes
+        chan[i].loadMode=(chan[i].loadMode&~0x2)|(chan[i].std.fms&0x2);
+      }
+      if ((chan[i].loadMode&0x1)!=(chan[i].std.fms&0x1)) { // load now
+        chan[i].loadMode=(chan[i].loadMode&~0x1)|(chan[i].std.fms&0x1);
+        if (chan[i].loadMode&0x1) { // rising edge
+          updateWave(chan[i].loadWave,chan[i].loadPos,chan[i].loadLen&0xfc);
+        }
+      }
+    }
+    if (chan[i].volumeChanged) {
+      if ((!chan[i].active) || isMuted[i]) {
+        chWriteMask(i,0x7,0,0xf);
+      } else {
+        chWriteMask(i,0x7,chan[i].resVol&0xf,0xf);
+      }
+      chan[i].volumeChanged=false;
+    }
+    if (chan[i].waveChanged) {
+      chWrite(i,0x6,chan[i].wavePos);
+      chan[i].freqChanged=true;
+      chan[i].waveChanged=false;
+    }
+    if (chan[i].waveUpdated) {
+      updateWaveCh(i);
+      if (!chan[i].keyOff) chan[i].keyOn=true;
+      chan[i].waveUpdated=false;
+    }
+    if (chan[i].freqChanged || chan[i].keyOn || chan[i].keyOff) {
+      chan[i].freq=parent->calcFreq((((chan[i].baseFreq*chan[i].waveLen)*(chanMax+1))/16),chan[i].pitch,false,0);
+      if (chan[i].freq<0) chan[i].freq=0;
+      if (chan[i].freq>0x3ffff) chan[i].freq=0x3ffff;
+      if (chan[i].keyOn) {
+        if (chan[i].wave<0) {
+          chan[i].wave=0;
+          if (chan[i].waveMode&0x2) {
+            updateWaveCh(i);
+          }
+        }
+      }
+      if (chan[i].keyOff && !isMuted[i]) {
+        chWriteMask(i,0x07,0,0xf);
+      }
+      chWrite(i,0x0,chan[i].freq&0xff);
+      chWrite(i,0x2,chan[i].freq>>8);
+      chWrite(i,0x4,((256-chan[i].waveLen)&0xfc)|((chan[i].freq>>16)&3));
+      if (chan[i].keyOn) chan[i].keyOn=false;
+      if (chan[i].keyOff) chan[i].keyOff=false;
+      chan[i].freqChanged=false;
+    }
+  }
+}
+
+int DivPlatformN163::dispatch(DivCommand c) {
+  switch (c.cmd) {
+    case DIV_CMD_NOTE_ON: {
+      DivInstrument* ins=parent->getIns(chan[c.chan].ins);
+      if (chan[c.chan].insChanged) {
+        chan[c.chan].wave=ins->n163.wave;
+        chan[c.chan].wavePos=ins->n163.wavePos;
+        chan[c.chan].waveLen=ins->n163.waveLen;
+        chan[c.chan].waveMode=ins->n163.waveMode;
+        chan[c.chan].waveChanged=true;
+        if (chan[c.chan].waveMode&0x3) {
+          chan[c.chan].waveUpdated=true;
+        }
+        chan[c.chan].insChanged=false;
+      }
+      if (c.value!=DIV_NOTE_NULL) {
+        chan[c.chan].baseFreq=NOTE_FREQUENCY(c.value);
+        chan[c.chan].freqChanged=true;
+        chan[c.chan].note=c.value;
+      }
+      chan[c.chan].active=true;
+      chan[c.chan].keyOn=true;
+      chan[c.chan].resVol=chan[c.chan].vol;
+      if (!isMuted[c.chan]) {
+        chan[c.chan].volumeChanged=true;
+      }
+      chan[c.chan].std.init(ins);
+      break;
+    }
+    case DIV_CMD_NOTE_OFF:
+      chan[c.chan].active=false;
+      chan[c.chan].keyOff=true;
+      chan[c.chan].keyOn=false;
+      //chan[c.chan].std.init(NULL);
+      break;
+    case DIV_CMD_NOTE_OFF_ENV:
+      chan[c.chan].active=false;
+      chan[c.chan].keyOff=true;
+      chan[c.chan].keyOn=false;
+      chan[c.chan].std.release();
+      break;
+    case DIV_CMD_ENV_RELEASE:
+      chan[c.chan].std.release();
+      break;
+    case DIV_CMD_INSTRUMENT:
+      if (chan[c.chan].ins!=c.value || c.value2==1) {
+        chan[c.chan].insChanged=true;
+        chan[c.chan].ins=c.value;
+      }
+      break;
+    case DIV_CMD_VOLUME:
+      if (chan[c.chan].vol!=c.value) {
+        chan[c.chan].vol=c.value;
+        if (!chan[c.chan].std.hasVol) {
+          chan[c.chan].outVol=c.value;
+          chan[c.chan].resVol=chan[c.chan].outVol;
+          if (!isMuted[c.chan]) {
+            chan[c.chan].volumeChanged=true;
+          }
+        }
+      }
+      break;
+    case DIV_CMD_GET_VOLUME:
+      return chan[c.chan].vol;
+      break;
+    case DIV_CMD_PITCH:
+      chan[c.chan].pitch=c.value;
+      chan[c.chan].freqChanged=true;
+      break;
+    case DIV_CMD_NOTE_PORTA: {
+      int destFreq=NOTE_FREQUENCY(c.value2);
+      bool return2=false;
+      if (destFreq>chan[c.chan].baseFreq) {
+        chan[c.chan].baseFreq+=c.value;
+        if (chan[c.chan].baseFreq>=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      } else {
+        chan[c.chan].baseFreq-=c.value;
+        if (chan[c.chan].baseFreq<=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      }
+      chan[c.chan].freqChanged=true;
+      if (return2) {
+        chan[c.chan].inPorta=false;
+        return 2;
+      }
+      break;
+    }
+    case DIV_CMD_WAVE:
+      chan[c.chan].wave=c.value;
+      if (chan[c.chan].waveMode&0x2) {
+        chan[c.chan].waveUpdated=true;
+      }
+      chan[c.chan].keyOn=true;
+      break;
+    case DIV_CMD_N163_WAVE_POSITION:
+      chan[c.chan].wavePos=c.value;
+      if (chan[c.chan].waveMode&0x2) {
+        chan[c.chan].waveUpdated=true;
+      }
+      chan[c.chan].waveChanged=true;
+      break;
+    case DIV_CMD_N163_WAVE_LENGTH:
+      chan[c.chan].waveLen=c.value&0xfc;
+      if (chan[c.chan].waveMode&0x2) {
+        chan[c.chan].waveUpdated=true;
+      }
+      chan[c.chan].freqChanged=true;
+      break;
+    case DIV_CMD_N163_WAVE_MODE:
+      chan[c.chan].waveMode=c.value&0x3;
+      if (chan[c.chan].waveMode&0x3) { // update now
+        chan[c.chan].waveUpdated=true;
+        chan[c.chan].waveChanged=true;
+      }
+      break;
+    case DIV_CMD_N163_WAVE_LOAD:
+      chan[c.chan].loadWave=c.value;
+      if (chan[c.chan].loadMode&0x2) { // load when every waveform changes
+        updateWave(chan[c.chan].loadWave,chan[c.chan].loadPos,chan[c.chan].loadLen);
+      }
+      break;
+    case DIV_CMD_N163_WAVE_LOADPOS:
+      chan[c.chan].loadPos=c.value;
+      break;
+    case DIV_CMD_N163_WAVE_LOADLEN:
+      chan[c.chan].loadLen=c.value&0xfc;
+      break;
+    case DIV_CMD_N163_WAVE_LOADMODE:
+      chan[c.chan].loadMode=c.value&0x3;
+      if (chan[c.chan].loadMode&0x1) { // load now
+        updateWave(chan[c.chan].loadWave,chan[c.chan].loadPos,chan[c.chan].loadLen);
+      }
+      break;
+    case DIV_CMD_N163_GLOBAL_WAVE_LOAD:
+      loadWave=c.value;
+      if (loadMode&0x2) { // load when every waveform changes
+        updateWave(loadWave,loadPos,loadLen);
+      }
+      break;
+    case DIV_CMD_N163_GLOBAL_WAVE_LOADPOS:
+      loadPos=c.value;
+      break;
+    case DIV_CMD_N163_GLOBAL_WAVE_LOADLEN:
+      loadLen=c.value&0xfc;
+      break;
+    case DIV_CMD_N163_GLOBAL_WAVE_LOADMODE:
+      loadMode=c.value&0x3;
+      if (loadMode&0x3) { // load now
+        updateWave(loadWave,loadPos,loadLen);
+      }
+      break;
+    case DIV_CMD_N163_CHANNEL_LIMIT:
+      if (chanMax!=(c.value&0x7)) {
+        chanMax=c.value&0x7;
+        rWriteMask(0x7f,chanMax<<4,0x70);
+        forceIns();
+      }
+      break;
+    case DIV_CMD_LEGATO:
+      chan[c.chan].baseFreq=NOTE_FREQUENCY(c.value+((chan[c.chan].std.willArp && !chan[c.chan].std.arpMode)?(chan[c.chan].std.arp):(0)));
+      chan[c.chan].freqChanged=true;
+      chan[c.chan].note=c.value;
+      break;
+    case DIV_CMD_PRE_PORTA:
+      if (chan[c.chan].active && c.value2) {
+        if (parent->song.resetMacroOnPorta) {
+          chan[c.chan].std.init(parent->getIns(chan[c.chan].ins));
+          chan[c.chan].keyOn=true;
+        }
+      }
+      chan[c.chan].inPorta=c.value;
+      break;
+    case DIV_CMD_GET_VOLMAX:
+      return 15;
+      break;
+    case DIV_ALWAYS_SET_VOLUME:
+      return 1;
+      break;
+    default:
+      break;
+  }
+  return 1;
+}
+
+void DivPlatformN163::muteChannel(int ch, bool mute) {
+  isMuted[ch]=mute;
+  chan[ch].volumeChanged=true;
+}
+
+void DivPlatformN163::forceIns() {
+  for (int i=0; i<=chanMax; i++) {
+    chan[i].insChanged=true;
+    if (chan[i].active) {
+      chan[i].keyOn=true;
+      chan[i].freqChanged=true;
+      chan[i].volumeChanged=true;
+      chan[i].waveChanged=true;
+      if (chan[i].waveMode&0x2) {
+        chan[i].waveUpdated=true;
+      }
+    }
+  }
+}
+
+void DivPlatformN163::notifyWaveChange(int wave) {
+  for (int i=0; i<8; i++) {
+    if (chan[i].wave==wave) {
+      if (chan[i].waveMode&0x2) {
+        chan[i].waveUpdated=true;
+      }
+    }
+  }
+}
+
+void DivPlatformN163::notifyInsChange(int ins) {
+  for (int i=0; i<8; i++) {
+    if (chan[i].ins==ins) {
+      chan[i].insChanged=true;
+    }
+  }
+}
+
+void DivPlatformN163::notifyInsDeletion(void* ins) {
+  for (int i=0; i<8; i++) {
+    chan[i].std.notifyInsDeletion((DivInstrument*)ins);
+  }
+}
+
+void* DivPlatformN163::getChanState(int ch) {
+  return &chan[ch];
+}
+
+unsigned char* DivPlatformN163::getRegisterPool() {
+  for (int i=0; i<128; i++) {
+    regPool[i]=n163->reg(i);
+  }
+  return regPool;
+}
+
+int DivPlatformN163::getRegisterPoolSize() {
+  return 128;
+}
+
+void DivPlatformN163::reset() {
+  while (!writes.empty()) writes.pop();
+  for (int i=0; i<8; i++) {
+    chan[i]=DivPlatformN163::Channel();
+  }
+
+  n163->reset();
+  memset(regPool,0,128);
+
+  n163->set_disable(false);
+  rWrite(0x7f,chanMax<<4);
+  loadWave=-1;
+  loadPos=0;
+  loadLen=0;
+  loadMode=0;
+}
+
+void DivPlatformN163::poke(unsigned int addr, unsigned short val) {
+  rWrite(addr,val);
+}
+
+void DivPlatformN163::poke(std::vector<DivRegWrite>& wlist) {
+  for (DivRegWrite& i: wlist) rWrite(i.addr,i.val);
+}
+
+void DivPlatformN163::setFlags(unsigned int flags) {
+  switch (flags&0xf) {
+    case 0x0: // NTSC
+      rate=COLOR_NTSC/2.0;
+      break;
+    case 0x1: // PAL
+      rate=COLOR_PAL*3.0/8.0;
+      break;
+    case 0x2: // Dendy
+      rate=COLOR_PAL*2.0/5.0;
+      break;
+  }
+  chanMax=(flags>>4)&7;
+  chipClock=rate;
+  rate/=15;
+}
+
+int DivPlatformN163::init(DivEngine* p, int channels, int sugRate, unsigned int flags) {
+  parent=p;
+  dumpWrites=false;
+  skipRegisterWrites=false;
+  for (int i=0; i<8; i++) {
+    isMuted[i]=false;
+  }
+  n163=new n163_core();
+  setFlags(flags);
+
+  reset();
+
+  return 8;
+}
+
+void DivPlatformN163::quit() {
+  delete n163;
+}
+
+DivPlatformN163::~DivPlatformN163() {
+}
--- a/src/engine/platform/n163.h
+++ b/src/engine/platform/n163.h
@ -0,0 +1,107 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2022 tildearrow and contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef _N163_H
+#define _N163_H
+
+#include "../dispatch.h"
+#include <queue>
+#include "../macroInt.h"
+#include "sound/n163/n163.hpp"
+
+class DivPlatformN163: public DivDispatch {
+  struct Channel {
+    int freq, baseFreq, pitch, note;
+    short ins, wave, wavePos, waveLen;
+    unsigned char waveMode;
+    short loadWave, loadPos, loadLen;
+    unsigned char loadMode;
+    bool active, insChanged, freqChanged, volumeChanged, waveChanged, waveUpdated, keyOn, keyOff, inPorta;
+    signed char vol, outVol, resVol;
+    DivMacroInt std;
+    Channel():
+      freq(0),
+      baseFreq(0),
+      pitch(0),
+      note(0),
+      ins(-1),
+      wave(-1),
+      wavePos(0),
+      waveLen(0),
+      waveMode(0),
+      loadWave(-1),
+      loadPos(0),
+      loadLen(0),
+      loadMode(0),
+      active(false),
+      insChanged(true),
+      freqChanged(false),
+      volumeChanged(false),
+      waveChanged(false),
+      waveUpdated(false),
+      keyOn(false),
+      keyOff(false),
+      inPorta(false),
+      vol(15),
+      outVol(15),
+      resVol(15) {}
+  };
+  Channel chan[8];
+  bool isMuted[8];
+  struct QueuedWrite {
+      unsigned char addr;
+      unsigned char val;
+      unsigned char mask;
+      QueuedWrite(unsigned char a, unsigned char v, unsigned char m=~0): addr(a), val(v), mask(m) {}
+  };
+  std::queue<QueuedWrite> writes;
+  unsigned char chanMax;
+  short loadWave, loadPos, loadLen;
+  unsigned char loadMode;
+
+  n163_core *n163;
+  unsigned char regPool[128];
+  void updateWave(int wave, int pos, int len);
+  void updateWaveCh(int ch);
+  friend void putDispatchChan(void*,int,int);
+
+  public:
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
+    int dispatch(DivCommand c);
+    void* getChanState(int chan);
+    unsigned char* getRegisterPool();
+    int getRegisterPoolSize();
+    void reset();
+    void forceIns();
+    void tick();
+    void muteChannel(int ch, bool mute);
+    void setFlags(unsigned int flags);
+    void notifyWaveChange(int wave);
+    void notifyInsChange(int ins);
+    void notifyInsDeletion(void* ins);
+    void poke(unsigned int addr, unsigned short val);
+    void poke(std::vector<DivRegWrite>& wlist);
+    const char** getRegisterSheet();
+    const char* getEffectName(unsigned char effect);
+    int init(DivEngine* parent, int channels, int sugRate, unsigned int flags);
+    void quit();
+    ~DivPlatformN163();
+};
+
+#endif
--- a/src/engine/platform/opll.cpp
+++ b/src/engine/platform/opll.cpp
@ -651,6 +651,7 @@ int DivPlatformOPLL::dispatch(DivCommand c) {

 void DivPlatformOPLL::forceIns() {
  for (int i=0; i<9; i++) {
+    if (i>=6 && properDrums) continue;
    // update custom preset
    if (chan[i].state.opllPreset==0 && i==lastCustomMemory) {
      DivInstrumentFM::Operator& mod=chan[i].state.op[0];
@ -675,7 +676,7 @@ void DivPlatformOPLL::forceIns() {
      }
    }
  }
-  if (drums) {
+  if (drums) { // WHAT?! FIX THIS!
    immWrite(0x16,0x20);
    immWrite(0x26,0x05);
    immWrite(0x16,0x20);
@ -687,6 +688,12 @@ void DivPlatformOPLL::forceIns() {
    immWrite(0x18,0xC0);
    immWrite(0x28,0x01);
  }
+  // restore drum volumes
+  if (properDrums) {
+    rWrite(0x36,drumVol[0]);
+    rWrite(0x37,drumVol[1]|(drumVol[4]<<4));
+    rWrite(0x38,drumVol[3]|(drumVol[2]<<4));
+  }
  drumState=0;
 }

--- a/src/engine/platform/sms.cpp
+++ b/src/engine/platform/sms.cpp
@ -57,7 +57,10 @@ void DivPlatformSMS::tick() {
  for (int i=0; i<4; i++) {
    chan[i].std.next();
    if (chan[i].std.hadVol) {
-      chan[i].outVol=((chan[i].vol&15)*MIN(15,chan[i].std.vol))>>4;
+      chan[i].outVol=MIN(15,chan[i].std.vol)-(15-(chan[i].vol&15));
+      if (chan[i].outVol<0) chan[i].outVol=0;
+      // old formula
+      // ((chan[i].vol&15)*MIN(15,chan[i].std.vol))>>4;
      rWrite(0x90|(i<<5)|(isMuted[i]?15:(15-(chan[i].outVol&15))));
    }
    if (chan[i].std.hadArp) {
@ -66,8 +69,11 @@ void DivPlatformSMS::tick() {
          chan[i].baseFreq=NOTE_PERIODIC(chan[i].std.arp);
          chan[i].actualNote=chan[i].std.arp;
        } else {
-          chan[i].baseFreq=NOTE_PERIODIC(chan[i].note+chan[i].std.arp);
-          chan[i].actualNote=chan[i].note+chan[i].std.arp;
+          // TODO: check whether this weird octave boundary thing applies to other systems as well
+          int areYouSerious=chan[i].note+chan[i].std.arp;
+          while (areYouSerious>0x60) areYouSerious-=12;
+          chan[i].baseFreq=NOTE_PERIODIC(areYouSerious);
+          chan[i].actualNote=areYouSerious;
        }
        chan[i].freqChanged=true;
      }
@ -93,10 +99,11 @@ void DivPlatformSMS::tick() {
      if (chan[i].actualNote>0x5d) chan[i].freq=0x01;
      rWrite(0x80|i<<5|(chan[i].freq&15));
      rWrite(chan[i].freq>>4);
-      if (i==2 && snNoiseMode&2) {
+      // what?
+      /*if (i==2 && snNoiseMode&2) {
        chan[3].baseFreq=chan[2].baseFreq;
        chan[3].actualNote=chan[2].actualNote;
-      }
+      }*/
      chan[i].freqChanged=false;
    }
  }
--- a/src/engine/platform/sound/n163/n163.cpp
+++ b/src/engine/platform/sound/n163/n163.cpp
@ -0,0 +1,137 @@
+/*
+	License: BSD-3-Clause
+	see https://github.com/cam900/vgsound_emu/LICENSE for more details
+
+	Copyright holder(s): cam900
+	Namco 163 Sound emulation core
+
+	This chip is one of NES mapper with sound expansion, This one is by Namco.
+
+	It has 1 to 8 wavetable channels, All channel registers and waveforms are stored to internal RAM.
+	4 bit Waveforms are freely allocatable, and its length is variables; its can be stores many short waveforms or few long waveforms in RAM.
+
+	But waveforms are needs to squash, reallocate to avoid conflict with channel register area, each channel register size is 8 bytes per channels.
+
+	Sound output is time division multiplexed, it's can be captured only single channels output at once. in reason, More activated channels are less sound quality.
+
+	Sound register layout
+
+	Address Bit      Description
+	        7654 3210
+
+	78-7f Channel 0
+	78      xxxx xxxx Channel 0 Pitch input bit 0-7
+	79      xxxx xxxx Channel 0 Accumulator bit 0-7*
+	7a      xxxx xxxx Channel 0 Pitch input bit 8-15
+	7b      xxxx xxxx Channel 0 Accumulator bit 8-15*
+	7c      xxxx xx-- Channel 0 Waveform length, 256 - (x * 4)
+	        ---- --xx Channel 0 Pitch input bit 16-17
+	7d      xxxx xxxx Channel 0 Accumulator bit 16-23*
+	7e      xxxx xxxx Channel 0 Waveform base offset
+	        xxxx xxx- RAM byte (0 to 127)
+	        ---- ---x RAM nibble
+	        ---- ---0 Low nibble
+	        ---- ---1 High nibble
+	7f      ---- xxxx Channel 0 Volume
+
+	7f Number of active channels
+	7f      -xxx ---- Number of active channels
+	        -000 ---- Channel 0 activated
+	        -001 ---- Channel 1 activated
+	        -010 ---- Channel 2 activated
+	        ...
+	        -110 ---- Channel 6 activated
+	        -111 ---- Channel 7 activated
+
+	70-77 Channel 1 (Optional if activated)
+	68-6f Channel 2 (Optional if activated)
+	...
+	48-4f Channel 6 (Optional if activated)
+	40-47 Channel 7 (Optional if activated)
+
+	Rest of RAM area are for 4 bit Waveform and/or scratchpad.
+	Each waveform byte has 2 nibbles packed, fetches LSB first, MSB next.
+	        ---- xxxx 4 bit waveform, LSB
+	        xxxx ---- Same as above, MSB
+
+	Waveform address: Waveform base offset + Bit 16 to 23 of Accumulator, 1 LSB of result is nibble select, 7 MSB of result is Byte address in RAM.
+
+	Frequency formula:
+	Frequency: Pitch input * ((Input clock * 15 * Number of activated voices) / 65536)
+*/
+
+#include "n163.hpp"
+
+void n163_core::tick()
+{
+	m_out = 0;
+	// 0xe000-0xe7ff Disable sound bits (bit 6, bit 0 to 5 are CPU ROM Bank 0x8000-0x9fff select.)
+	if (m_disable)
+		return;
+
+	// tick per each clock
+	const u32 freq = m_ram[m_voice_cycle + 0] | (u32(m_ram[m_voice_cycle + 2]) << 8) | (bitfield<u32>(m_ram[m_voice_cycle + 4], 0, 2) << 16); // 18 bit frequency
+	u32 accum      = m_ram[m_voice_cycle + 1] | (u32(m_ram[m_voice_cycle + 3]) << 8) | (          u32(m_ram[m_voice_cycle + 5])       << 16); // 24 bit accumulator
+	const u16 length = 256 - (m_ram[m_voice_cycle + 4] & 0xfc);
+	const u8 addr    = m_ram[m_voice_cycle + 6] + bitfield(accum, 16, 8);
+	const s16 wave   = (bitfield(m_ram[bitfield(addr, 1, 7)], bitfield(addr, 0) << 2, 4) - 8);
+	const s16 volume = bitfield(m_ram[m_voice_cycle + 7], 0, 4);
+
+	// accumulate address
+	accum = bitfield(accum + freq, 0, 24);
+	if (bitfield(accum, 16, 8) >= length)
+		accum = bitfield(accum, 0, 18);
+
+	// writeback to register
+	m_ram[m_voice_cycle + 1] = bitfield(accum,  0, 8);
+	m_ram[m_voice_cycle + 3] = bitfield(accum,  8, 8);
+	m_ram[m_voice_cycle + 5] = bitfield(accum, 16, 8);
+
+	// update voice cycle
+	m_voice_cycle -= 0x8;
+	if (m_voice_cycle < (0x78 - (bitfield(m_ram[0x7f], 4, 3) << 3)))
+		m_voice_cycle = 0x78;
+
+	// output 4 bit waveform and volume, multiplexed
+	m_out = wave * volume;
+}
+
+void n163_core::reset()
+{
+	// reset this chip
+	m_disable = false;
+	std::fill(std::begin(m_ram), std::end(m_ram), 0);
+	m_voice_cycle = 0x78;
+	m_addr_latch.reset();
+	m_out = 0;
+}
+
+// accessor
+void n163_core::addr_w(u8 data)
+{
+	// 0xf800-0xffff Sound address, increment
+	m_addr_latch.addr = bitfield(data, 0, 7);
+	m_addr_latch.incr = bitfield(data, 7);
+}
+
+void n163_core::data_w(u8 data, bool cpu_access)
+{
+	// 0x4800-0x4fff Sound data write
+	m_ram[m_addr_latch.addr] = data;
+
+	// address latch increment
+	if (cpu_access && m_addr_latch.incr)
+		m_addr_latch.addr = bitfield(m_addr_latch.addr + 1, 0, 7);
+}
+
+u8 n163_core::data_r(bool cpu_access)
+{
+	// 0x4800-0x4fff Sound data read
+	const u8 ret = m_ram[m_addr_latch.addr];
+
+	// address latch increment
+	if (cpu_access && m_addr_latch.incr)
+		m_addr_latch.addr = bitfield(m_addr_latch.addr + 1, 0, 7);
+
+	return ret;
+}
--- a/src/engine/platform/sound/n163/n163.hpp
+++ b/src/engine/platform/sound/n163/n163.hpp
@ -0,0 +1,78 @@
+/*
+	License: BSD-3-Clause
+	see https://github.com/cam900/vgsound_emu/LICENSE for more details
+
+	Copyright holder(s): cam900
+	Namco 163 Sound emulation core
+*/
+
+#include <algorithm>
+#include <memory>
+
+#ifndef _VGSOUND_EMU_N163_HPP
+#define _VGSOUND_EMU_N163_HPP
+
+#pragma once
+
+namespace n163
+{
+	typedef unsigned char       u8;
+	typedef unsigned short     u16;
+	typedef unsigned int       u32;
+	typedef signed short       s16;
+
+	// get bitfield, bitfield(input, position, len)
+	template<typename T> T bitfield(T in, u8 pos, u8 len = 1)
+	{
+		return (in >> pos) & (len ? (T(1 << len) - 1) : 1);
+	}
+};
+
+using namespace n163;
+class n163_core
+{
+public:
+	// accessors, getters, setters
+	void addr_w(u8 data);
+	void data_w(u8 data, bool cpu_access = false);
+	u8 data_r(bool cpu_access = false);
+
+	void set_disable(bool disable) { m_disable = disable; }
+
+	// internal state
+	void reset();
+	void tick();
+
+	// sound output pin
+	s16 out() { return m_out; }
+
+	// register pool
+	u8 reg(u8 addr) { return m_ram[addr & 0x7f]; }
+
+private:
+	// Address latch
+	struct addr_latch_t
+	{
+		addr_latch_t()
+			: addr(0)
+			, incr(0)
+		{ };
+
+		void reset()
+		{
+			addr = 0;
+			incr = 0;
+		}
+
+		u8 addr : 7;
+		u8 incr : 1;
+	};
+
+	bool m_disable = false;
+	u8 m_ram[0x80] = {0}; // internal 128 byte RAM
+	u8 m_voice_cycle = 0x78; // Voice cycle for processing
+	addr_latch_t m_addr_latch; // address latch
+	s16 m_out = 0; // output
+};
+
+#endif
--- a/src/engine/platform/sound/vrcvi/vrcvi.cpp
+++ b/src/engine/platform/sound/vrcvi/vrcvi.cpp
@ -0,0 +1,313 @@
+/*
+	License: BSD-3-Clause
+	see https://github.com/cam900/vgsound_emu/LICENSE for more details
+
+	Copyright holder(s): cam900
+	Konami VRC VI sound emulation core
+
+	It's one of NES mapper with built-in sound chip, and also one of 2 Konami VRCs with this feature. (rest one has OPLL derivatives.)
+
+	It's also DACless like other sound chip and mapper-with-sound manufactured by konami,
+	the Chips 6 bit digital sound output is needs converted to analog sound output when you it want to make some sounds, or send to sound mixer.
+
+	Its are used for Akumajou Densetsu (Japan release of Castlevania III), Madara, Esper Dream 2.
+
+	The chip is installed in 351951 PCB and 351949A PCB.
+
+	351951 PCB is used exclusivly for Akumajou Densetsu, Small board has VRC VI, PRG and CHR ROM.
+	- It's configuration also calls VRC6a, iNES mapper 024.
+
+	351949A PCB is for Last 2 titles with VRC VI, Bigger board has VRC VI, PRG and CHR ROM, and Battery Backed 8K x 8 bit SRAM.
+	- Additionally, It's PRG A0 and A1 bit to VRC VI input is swapped, compare to above.
+	- It's configuration also calls VRC6b, iNES mapper 026.
+
+	The chip itself has 053328, 053329, 053330 Revision, but Its difference between revision is unknown.
+
+	Like other mappers for NES, It has internal timer - Its timer can be sync with scanline like other Konami mapper in this era.
+
+	Register layout (Sound and Timer only; 351951 PCB case, 351949A swaps xxx1 and xxx2):
+
+	Address Bits      Description
+	        7654 3210
+
+	9000-9002 Pulse 1
+
+	9000    x--- ---- Pulse 1 Duty ignore
+	        -xxx ---- Pulse 1 Duty cycle
+	        ---- xxxx Pulse 1 Volume
+	9001    xxxx xxxx Pulse 1 Pitch bit 0-7
+	9002    x--- ---- Pulse 1 Enable
+	        ---- xxxx Pulse 1 Pitch bit 8-11
+
+	9003 Sound control
+
+	9003    ---- -x-- 4 bit Frequency mode
+	        ---- -0x- 8 bit Frequency mode
+	        ---- ---x Halt
+
+	a000-a002 Pulse 2
+
+	a000    x--- ---- Pulse 2 Duty ignore
+	        -xxx ---- Pulse 2 Duty cycle
+	        ---- xxxx Pulse 2 Volume
+	a001    xxxx xxxx Pulse 2 Pitch bit 0-7
+	a002    x--- ---- Pulse 2 Enable
+	        ---- xxxx Pulse 2 Pitch bit 8-11
+
+	b000-b002 Sawtooth
+
+	b000    --xx xxxx Sawtooth Accumulate Rate
+	b001    xxxx xxxx Sawtooth Pitch bit 0-7
+	b002    x--- ---- Sawtooth Enable
+	        ---- xxxx Sawtooth Pitch bit 8-11
+
+	f000-f002 IRQ Timer
+
+	f000    xxxx xxxx IRQ Timer latch
+	f001    ---- -0-- Sync with scanline
+	        ---- --x- Enable timer
+	        ---- ---x Enable timer after IRQ Acknowledge
+	f002    ---- ---- IRQ Acknowledge
+
+	Frequency calculations:
+
+	if 4 bit Frequency Mode then
+		Frequency: Input clock / (bit 8 to 11 of Pitch + 1)
+	end else if 8 bit Frequency Mode then
+		Frequency: Input clock / (bit 4 to 11 of Pitch + 1)
+	end else then
+		Frequency: Input clock / (Pitch + 1)
+	end
+*/
+
+#include "vrcvi.hpp"
+
+void vrcvi_core::tick()
+{
+	m_out = 0;
+	if (!m_control.m_halt) // Halt flag
+	{
+		// tick per each clock
+		for (auto & elem : m_pulse)
+		{
+			if (elem.tick())
+				m_out += elem.m_control.m_volume; // add 4 bit pulse output
+		}
+		if (m_sawtooth.tick())
+			m_out += bitfield(m_sawtooth.m_accum, 3, 5); // add 5 bit sawtooth output
+	}
+	if (m_timer.tick())
+		m_timer.counter_tick();
+}
+
+void vrcvi_core::reset()
+{
+	for (auto & elem : m_pulse)
+		elem.reset();
+
+	m_sawtooth.reset();
+	m_timer.reset();
+	m_control.reset();
+	m_out = 0;
+}
+
+bool vrcvi_core::alu_t::tick()
+{
+	if (m_divider.m_enable)
+	{
+		const u16 temp = m_counter;
+		// post decrement
+		if (bitfield(m_host.m_control.m_shift, 1))
+		{
+			m_counter = (m_counter & 0x0ff) | (bitfield(bitfield(m_counter, 8, 4) - 1, 0, 4) << 8);
+			m_counter = (m_counter & 0xf00) | (bitfield(bitfield(m_counter, 0, 8) - 1, 0, 8) << 0);
+		}
+		else if (bitfield(m_host.m_control.m_shift, 0))
+		{
+			m_counter = (m_counter & 0x00f) | (bitfield(bitfield(m_counter, 4, 8) - 1, 0, 8) << 4);
+			m_counter = (m_counter & 0xff0) | (bitfield(bitfield(m_counter, 0, 4) - 1, 0, 4) << 0);
+		}
+		else
+			m_counter = bitfield(bitfield(m_counter, 0, 12) - 1, 0, 12);
+
+		// carry handling
+		bool carry = bitfield(m_host.m_control.m_shift, 1) ? (bitfield(temp, 8, 4) == 0) : 
+		            (bitfield(m_host.m_control.m_shift, 0) ? (bitfield(temp, 4, 8) == 0) :
+								(bitfield(temp, 0, 12) == 0));
+		if (carry)
+			m_counter = m_divider.m_divider;
+
+		return carry;
+	}
+	return false;
+}
+
+bool vrcvi_core::pulse_t::tick()
+{
+	if (!m_divider.m_enable)
+	{
+		m_cycle = 0;
+		return false;
+	}
+
+	if (vrcvi_core::alu_t::tick())
+		m_cycle = bitfield(m_cycle + 1, 0, 4);
+
+	return m_control.m_mode ? true : ((m_cycle > m_control.m_duty) ? true : false);
+}
+
+bool vrcvi_core::sawtooth_t::tick()
+{
+	if (!m_divider.m_enable)
+	{
+		m_accum = 0;
+		return false;
+	}
+
+	if (vrcvi_core::alu_t::tick())
+	{
+		if (bitfield(m_cycle++, 0)) // Even step only
+			m_accum += m_rate;
+		if (m_cycle >= 14) // Reset accumulator at every 14 cycles
+		{
+			m_accum = 0;
+			m_cycle = 0;
+		}
+	}
+	return (m_accum == 0) ? false : true;
+}
+
+void vrcvi_core::alu_t::reset()
+{
+	m_divider.reset();
+	m_counter = 0;
+	m_cycle = 0;
+}
+
+void vrcvi_core::pulse_t::reset()
+{
+	vrcvi_core::alu_t::reset();
+	m_control.reset();
+}
+
+void vrcvi_core::sawtooth_t::reset()
+{
+	vrcvi_core::alu_t::reset();
+	m_rate = 0;
+	m_accum = 0;
+}
+
+bool vrcvi_core::timer_t::tick()
+{
+	if (m_timer_control.m_enable)
+	{
+		if (!m_timer_control.m_sync) // scanline sync mode
+		{
+			m_prescaler -= 3;
+			if (m_prescaler <= 0)
+			{
+				m_prescaler += 341;
+				return true;
+			}
+		}
+	}
+	return (m_timer_control.m_enable && m_timer_control.m_sync) ? true : false;
+}
+
+void vrcvi_core::timer_t::counter_tick()
+{
+	if (bitfield(++m_counter, 0, 8) == 0)
+	{
+		m_counter = m_counter_latch;
+		irq_set();
+	}
+}
+
+void vrcvi_core::timer_t::reset()
+{
+	m_timer_control.reset();
+	m_prescaler = 341;
+	m_counter = m_counter_latch = 0;
+	irq_clear();
+}
+
+// Accessors
+
+void vrcvi_core::alu_t::divider_t::write(bool msb, u8 data)
+{
+	if (msb)
+	{
+		m_divider = (m_divider & ~0xf00) | (bitfield<u32>(data, 0, 4) << 8);
+		m_enable = bitfield(data, 7);
+	}
+	else
+		m_divider = (m_divider & ~0x0ff) | data;
+}
+
+
+void vrcvi_core::pulse_w(u8 voice, u8 address, u8 data)
+{
+	pulse_t &v = m_pulse[voice];
+	switch (address)
+	{
+		case 0x00: // Control - 0x9000 (Pulse 1), 0xa000 (Pulse 2)
+			v.m_control.m_mode = bitfield(data, 7);
+			v.m_control.m_duty = bitfield(data, 4, 3);
+			v.m_control.m_volume = bitfield(data, 0, 4);
+			break;
+		case 0x01: // Pitch LSB - 0x9001/0x9002 (Pulse 1), 0xa001/0xa002 (Pulse 2)
+			v.m_divider.write(false, data);
+			break;
+		case 0x02: // Pitch MSB, Enable/Disable - 0x9002/0x9001 (Pulse 1), 0xa002/0xa001 (Pulse 2)
+			v.m_divider.write(true, data);
+			break;
+	}
+}
+
+void vrcvi_core::saw_w(u8 address, u8 data)
+{
+	switch (address)
+	{
+		case 0x00: // Sawtooth Accumulate - 0xb000
+			m_sawtooth.m_rate = bitfield(data, 0, 6);
+			break;
+		case 0x01: // Pitch LSB - 0xb001/0xb002 (Sawtooth)
+			m_sawtooth.m_divider.write(false, data);
+			break;
+		case 0x02: // Pitch MSB, Enable/Disable - 0xb002/0xb001 (Sawtooth)
+			m_sawtooth.m_divider.write(true, data);
+			break;
+	}
+}
+
+void vrcvi_core::timer_w(u8 address, u8 data)
+{
+	switch (address)
+	{
+		case 0x00: // Timer latch - 0xf000
+			m_timer.m_counter_latch = data;
+			break;
+		case 0x01: // Timer control - 0xf001/0xf002
+			m_timer.m_timer_control.m_sync = bitfield(data, 2);
+			m_timer.m_timer_control.m_enable = bitfield(data, 1);
+			m_timer.m_timer_control.m_enable_ack = bitfield(data, 0);
+			if (m_timer.m_timer_control.m_enable)
+			{
+				m_timer.m_counter = m_timer.m_counter_latch;
+				m_timer.m_prescaler = 341;
+			}
+			m_timer.irq_clear();
+			break;
+		case 0x02: // IRQ Acknowledge - 0xf002/0xf001
+			m_timer.irq_clear();
+			m_timer.m_timer_control.m_enable = m_timer.m_timer_control.m_enable_ack;
+			break;
+	}
+}
+
+void vrcvi_core::control_w(u8 data)
+{
+	// Global control - 0x9003
+	m_control.m_halt = bitfield(data, 0);
+	m_control.m_shift = bitfield(data, 1, 2);
+}
--- a/src/engine/platform/sound/vrcvi/vrcvi.hpp
+++ b/src/engine/platform/sound/vrcvi/vrcvi.hpp
@ -0,0 +1,238 @@
+/*
+	License: BSD-3-Clause
+	see https://github.com/cam900/vgsound_emu/LICENSE for more details
+
+	Copyright holder(s): cam900
+	Konami VRC VI sound emulation core
+
+	See vrcvi.cpp to more infos.
+*/
+
+#include <algorithm>
+#include <memory>
+
+#ifndef _VGSOUND_EMU_VRCVI_HPP
+#define _VGSOUND_EMU_VRCVI_HPP
+
+#pragma once
+
+namespace vrcvi
+{
+	typedef unsigned char       u8;
+	typedef unsigned short     u16;
+	typedef unsigned int       u32;
+	typedef signed char         s8;
+	typedef signed short       s16;
+
+	// get bitfield, bitfield(input, position, len)
+	template<typename T> T bitfield(T in, u8 pos, u8 len = 1)
+	{
+		return (in >> pos) & (len ? (T(1 << len) - 1) : 1);
+	}
+};
+
+class vrcvi_intf
+{
+public:
+	virtual void irq_w(bool irq) { }
+};
+
+using namespace vrcvi;
+class vrcvi_core
+{
+public:
+	friend class vrcvi_intf;
+	// constructor
+	vrcvi_core(vrcvi_intf &intf)
+		: m_pulse{*this,*this}
+		, m_sawtooth(*this)
+		, m_timer(*this)
+		, m_intf(intf)
+	{
+	}
+	// accessors, getters, setters
+	void pulse_w(u8 voice, u8 address, u8 data);
+	void saw_w(u8 address, u8 data);
+	void timer_w(u8 address, u8 data);
+	void control_w(u8 data);
+
+	// internal state
+	void reset();
+	void tick();
+
+	// 6 bit output
+	s8 out() { return m_out; }
+private:
+	// Common ALU for sound channels
+	struct alu_t
+	{
+		alu_t(vrcvi_core &host)
+			: m_host(host)
+		{ };
+
+
+		virtual void reset();
+		virtual bool tick();
+
+		struct divider_t
+		{
+			divider_t()
+				: m_divider(0)
+				, m_enable(0)
+			{ };
+
+			void reset()
+			{
+				m_divider = 0;
+				m_enable = 0;
+			}
+
+			void write(bool msb, u8 data);
+
+			u16 m_divider : 12; // divider (pitch)
+			u16 m_enable  : 1;   // channel enable flag
+		};
+
+		vrcvi_core &m_host;
+		divider_t m_divider;
+		u16 m_counter = 0; // clock counter
+		u8 m_cycle = 0;    // clock cycle
+	};
+
+	// 2 Pulse channels
+	struct pulse_t : alu_t
+	{
+		pulse_t(vrcvi_core &host)
+			: alu_t(host)
+		{ };
+
+		virtual void reset() override;
+		virtual bool tick() override;
+
+		// Control bits
+		struct pulse_control_t
+		{
+			pulse_control_t()
+				: m_mode(0)
+				, m_duty(0)
+				, m_volume(0)
+			{ };
+
+			void reset()
+			{
+				m_mode = 0;
+				m_duty = 0;
+				m_volume = 0;
+			}
+
+			u8 m_mode   : 1; // duty toggle flag
+			u8 m_duty   : 3; // 3 bit duty cycle
+			u8 m_volume : 4; // 4 bit volume
+		};
+
+		pulse_control_t m_control;
+	};
+
+	// 1 Sawtooth channel
+	struct sawtooth_t : alu_t
+	{
+		sawtooth_t(vrcvi_core &host)
+			: alu_t(host)
+		{ };
+
+		virtual void reset() override;
+		virtual bool tick() override;
+
+		u8 m_rate = 0;  // sawtooth accumulate rate
+		u8 m_accum = 0; // sawtooth accumulator, high 5 bit is accumulated to output
+	};
+
+	// Internal timer
+	struct timer_t
+	{
+		timer_t(vrcvi_core &host)
+			: m_host(host)
+		{ };
+
+		void reset();
+		bool tick();
+		void counter_tick();
+
+		// IRQ update
+		void update() { m_host.m_intf.irq_w(m_timer_control.m_irq_trigger); }
+		void irq_set()
+		{
+			if (!m_timer_control.m_irq_trigger)
+			{
+				m_timer_control.m_irq_trigger = 1;
+				update();
+			}
+		}
+		void irq_clear()
+		{
+			if (m_timer_control.m_irq_trigger)
+			{
+				m_timer_control.m_irq_trigger = 0;
+				update();
+			}
+		}
+
+		// Control bits
+		struct timer_control_t
+		{
+			timer_control_t()
+				: m_irq_trigger(0)
+				, m_enable_ack(0)
+				, m_enable(0)
+				, m_sync(0)
+			{ };
+
+			void reset()
+			{
+				m_irq_trigger = 0;
+				m_enable_ack = 0;
+				m_enable = 0;
+				m_sync = 0;
+			}
+
+			u8 m_irq_trigger : 1;
+			u8 m_enable_ack : 1;
+			u8 m_enable : 1;
+			u8 m_sync : 1;
+		};
+
+		vrcvi_core &m_host;              // host core
+		timer_control_t m_timer_control; // timer control bits
+		s16 m_prescaler = 341;           // prescaler
+		u8 m_counter = 0;                // clock counter
+		u8 m_counter_latch = 0;          // clock counter latch
+	};
+
+	struct global_control_t
+	{
+		global_control_t()
+			: m_halt(0)
+			, m_shift(0)
+		{ };
+
+		void reset()
+		{
+			m_halt = 0;
+			m_shift = 0;
+		}
+
+		u8 m_halt  : 1; // halt sound
+		u8 m_shift : 2; // 4/8 bit right shift
+	};
+
+	pulse_t m_pulse[2];         // 2 pulse channels
+	sawtooth_t m_sawtooth;      // sawtooth channel
+	timer_t m_timer;            // internal timer
+	global_control_t m_control; // control
+
+	vrcvi_intf &m_intf;
+
+	s8 m_out = 0; // 6 bit output
+};
+
+#endif
--- a/src/engine/platform/vic20.cpp
+++ b/src/engine/platform/vic20.cpp
@ -121,8 +121,11 @@ void DivPlatformVIC20::tick() {
    }
    if (chan[i].freqChanged || chan[i].keyOn || chan[i].keyOff) {
      chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,true);
-      if (i<3) chan[i].freq>>=(2-i);
-      else chan[i].freq>>=1;
+      if (i<3) {
+        chan[i].freq>>=(2-i);
+      } else {
+        chan[i].freq>>=1;
+      }
      if (chan[i].freq<1) chan[i].freq=1;
      if (chan[i].freq>127) chan[i].freq=0;
      if (isMuted[i]) chan[i].keyOn=false;
--- a/src/engine/platform/vrc6.cpp
+++ b/src/engine/platform/vrc6.cpp
@ -0,0 +1,493 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2022 tildearrow and contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "vrc6.h"
+#include "../engine.h"
+#include <cstddef>
+#include <math.h>
+
+#define rWrite(a,v) if (!skipRegisterWrites) {writes.emplace(a,v); if (dumpWrites) {addWrite(a,v);} }
+#define chWrite(c,a,v) rWrite(0x9000+(c<<12)+(a&3),v)
+
+const char* regCheatSheetVRC6[]={
+  "S0DutyVol", "9000",
+  "S0PeriodL", "9001",
+  "S0PeriodH", "9002",
+  "GlobalCtl", "9003",
+  "S1DutyVol", "A000",
+  "S1PeriodL", "A001",
+  "S1PeriodH", "A002",
+  "SawVolume", "B000",
+  "SawPeriodL", "B001",
+  "SawPeriodH", "B002",
+  "TimerLatch", "F000",
+  "TimerCtl", "F001",
+  "IRQAck", "F002",
+  NULL
+};
+
+const char** DivPlatformVRC6::getRegisterSheet() {
+  return regCheatSheetVRC6;
+}
+
+const char* DivPlatformVRC6::getEffectName(unsigned char effect) {
+  switch (effect) {
+    case 0x12:
+      return "12xx: Set duty cycle (pulse: 0 to 7)";
+      break;
+    case 0x17:
+      return "17xx: Toggle PCM mode (pulse channel)";
+      break;
+  }
+  return NULL;
+}
+
+void DivPlatformVRC6::acquire(short* bufL, short* bufR, size_t start, size_t len) {
+  for (size_t i=start; i<start+len; i++) {
+    // PCM part
+    for (int i=0; i<2; i++) {
+      if (chan[i].pcm && chan[i].dacSample!=-1) {
+        chan[i].dacPeriod+=chan[i].dacRate;
+        if (chan[i].dacPeriod>rate) {
+          DivSample* s=parent->getSample(chan[i].dacSample);
+          if (s->samples<=0) {
+            chan[i].dacSample=-1;
+            chWrite(i,0,0);
+            continue;
+          }
+          unsigned char dacData=(((unsigned char)s->data8[chan[i].dacPos]^0x80)>>4);
+          chan[i].dacOut=MAX(0,MIN(15,(dacData*chan[i].outVol)>>4));
+          if (!isMuted[i]) {
+            chWrite(i,0,0x80|chan[i].dacOut);
+          }
+          chan[i].dacPos++;
+          if (chan[i].dacPos>=s->samples) {
+            if (s->loopStart>=0 && s->loopStart<(int)s->samples) {
+              chan[i].dacPos=s->loopStart;
+            } else {
+              chan[i].dacSample=-1;
+              chWrite(i,0,0);
+            }
+          }
+          chan[i].dacPeriod-=rate;
+        }
+      }
+    }
+
+    // VRC6 part
+    vrc6.tick();
+    int sample=vrc6.out()<<9; // scale to 16 bit
+    if (sample>32767) sample=32767;
+    if (sample<-32768) sample=-32768;
+    bufL[i]=bufR[i]=sample;
+
+    // Command part
+    while (!writes.empty()) {
+      QueuedWrite w=writes.front();
+      switch (w.addr&0xf000) {
+        case 0x9000: // Pulse 1
+          if (w.addr<=0x9003) {
+            if (w.addr==0x9003) {
+              vrc6.control_w(w.val);
+            } else if (w.addr<=0x9002) {
+              vrc6.pulse_w(0,w.addr&3,w.val);
+            }
+            regPool[w.addr-0x9000]=w.val;
+          }
+          break;
+        case 0xa000: // Pulse 2
+          if (w.addr<=0xa002) {
+            vrc6.pulse_w(1,w.addr&3,w.val);
+            regPool[(w.addr-0xa000)+4]=w.val;
+          }
+          break;
+        case 0xb000: // Sawtooth
+          if (w.addr<=0xb002) {
+            vrc6.saw_w(w.addr&3,w.val);
+            regPool[(w.addr-0xb000)+7]=w.val;
+          }
+          break;
+        case 0xf000: // IRQ/Timer
+          if (w.addr<=0xf002) {
+            vrc6.timer_w(w.addr&3,w.val);
+            regPool[(w.addr-0xf000)+10]=w.val;
+          }
+          break;
+      }
+      writes.pop();
+    }
+  }
+}
+
+void DivPlatformVRC6::tick() {
+  for (int i=0; i<3; i++) {
+    // 16 for pulse; 14 for saw
+    int CHIP_DIVIDER=(i==2)?14:16;
+    chan[i].std.next();
+    if (chan[i].std.hadVol) {
+      if (i==2) { // sawtooth
+        chan[i].outVol=((chan[i].vol&63)*MIN(63,chan[i].std.vol))/63;
+        if (chan[i].outVol<0) chan[i].outVol=0;
+        if (chan[i].outVol>63) chan[i].outVol=63;
+        if (!isMuted[i]) {
+          chWrite(i,0,chan[i].outVol);
+        }
+      } else { // pulse
+        chan[i].outVol=((chan[i].vol&15)*MIN(63,chan[i].std.vol))/63;
+        if (chan[i].outVol<0) chan[i].outVol=0;
+        if (chan[i].outVol>15) chan[i].outVol=15;
+        if ((!isMuted[i]) && (!chan[i].pcm)) {
+          chWrite(i,0,(chan[i].outVol&0xf)|((chan[i].duty&7)<<4));
+        }
+      }
+    }
+    if (chan[i].std.hadArp) {
+      if (!chan[i].inPorta) {
+        if (chan[i].std.arpMode) {
+          chan[i].baseFreq=NOTE_PERIODIC(chan[i].std.arp);
+        } else {
+          chan[i].baseFreq=NOTE_PERIODIC(chan[i].note+chan[i].std.arp);
+        }
+      }
+      chan[i].freqChanged=true;
+    } else {
+      if (chan[i].std.arpMode && chan[i].std.finishedArp) {
+        chan[i].baseFreq=NOTE_PERIODIC(chan[i].note);
+        chan[i].freqChanged=true;
+      }
+    }
+    if (chan[i].std.hadDuty) {
+      chan[i].duty=chan[i].std.duty;
+      if ((!isMuted[i]) && (i!=2) && (!chan[i].pcm)) { // pulse
+        chWrite(i,0,(chan[i].outVol&0xf)|((chan[i].duty&7)<<4));
+      }
+    }
+    if (chan[i].freqChanged || chan[i].keyOn || chan[i].keyOff) {
+      if (i==2) { // sawtooth
+        chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,true)-1;
+      } else { // pulse
+        chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,true)-1;
+        if (chan[i].furnaceDac) {
+          double off=1.0;
+          if (chan[i].dacSample>=0 && chan[i].dacSample<parent->song.sampleLen) {
+            DivSample* s=parent->getSample(chan[i].dacSample);
+            if (s->centerRate<1) {
+              off=1.0;
+            } else {
+              off=8363.0/(double)s->centerRate;
+            }
+          }
+          chan[i].dacRate=((double)chipClock)/MAX(1,off*chan[i].freq);
+          if (dumpWrites) addWrite(0xffff0001+(i<<8),chan[i].dacRate);
+        }
+      }
+      if (chan[i].freq>4095) chan[i].freq=4095;
+      if (chan[i].freq<0) chan[i].freq=0;
+      if (chan[i].keyOff) {
+        chWrite(i,2,0);
+      } else {
+        chWrite(i,1,chan[i].freq&0xff);
+        chWrite(i,2,0x80|((chan[i].freq>>8)&0xf));
+      }
+      if (chan[i].keyOn) chan[i].keyOn=false;
+      if (chan[i].keyOff) chan[i].keyOff=false;
+      chan[i].freqChanged=false;
+    }
+  }
+}
+
+int DivPlatformVRC6::dispatch(DivCommand c) {
+  int CHIP_DIVIDER=(c.chan==2)?14:16;
+  switch (c.cmd) {
+    case DIV_CMD_NOTE_ON:
+      if (c.chan!=2) { // pulse wave
+        DivInstrument* ins=parent->getIns(chan[c.chan].ins);
+        if (ins->type==DIV_INS_AMIGA) {
+          chan[c.chan].pcm=true;
+        } else if (chan[c.chan].furnaceDac) {
+          chan[c.chan].pcm=false;
+        }
+        if (chan[c.chan].pcm) {
+          if (skipRegisterWrites) break;
+          if (ins->type==DIV_INS_AMIGA) {
+            chan[c.chan].dacSample=ins->amiga.initSample;
+            if (chan[c.chan].dacSample<0 || chan[c.chan].dacSample>=parent->song.sampleLen) {
+              chan[c.chan].dacSample=-1;
+              if (dumpWrites) addWrite(0xffff0002+(c.chan<<8),0);
+              break;
+            } else {
+              if (dumpWrites) {
+                chWrite(c.chan,2,0x80);
+                chWrite(c.chan,0,isMuted[c.chan]?0:0x80);
+                addWrite(0xffff0000+(c.chan<<8),chan[c.chan].dacSample);
+              }
+            }
+            chan[c.chan].dacPos=0;
+            chan[c.chan].dacPeriod=0;
+            if (c.value!=DIV_NOTE_NULL) {
+              chan[c.chan].baseFreq=NOTE_PERIODIC(c.value);
+              chan[c.chan].freqChanged=true;
+              chan[c.chan].note=c.value;
+            }
+            chan[c.chan].active=true;
+            chan[c.chan].std.init(ins);
+            //chan[c.chan].keyOn=true;
+            chan[c.chan].furnaceDac=true;
+          } else {
+            if (c.value!=DIV_NOTE_NULL) {
+              chan[c.chan].note=c.value;
+            }
+            chan[c.chan].dacSample=12*sampleBank+chan[c.chan].note%12;
+            if (chan[c.chan].dacSample>=parent->song.sampleLen) {
+              chan[c.chan].dacSample=-1;
+              if (dumpWrites) addWrite(0xffff0002+(c.chan<<8),0);
+              break;
+            } else {
+              if (dumpWrites) addWrite(0xffff0000+(c.chan<<8),chan[c.chan].dacSample);
+            }
+            chan[c.chan].dacPos=0;
+            chan[c.chan].dacPeriod=0;
+            chan[c.chan].dacRate=parent->getSample(chan[c.chan].dacSample)->rate;
+            if (dumpWrites) {
+              chWrite(c.chan,2,0x80);
+              chWrite(c.chan,0,isMuted[c.chan]?0:0x80);
+              addWrite(0xffff0001+(c.chan<<8),chan[c.chan].dacRate);
+            }
+            chan[c.chan].furnaceDac=false;
+          }
+          break;
+        }
+      }
+      if (c.value!=DIV_NOTE_NULL) {
+        chan[c.chan].baseFreq=NOTE_PERIODIC(c.value);
+        chan[c.chan].freqChanged=true;
+        chan[c.chan].note=c.value;
+      }
+      chan[c.chan].active=true;
+      chan[c.chan].keyOn=true;
+      chan[c.chan].std.init(parent->getIns(chan[c.chan].ins));
+      if (!isMuted[c.chan]) {
+        if (c.chan==2) { // sawtooth
+          chWrite(c.chan,0,chan[c.chan].vol);
+        } else if (!chan[c.chan].pcm) {
+          chWrite(c.chan,0,(chan[c.chan].vol&0xf)|((chan[c.chan].duty&7)<<4));
+        }
+      }
+      break;
+    case DIV_CMD_NOTE_OFF:
+      chan[c.chan].dacSample=-1;
+      if (dumpWrites) addWrite(0xffff0002+(c.chan<<8),0);
+      chan[c.chan].pcm=false;
+      chan[c.chan].active=false;
+      chan[c.chan].keyOff=true;
+      chan[c.chan].std.init(NULL);
+      break;
+    case DIV_CMD_NOTE_OFF_ENV:
+    case DIV_CMD_ENV_RELEASE:
+      chan[c.chan].std.release();
+      break;
+    case DIV_CMD_INSTRUMENT:
+      if (chan[c.chan].ins!=c.value || c.value2==1) {
+        chan[c.chan].ins=c.value;
+      }
+      break;
+    case DIV_CMD_VOLUME:
+      if (chan[c.chan].vol!=c.value) {
+        chan[c.chan].vol=c.value;
+        if (!chan[c.chan].std.hasVol) {
+          chan[c.chan].outVol=c.value;
+        }
+        if (!isMuted[c.chan]) {
+          if (chan[c.chan].active) {
+            if (c.chan==2) { // sawtooth
+              chWrite(c.chan,0,chan[c.chan].vol);
+            } else if (!chan[c.chan].pcm) {
+              chWrite(c.chan,0,(chan[c.chan].vol&0xf)|((chan[c.chan].duty&7)<<4));
+            }
+          }
+        }
+      }
+      break;
+    case DIV_CMD_GET_VOLUME:
+      return chan[c.chan].vol;
+      break;
+    case DIV_CMD_PITCH:
+      chan[c.chan].pitch=c.value;
+      chan[c.chan].freqChanged=true;
+      break;
+    case DIV_CMD_NOTE_PORTA: {
+      int destFreq=NOTE_PERIODIC(c.value2);
+      bool return2=false;
+      if (destFreq>chan[c.chan].baseFreq) {
+        chan[c.chan].baseFreq+=c.value;
+        if (chan[c.chan].baseFreq>=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      } else {
+        chan[c.chan].baseFreq-=c.value;
+        if (chan[c.chan].baseFreq<=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      }
+      chan[c.chan].freqChanged=true;
+      if (return2) {
+        chan[c.chan].inPorta=false;
+        return 2;
+      }
+      break;
+    }
+    case DIV_CMD_STD_NOISE_MODE:
+      if ((c.chan!=2) && (!chan[c.chan].pcm)) { // pulse
+        chan[c.chan].duty=c.value;
+      }
+      break;
+    case DIV_CMD_SAMPLE_MODE:
+      if (c.chan!=2) { // pulse
+        chan[c.chan].pcm=c.value;
+      }
+      break;
+    case DIV_CMD_SAMPLE_BANK:
+      sampleBank=c.value;
+      if (sampleBank>(parent->song.sample.size()/12)) {
+        sampleBank=parent->song.sample.size()/12;
+      }
+      break;
+    case DIV_CMD_LEGATO:
+      chan[c.chan].baseFreq=NOTE_PERIODIC(c.value+((chan[c.chan].std.willArp && !chan[c.chan].std.arpMode)?(chan[c.chan].std.arp):(0)));
+      chan[c.chan].freqChanged=true;
+      chan[c.chan].note=c.value;
+      break;
+    case DIV_CMD_PRE_PORTA:
+      if (chan[c.chan].active && c.value2) {
+        if (parent->song.resetMacroOnPorta) chan[c.chan].std.init(parent->getIns(chan[c.chan].ins));
+      }
+      chan[c.chan].inPorta=c.value;
+      break;
+    case DIV_CMD_GET_VOLMAX:
+      if (c.chan==2) return 63; // sawtooth has 6 bit volume
+      return 15; // pulse has 4 bit volume
+      break;
+    case DIV_ALWAYS_SET_VOLUME:
+      return 1;
+      break;
+    default:
+      break;
+  }
+  return 1;
+}
+
+void DivPlatformVRC6::muteChannel(int ch, bool mute) {
+  isMuted[ch]=mute;
+  if (isMuted[ch]) {
+    chWrite(ch,0,0);
+  } else if (chan[ch].active) {
+    if (ch==2) { // sawtooth
+      chWrite(ch,0,chan[ch].outVol);
+    } else {
+      chWrite(ch,0,chan[ch].pcm?chan[ch].dacOut:((chan[ch].outVol&0xf)|((chan[ch].duty&7)<<4)));
+    }
+  }
+}
+
+void DivPlatformVRC6::forceIns() {
+  for (int i=0; i<3; i++) {
+    chan[i].insChanged=true;
+    chan[i].freqChanged=true;
+  }
+}
+
+void* DivPlatformVRC6::getChanState(int ch) {
+  return &chan[ch];
+}
+
+unsigned char* DivPlatformVRC6::getRegisterPool() {
+  return regPool;
+}
+
+int DivPlatformVRC6::getRegisterPoolSize() {
+  return 13;
+}
+
+void DivPlatformVRC6::reset() {
+  for (int i=0; i<3; i++) {
+    chan[i]=DivPlatformVRC6::Channel();
+  }
+  if (dumpWrites) {
+    addWrite(0xffffffff,0);
+  }
+
+  sampleBank=0;
+
+  vrc6.reset();
+  // Initialize control register
+  rWrite(0x9003,0);
+  // Clear internal IRQ
+  rWrite(0xf000,0);
+  rWrite(0xf001,0);
+  rWrite(0xf002,0);
+}
+
+bool DivPlatformVRC6::keyOffAffectsArp(int ch) {
+  return true;
+}
+
+void DivPlatformVRC6::setFlags(unsigned int flags) {
+  if (flags==2) { // Dendy
+    rate=COLOR_PAL*2.0/5.0;
+  } else if (flags==1) { // PAL
+    rate=COLOR_PAL*3.0/8.0;
+  } else { // NTSC
+    rate=COLOR_NTSC/2.0;
+  }
+  chipClock=rate;
+}
+
+void DivPlatformVRC6::notifyInsDeletion(void* ins) {
+  for (int i=0; i<3; i++) {
+    chan[i].std.notifyInsDeletion((DivInstrument*)ins);
+  }
+}
+
+void DivPlatformVRC6::poke(unsigned int addr, unsigned short val) {
+  rWrite(addr,val);
+}
+
+void DivPlatformVRC6::poke(std::vector<DivRegWrite>& wlist) {
+  for (DivRegWrite& i: wlist) rWrite(i.addr,i.val);
+}
+
+int DivPlatformVRC6::init(DivEngine* p, int channels, int sugRate, unsigned int flags) {
+  parent=p;
+  dumpWrites=false;
+  skipRegisterWrites=false;
+  for (int i=0; i<3; i++) {
+    isMuted[i]=false;
+  }
+  setFlags(flags);
+  reset();
+  return 3;
+}
+
+void DivPlatformVRC6::quit() {
+}
+
+DivPlatformVRC6::~DivPlatformVRC6() {
+}
--- a/src/engine/platform/vrc6.h
+++ b/src/engine/platform/vrc6.h
@ -0,0 +1,100 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2022 tildearrow and contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef _VRC6_H
+#define _VRC6_H
+
+#include <queue>
+#include "../dispatch.h"
+#include "../macroInt.h"
+#include "sound/vrcvi/vrcvi.hpp"
+
+
+class DivPlatformVRC6: public DivDispatch {
+  struct Channel {
+    int freq, baseFreq, pitch, note;
+    int dacPeriod, dacRate, dacOut;
+    unsigned int dacPos;
+    int dacSample;
+    unsigned char ins, duty;
+    bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, pcm, furnaceDac;
+    signed char vol, outVol;
+    DivMacroInt std;
+    Channel():
+      freq(0),
+      baseFreq(0),
+      pitch(0),
+      note(0),
+      dacPeriod(0),
+      dacRate(0),
+      dacOut(0),
+      dacPos(0),
+      dacSample(-1),
+      ins(-1),
+      duty(0),
+      active(false),
+      insChanged(true),
+      freqChanged(false),
+      keyOn(false),
+      keyOff(false),
+      inPorta(false),
+      pcm(false),
+      furnaceDac(false),
+      vol(15),
+      outVol(15) {}
+  };
+  Channel chan[3];
+  bool isMuted[3];
+  struct QueuedWrite {
+      unsigned short addr;
+      unsigned char val;
+      QueuedWrite(unsigned short a, unsigned char v): addr(a), val(v) {}
+  };
+  std::queue<QueuedWrite> writes;
+  unsigned char sampleBank;
+  vrcvi_intf intf;
+  vrcvi_core vrc6;
+  unsigned char regPool[13];
+
+  friend void putDispatchChan(void*,int,int);
+
+  public:
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
+    int dispatch(DivCommand c);
+    void* getChanState(int chan);
+    unsigned char* getRegisterPool();
+    int getRegisterPoolSize();
+    void reset();
+    void forceIns();
+    void tick();
+    void muteChannel(int ch, bool mute);
+    bool keyOffAffectsArp(int ch);
+    void setFlags(unsigned int flags);
+    void notifyInsDeletion(void* ins);
+    void poke(unsigned int addr, unsigned short val);
+    void poke(std::vector<DivRegWrite>& wlist);
+    const char** getRegisterSheet();
+    const char* getEffectName(unsigned char effect);
+    int init(DivEngine* parent, int channels, int sugRate, unsigned int flags);
+    void quit();
+    DivPlatformVRC6() : vrc6(intf) {};
+    ~DivPlatformVRC6();
+};
+
+#endif
--- a/src/engine/platform/x1_010.h
+++ b/src/engine/platform/x1_010.h
@ -20,7 +20,6 @@
 #ifndef _X1_010_H
 #define _X1_010_H

-#include <queue>
 #include "../dispatch.h"
 #include "../engine.h"
 #include "../macroInt.h"
--- a/src/engine/playback.cpp
+++ b/src/engine/playback.cpp
@ -109,8 +109,14 @@ const char* cmdName[DIV_CMD_MAX]={
  "AY_NOISE_MASK_AND",
  "AY_NOISE_MASK_OR",
  "AY_AUTO_ENVELOPE",
+  "AY_IO_WRITE",
+  "AY_AUTO_PWM",

  "SAA_ENVELOPE",
+
+  "AMIGA_FILTER",
+  "AMIGA_AM",
+  "AMIGA_PM",
  
  "LYNX_LFSR_LOAD",

@ -128,6 +134,18 @@ const char* cmdName[DIV_CMD_MAX]={
  "WS_SWEEP_TIME",
  "WS_SWEEP_AMOUNT",

+  "N163_WAVE_POSITION",
+  "N163_WAVE_LENGTH",
+  "N163_WAVE_MODE",
+  "N163_WAVE_LOAD",
+  "N163_WAVE_LOADPOS",
+  "N163_WAVE_LOADLEN",
+  "N163_CHANNEL_LIMIT",
+  "N163_GLOBAL_WAVE_LOAD",
+  "N163_GLOBAL_WAVE_LOADPOS",
+  "N163_GLOBAL_WAVE_LOADLEN",
+  "N163_GLOBAL_WAVE_LOADMODE",
+
  "ALWAYS_SET_VOLUME"
 };

@ -248,6 +266,51 @@ bool DivEngine::perSystemEffect(int ch, unsigned char effect, unsigned char effe
          return false;
      }
      break;
+    case DIV_SYSTEM_N163:
+      switch (effect) {
+        case 0x10: // select instrument waveform
+          dispatchCmd(DivCommand(DIV_CMD_WAVE,ch,effectVal));
+          break;
+        case 0x11: // select instrument waveform position in RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_WAVE_POSITION,ch,effectVal));
+          break;
+        case 0x12: // select instrument waveform length in RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_WAVE_LENGTH,ch,effectVal));
+          break;
+        case 0x13: // change instrument waveform update mode
+          dispatchCmd(DivCommand(DIV_CMD_N163_WAVE_MODE,ch,effectVal));
+          break;
+        case 0x14: // select waveform for load to RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_WAVE_LOAD,ch,effectVal));
+          break;
+        case 0x15: // select waveform position for load to RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_WAVE_LOADPOS,ch,effectVal));
+          break;
+        case 0x16: // select waveform length for load to RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_WAVE_LOADLEN,ch,effectVal));
+          break;
+        case 0x17: // change waveform load mode
+          dispatchCmd(DivCommand(DIV_CMD_N163_WAVE_LOADMODE,ch,effectVal));
+          break;
+        case 0x18: // change channel limits
+          dispatchCmd(DivCommand(DIV_CMD_N163_CHANNEL_LIMIT,ch,effectVal));
+          break;
+        case 0x20: // (global) select waveform for load to RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_GLOBAL_WAVE_LOAD,ch,effectVal));
+          break;
+        case 0x21: // (global) select waveform position for load to RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_GLOBAL_WAVE_LOADPOS,ch,effectVal));
+          break;
+        case 0x22: // (global) select waveform length for load to RAM
+          dispatchCmd(DivCommand(DIV_CMD_N163_GLOBAL_WAVE_LOADLEN,ch,effectVal));
+          break;
+        case 0x23: // (global) change waveform load mode
+          dispatchCmd(DivCommand(DIV_CMD_N163_GLOBAL_WAVE_LOADMODE,ch,effectVal));
+          break;
+        default:
+          return false;
+      }
+      break;
    case DIV_SYSTEM_QSOUND:
      switch (effect) {
        case 0x10: // echo feedback
@ -324,6 +387,18 @@ bool DivEngine::perSystemEffect(int ch, unsigned char effect, unsigned char effe
          return false;
      }
      break;
+    case DIV_SYSTEM_VRC6:
+      switch (effect) {
+        case 0x12: // duty or noise mode
+          dispatchCmd(DivCommand(DIV_CMD_STD_NOISE_MODE,ch,effectVal));
+          break;
+        case 0x17: // PCM enable
+          dispatchCmd(DivCommand(DIV_CMD_SAMPLE_MODE,ch,(effectVal>0)));
+          break;
+        default:
+          return false;
+      }
+      break;
    default:
      return false;
  }
@ -613,6 +688,12 @@ bool DivEngine::perSystemPostEffect(int ch, unsigned char effect, unsigned char
        case 0x29: // auto-envelope
          dispatchCmd(DivCommand(DIV_CMD_AY_AUTO_ENVELOPE,ch,effectVal));
          break;
+        case 0x2e: // I/O port A
+          dispatchCmd(DivCommand(DIV_CMD_AY_IO_WRITE,ch,0,effectVal));
+          break;
+        case 0x2f: // I/O port B
+          dispatchCmd(DivCommand(DIV_CMD_AY_IO_WRITE,ch,1,effectVal));
+          break;
        default:
          return false;
      }
@ -641,6 +722,21 @@ bool DivEngine::perSystemPostEffect(int ch, unsigned char effect, unsigned char
          return false;
      }
      break;
+    case DIV_SYSTEM_AMIGA:
+      switch (effect) {
+        case 0x10: // toggle filter
+          dispatchCmd(DivCommand(DIV_CMD_AMIGA_FILTER,ch,effectVal));
+          break;
+        case 0x11: // toggle AM
+          dispatchCmd(DivCommand(DIV_CMD_AMIGA_AM,ch,effectVal));
+          break;
+        case 0x12: // toggle PM
+          dispatchCmd(DivCommand(DIV_CMD_AMIGA_PM,ch,effectVal));
+          break;
+        default:
+          return false;
+      }
+      break;
    case DIV_SYSTEM_SEGAPCM:
    case DIV_SYSTEM_SEGAPCM_COMPAT:
      switch (effect) {
@ -742,10 +838,10 @@ void DivEngine::processRow(int i, bool afterDelay) {
      if (disCont[dispatchOfChan[i]].dispatch->keyOffAffectsPorta(dispatchChanOfChan[i])) {
        chan[i].portaNote=-1;
        chan[i].portaSpeed=-1;
-        if (i==2 && sysOfChan[i]==DIV_SYSTEM_SMS) {
+        /*if (i==2 && sysOfChan[i]==DIV_SYSTEM_SMS) {
          chan[i+1].portaNote=-1;
          chan[i+1].portaSpeed=-1;
-        }
+        }*/
      }
      chan[i].scheduledSlideReset=true;
    }
@ -763,10 +859,10 @@ void DivEngine::processRow(int i, bool afterDelay) {
      if (disCont[dispatchOfChan[i]].dispatch->keyOffAffectsPorta(dispatchChanOfChan[i])) {
        chan[i].portaNote=-1;
        chan[i].portaSpeed=-1;
-        if (i==2 && sysOfChan[i]==DIV_SYSTEM_SMS) {
+        /*if (i==2 && sysOfChan[i]==DIV_SYSTEM_SMS) {
          chan[i+1].portaNote=-1;
          chan[i+1].portaSpeed=-1;
-        }
+        }*/
      }
      chan[i].scheduledSlideReset=true;
    }
@ -821,7 +917,7 @@ void DivEngine::processRow(int i, bool afterDelay) {
        }
        break;
      case 0x0d: // next order
-        if (changeOrd<0 && curOrder<(song.ordersLen-1)) {
+        if (changeOrd<0 && (curOrder<(song.ordersLen-1) || !song.ignoreJumpAtEnd)) {
          changeOrd=-2;
          changePos=effectVal;
        }
@ -874,7 +970,7 @@ void DivEngine::processRow(int i, bool afterDelay) {
          chan[i].inPorta=false;
          dispatchCmd(DivCommand(DIV_CMD_PRE_PORTA,i,false,0));
        } else {
-          if (chan[i].note==chan[i].oldNote && !chan[i].inPorta) {
+          if (chan[i].note==chan[i].oldNote && !chan[i].inPorta && song.buggyPortaAfterSlide) {
            chan[i].portaNote=chan[i].note;
            chan[i].portaSpeed=-1;
          } else {
@ -897,8 +993,16 @@ void DivEngine::processRow(int i, bool afterDelay) {
        break;
      case 0x07: // tremolo
        // TODO
+        // this effect is really weird. i thought it would alter the tremolo depth but turns out it's completely different
+        // this is how it works:
+        // - 07xy enables tremolo
+        // - when enabled, a "low" boundary is calculated based on the current volume
+        // - then a volume slide down starts to the low boundary, and then when this is reached a volume slide up begins
+        // - this process repeats until 0700 or 0Axy are found
+        // - note that a volume value does not stop tremolo - instead it glitches this whole thing up
        break;
      case 0x0a: // volume ramp
+        // TODO: non-0x-or-x0 value should be treated as 00
        if (effectVal!=0) {
          if ((effectVal&15)!=0) {
            chan[i].volSpeed=-(effectVal&15)*64;
@ -983,7 +1087,7 @@ void DivEngine::processRow(int i, bool afterDelay) {
          if (chan[i].pitch<-128) chan[i].pitch=-128;
          if (chan[i].pitch>127) chan[i].pitch=127;
        }
-        chan[i].pitch+=globalPitch;
+        //chan[i].pitch+=globalPitch;
        dispatchCmd(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+(((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos]*chan[i].vibratoFine)>>4)/15)));
        break;
      case 0xea: // legato mode
@ -1031,6 +1135,12 @@ void DivEngine::processRow(int i, bool afterDelay) {
        chan[i].inPorta=false;
        if (!song.arpNonPorta) dispatchCmd(DivCommand(DIV_CMD_PRE_PORTA,i,false,0));
        break;
+      case 0xf3: // fine volume ramp up
+        chan[i].volSpeed=effectVal;
+        break;
+      case 0xf4: // fine volume ramp down
+        chan[i].volSpeed=-effectVal;
+        break;
      case 0xf8: // single volume ramp up
        chan[i].volume=MIN(chan[i].volume+effectVal*256,chan[i].volMax);
        dispatchCmd(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
@ -1229,6 +1339,7 @@ void DivEngine::nextRow() {
  }

  if (haltOn==DIV_HALT_ROW) halted=true;
+  firstTick=true;
 }

 bool DivEngine::nextTick(bool noAccum) {
@ -1281,23 +1392,25 @@ bool DivEngine::nextTick(bool noAccum) {
          keyHit[i]=true;
        }
      }
-      if (chan[i].volSpeed!=0) {
-        chan[i].volume=(chan[i].volume&0xff)|(dispatchCmd(DivCommand(DIV_CMD_GET_VOLUME,i))<<8);
-        chan[i].volume+=chan[i].volSpeed;
-        if (chan[i].volume>chan[i].volMax) {
-          chan[i].volume=chan[i].volMax;
-          chan[i].volSpeed=0;
-          dispatchCmd(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
-        } else if (chan[i].volume<0) {
-          chan[i].volSpeed=0;
-          if (song.legacyVolumeSlides) {
-            chan[i].volume=chan[i].volMax+1;
+      if (!song.noSlidesOnFirstTick || !firstTick) {
+        if (chan[i].volSpeed!=0) {
+          chan[i].volume=(chan[i].volume&0xff)|(dispatchCmd(DivCommand(DIV_CMD_GET_VOLUME,i))<<8);
+          chan[i].volume+=chan[i].volSpeed;
+          if (chan[i].volume>chan[i].volMax) {
+            chan[i].volume=chan[i].volMax;
+            chan[i].volSpeed=0;
+            dispatchCmd(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
+          } else if (chan[i].volume<0) {
+            chan[i].volSpeed=0;
+            if (song.legacyVolumeSlides) {
+              chan[i].volume=chan[i].volMax+1;
+            } else {
+              chan[i].volume=0;
+            }
+            dispatchCmd(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
          } else {
-            chan[i].volume=0;
+            dispatchCmd(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
          }
-          dispatchCmd(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
-        } else {
-          dispatchCmd(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
        }
      }
      if (chan[i].vibratoDepth>0) {
@ -1315,13 +1428,15 @@ bool DivEngine::nextTick(bool noAccum) {
            break;
        }
      }
-      if ((chan[i].keyOn || chan[i].keyOff) && chan[i].portaSpeed>0) {
-        if (dispatchCmd(DivCommand(DIV_CMD_NOTE_PORTA,i,chan[i].portaSpeed,chan[i].portaNote))==2 && chan[i].portaStop && song.targetResetsSlides) {
-          chan[i].portaSpeed=0;
-          chan[i].oldNote=chan[i].note;
-          chan[i].note=chan[i].portaNote;
-          chan[i].inPorta=false;
-          dispatchCmd(DivCommand(DIV_CMD_LEGATO,i,chan[i].note));
+      if (!song.noSlidesOnFirstTick || !firstTick) {
+        if ((chan[i].keyOn || chan[i].keyOff) && chan[i].portaSpeed>0) {
+          if (dispatchCmd(DivCommand(DIV_CMD_NOTE_PORTA,i,chan[i].portaSpeed,chan[i].portaNote))==2 && chan[i].portaStop && song.targetResetsSlides) {
+            chan[i].portaSpeed=0;
+            chan[i].oldNote=chan[i].note;
+            chan[i].note=chan[i].portaNote;
+            chan[i].inPorta=false;
+            dispatchCmd(DivCommand(DIV_CMD_LEGATO,i,chan[i].note));
+          }
        }
      }
      if (chan[i].cut>0) {
@ -1339,10 +1454,10 @@ bool DivEngine::nextTick(bool noAccum) {
            if (disCont[dispatchOfChan[i]].dispatch->keyOffAffectsPorta(dispatchChanOfChan[i])) {
              chan[i].portaNote=-1;
              chan[i].portaSpeed=-1;
-              if (i==2 && sysOfChan[i]==DIV_SYSTEM_SMS) {
+              /*if (i==2 && sysOfChan[i]==DIV_SYSTEM_SMS) {
                chan[i+1].portaNote=-1;
                chan[i+1].portaSpeed=-1;
-              }
+              }*/
            }
            dispatchCmd(DivCommand(DIV_CMD_PRE_PORTA,i,false,0));
            chan[i].scheduledSlideReset=true;
@ -1354,6 +1469,9 @@ bool DivEngine::nextTick(bool noAccum) {
        dispatchCmd(DivCommand(DIV_CMD_LEGATO,i,chan[i].note));
        chan[i].resetArp=false;
      }
+      if (song.rowResetsArpPos && firstTick) {
+        chan[i].arpStage=-1;
+      }
      if (chan[i].arp!=0 && !chan[i].arpYield && chan[i].portaSpeed<1) {
        if (--chan[i].arpTicks<1) {
          chan[i].arpTicks=song.arpLen;
@ -1377,6 +1495,8 @@ bool DivEngine::nextTick(bool noAccum) {
    }
  }

+  firstTick=false;
+
  // system tick
  for (int i=0; i<song.systemLen; i++) disCont[i].dispatch->tick();

--- a/src/engine/song.h
+++ b/src/engine/song.h
@ -302,6 +302,11 @@ struct DivSong {
  bool newInsTriggersInPorta;
  bool arp0Reset;
  bool brokenSpeedSel;
+  bool noSlidesOnFirstTick;
+  bool rowResetsArpPos;
+  bool ignoreJumpAtEnd;
+  bool buggyPortaAfterSlide;
+  bool gbInsAffectsEnvelope;

  DivOrders orders;
  std::vector<DivInstrument*> ins;
@ -375,7 +380,12 @@ struct DivSong {
    oneTickCut(false),
    newInsTriggersInPorta(true),
    arp0Reset(true),
-    brokenSpeedSel(false) {
+    brokenSpeedSel(false),
+    noSlidesOnFirstTick(false),
+    rowResetsArpPos(false),
+    ignoreJumpAtEnd(false),
+    buggyPortaAfterSlide(false),
+    gbInsAffectsEnvelope(true) {
    for (int i=0; i<32; i++) {
      system[i]=DIV_SYSTEM_NULL;
      systemVol[i]=64;
--- a/src/gui/about.cpp
+++ b/src/gui/about.cpp
@ -47,6 +47,7 @@ const char* aboutLine[]={
  "-- graphics/UI design --",
  "tildearrow",
  "BlastBrothers",
+  "Raijin",
  "",
  "-- documentation --",
  "tildearrow",
--- a/src/gui/compatFlags.cpp
+++ b/src/gui/compatFlags.cpp
@ -85,6 +85,26 @@ void FurnaceGUI::drawCompatFlags() {
    if (ImGui::IsItemHovered()) {
      ImGui::SetTooltip("determines next speed based on whether the row is odd/even instead of alternating between speeds.");
    }
+    ImGui::Checkbox("Don't slide on the first tick of a row",&e->song.noSlidesOnFirstTick);
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("simulates ProTracker's behavior of not applying volume/pitch slides on the first tick of a row.");
+    }
+    ImGui::Checkbox("Reset arpeggio position on row change",&e->song.rowResetsArpPos);
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("simulates ProTracker's behavior of arpeggio being bound to the current tick of a row.");
+    }
+    ImGui::Checkbox("Ignore 0Dxx on the last order",&e->song.ignoreJumpAtEnd);
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("if this is on, a jump to next row effect will not take place when it is on the last order of a song.");
+    }
+    ImGui::Checkbox("Buggy portamento after pitch slide",&e->song.buggyPortaAfterSlide);
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("simulates a bug in where portamento does not work after sliding.");
+    }
+    ImGui::Checkbox("Apply Game Boy envelope on note-less instrument change",&e->song.gbInsAffectsEnvelope);
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("if this is on, an instrument change will also affect the envelope.");
+    }

    ImGui::Text("Loop modality:");
    if (ImGui::RadioButton("Reset channels",e->song.loopModality==0)) {
--- a/src/gui/debug.cpp
+++ b/src/gui/debug.cpp
@ -37,6 +37,8 @@
 #include "../engine/platform/saa.h"
 #include "../engine/platform/amiga.h"
 #include "../engine/platform/x1_010.h"
+#include "../engine/platform/n163.h"
+#include "../engine/platform/vrc6.h"
 #include "../engine/platform/dummy.h"

 #define GENESIS_DEBUG \
@ -274,6 +276,63 @@ void putDispatchChan(void* data, int chanNum, int type) {
      ImGui::TextColored(ch->env.flag.envVinvL?colorOn:colorOff,">> EnvVinvL");
      break;
    }
+    case DIV_SYSTEM_N163: {
+      DivPlatformN163::Channel* ch=(DivPlatformN163::Channel*)data;
+      ImGui::Text("> N163");
+      ImGui::Text("* freq: %.4x",ch->freq);
+      ImGui::Text(" - base: %d",ch->baseFreq);
+      ImGui::Text(" - pitch: %d",ch->pitch);
+      ImGui::Text("- note: %d",ch->note);
+      ImGui::Text("- wave: %d",ch->wave);
+      ImGui::Text("- wavepos: %d",ch->wavePos);
+      ImGui::Text("- wavelen: %d",ch->waveLen);
+      ImGui::Text("- wavemode: %d",ch->waveMode);
+      ImGui::Text("- loadwave: %d",ch->loadWave);
+      ImGui::Text("- loadpos: %d",ch->loadPos);
+      ImGui::Text("- loadlen: %d",ch->loadLen);
+      ImGui::Text("- loadmode: %d",ch->loadMode);
+      ImGui::Text("- ins: %d",ch->ins);
+      ImGui::Text("- vol: %.2x",ch->vol);
+      ImGui::Text("- outVol: %.2x",ch->outVol);
+      ImGui::Text("- resVol: %.2x",ch->resVol);
+      ImGui::TextColored(ch->active?colorOn:colorOff,">> Active");
+      ImGui::TextColored(ch->insChanged?colorOn:colorOff,">> InsChanged");
+      ImGui::TextColored(ch->freqChanged?colorOn:colorOff,">> FreqChanged");
+      ImGui::TextColored(ch->volumeChanged?colorOn:colorOff,">> VolumeChanged");
+      ImGui::TextColored(ch->waveChanged?colorOn:colorOff,">> WaveChanged");
+      ImGui::TextColored(ch->waveUpdated?colorOn:colorOff,">> WaveUpdated");
+      ImGui::TextColored(ch->keyOn?colorOn:colorOff,">> KeyOn");
+      ImGui::TextColored(ch->keyOff?colorOn:colorOff,">> KeyOff");
+      ImGui::TextColored(ch->inPorta?colorOn:colorOff,">> InPorta");
+      break;
+    }
+    case DIV_SYSTEM_VRC6: {
+      DivPlatformVRC6::Channel* ch=(DivPlatformVRC6::Channel*)data;
+      ImGui::Text("> VRC6");
+      ImGui::Text("* freq: %d",ch->freq);
+      ImGui::Text(" - base: %d",ch->baseFreq);
+      ImGui::Text(" - pitch: %d",ch->pitch);
+      ImGui::Text("- note: %d",ch->note);
+      ImGui::Text("* DAC:");
+      ImGui::Text(" - period: %d",ch->dacPeriod);
+      ImGui::Text(" - rate: %d",ch->dacRate);
+      ImGui::Text(" - out: %d",ch->dacOut);
+      ImGui::Text(" - pos: %d",ch->dacPos);
+      ImGui::Text(" - sample: %d",ch->dacSample);
+      ImGui::Text("- ins: %d",ch->ins);
+      ImGui::Text("- duty: %d",ch->duty);
+      ImGui::Text("- vol: %.2x",ch->vol);
+      ImGui::Text("- outVol: %.2x",ch->outVol);
+      ImGui::TextColored(ch->active?colorOn:colorOff,">> Active");
+      ImGui::TextColored(ch->insChanged?colorOn:colorOff,">> InsChanged");
+      ImGui::TextColored(ch->freqChanged?colorOn:colorOff,">> FreqChanged");
+      ImGui::TextColored(ch->keyOn?colorOn:colorOff,">> KeyOn");
+      ImGui::TextColored(ch->keyOff?colorOn:colorOff,">> KeyOff");
+      ImGui::TextColored(ch->inPorta?colorOn:colorOff,">> InPorta");
+      ImGui::TextColored(ch->pcm?colorOn:colorOff,">> DAC");
+      ImGui::TextColored(ch->furnaceDac?colorOn:colorOff,">> FurnaceDAC");
+      break;
+    }
    default:
      ImGui::Text("Unknown system! Help!");
      break;
--- a/src/gui/gui.h
+++ b/src/gui/gui.h
@ -622,6 +622,8 @@ class FurnaceGUI {
    int roundedButtons;
    int roundedMenus;
    int loadJapanese;
+    int fmLayout;
+    int susPosition;
    unsigned int maxUndoSteps;
    String mainFontPath;
    String patFontPath;
@ -672,6 +674,8 @@ class FurnaceGUI {
      roundedButtons(1),
      roundedMenus(0),
      loadJapanese(0),
+      fmLayout(0),
+      susPosition(0),
      maxUndoSteps(100),
      mainFontPath(""),
      patFontPath(""),
@ -819,6 +823,8 @@ class FurnaceGUI {
  float keyHit[DIV_MAX_CHANS];
  int lastIns[DIV_MAX_CHANS];

+  void drawSSGEnv(unsigned char type, const ImVec2& size);
+  void drawWaveform(unsigned char type, bool opz, const ImVec2& size);
  void drawAlgorithm(unsigned char alg, FurnaceGUIFMAlgs algType, const ImVec2& size);
  void drawFMEnv(unsigned char tl, unsigned char ar, unsigned char dr, unsigned char d2r, unsigned char rr, unsigned char sl, float maxTl, float maxArDr, const ImVec2& size);
  void drawSysConf(int i);
--- a/src/gui/guiConst.cpp
+++ b/src/gui/guiConst.cpp
@ -163,7 +163,9 @@ const int availableSystems[]={
  DIV_SYSTEM_SWAN,
  DIV_SYSTEM_VERA,
  DIV_SYSTEM_BUBSYS_WSG,
+  DIV_SYSTEM_N163,
  DIV_SYSTEM_PET,
  DIV_SYSTEM_VIC20,
+  DIV_SYSTEM_VRC6,
  0 // don't remove this last one!
 };
--- a/src/gui/insEdit.cpp
+++ b/src/gui/insEdit.cpp
--- a/src/gui/intConst.cpp
+++ b/src/gui/intConst.cpp
@ -29,6 +29,7 @@ const int _THIRTY_ONE=31;
 const int _SIXTY_FOUR=64;
 const int _ONE_HUNDRED=100;
 const int _ONE_HUNDRED_TWENTY_SEVEN=127;
+const int _TWO_HUNDRED_FIFTY_FIVE=255;
 const int _TWO_THOUSAND_FORTY_SEVEN=2047;
 const int _FOUR_THOUSAND_NINETY_FIVE=4095;
 const int _MINUS_ONE_HUNDRED_TWENTY_SEVEN=-127;
--- a/src/gui/intConst.h
+++ b/src/gui/intConst.h
@ -31,6 +31,7 @@ extern const int _THIRTY_ONE;
 extern const int _SIXTY_FOUR;
 extern const int _ONE_HUNDRED;
 extern const int _ONE_HUNDRED_TWENTY_SEVEN;
+extern const int _TWO_HUNDRED_FIFTY_FIVE;
 extern const int _TWO_THOUSAND_FORTY_SEVEN;
 extern const int _FOUR_THOUSAND_NINETY_FIVE;
 extern const int _MINUS_ONE_HUNDRED_TWENTY_SEVEN;
--- a/src/gui/pattern.cpp
+++ b/src/gui/pattern.cpp
@ -65,8 +65,8 @@ const FurnaceGUIColors extFxColors[32]={
  GUI_COLOR_PATTERN_EFFECT_SPEED, // F0
  GUI_COLOR_PATTERN_EFFECT_PITCH, // F1
  GUI_COLOR_PATTERN_EFFECT_PITCH, // F2
-  GUI_COLOR_PATTERN_EFFECT_INVALID, // F3
-  GUI_COLOR_PATTERN_EFFECT_INVALID, // F4
+  GUI_COLOR_PATTERN_EFFECT_VOLUME, // F3
+  GUI_COLOR_PATTERN_EFFECT_VOLUME, // F4
  GUI_COLOR_PATTERN_EFFECT_INVALID, // F5
  GUI_COLOR_PATTERN_EFFECT_INVALID, // F6
  GUI_COLOR_PATTERN_EFFECT_INVALID, // F7
--- a/src/gui/presets.cpp
+++ b/src/gui/presets.cpp
@ -227,6 +227,13 @@ void FurnaceGUI::initSystemPresets() {
      0
    }
  ));
+  cat.systems.push_back(FurnaceGUISysDef(
+    "NES with Konami VRC6", {
+      DIV_SYSTEM_NES, 64, 0, 0,
+      DIV_SYSTEM_VRC6, 64, 0, 0,
+      0
+    }
+  ));
  cat.systems.push_back(FurnaceGUISysDef(
    "NES with Konami VRC7", {
      DIV_SYSTEM_NES, 64, 0, 0,
@ -241,6 +248,13 @@ void FurnaceGUI::initSystemPresets() {
      0
    }
  ));
+  cat.systems.push_back(FurnaceGUISysDef(
+    "NES with Namco 163", {
+      DIV_SYSTEM_NES, 64, 0, 0,
+      DIV_SYSTEM_N163, 64, 0, 112,
+      0
+    }
+  ));
  cat.systems.push_back(FurnaceGUISysDef(
    "NES with Family Noraebang", {
      DIV_SYSTEM_NES, 64, 0, 0,
--- a/src/gui/settings.cpp
+++ b/src/gui/settings.cpp
@ -419,6 +419,28 @@ void FurnaceGUI::drawSettings() {
          settings.controlLayout=3;
        }

+        ImGui::Text("FM parameter editor layout:");
+        if (ImGui::RadioButton("Modern##fml0",settings.fmLayout==0)) {
+          settings.fmLayout=0;
+        }
+        if (ImGui::RadioButton("Compact (2x2, classic)##fml1",settings.fmLayout==1)) {
+          settings.fmLayout=1;
+        }
+        if (ImGui::RadioButton("Compact (1x4)##fml2",settings.fmLayout==2)) {
+          settings.fmLayout=2;
+        }
+        if (ImGui::RadioButton("Compact (4x1)##fml3",settings.fmLayout==3)) {
+          settings.fmLayout=3;
+        }
+
+        ImGui::Text("Position of Sustain in FM editor:");
+        if (ImGui::RadioButton("Between Decay and Sustain Rate##susp0",settings.susPosition==0)) {
+          settings.susPosition=0;
+        }
+        if (ImGui::RadioButton("After Release Rate##susp1",settings.susPosition==1)) {
+          settings.susPosition=1;
+        }
+
        bool macroViewB=settings.macroView;
        if (ImGui::Checkbox("Classic macro view (standard macros only; deprecated!)",&macroViewB)) {
          settings.macroView=macroViewB;
@ -990,6 +1012,8 @@ void FurnaceGUI::syncSettings() {
  settings.roundedButtons=e->getConfInt("roundedButtons",1);
  settings.roundedMenus=e->getConfInt("roundedMenus",0);
  settings.loadJapanese=e->getConfInt("loadJapanese",0);
+  settings.fmLayout=e->getConfInt("fmLayout",0);
+  settings.susPosition=e->getConfInt("susPosition",0);

  clampSetting(settings.mainFontSize,2,96);
  clampSetting(settings.patFontSize,2,96);
@ -1034,6 +1058,8 @@ void FurnaceGUI::syncSettings() {
  clampSetting(settings.roundedButtons,0,1);
  clampSetting(settings.roundedMenus,0,1);
  clampSetting(settings.loadJapanese,0,1);
+  clampSetting(settings.fmLayout,0,3);
+  clampSetting(settings.susPosition,0,1);

  // keybinds
  LOAD_KEYBIND(GUI_ACTION_OPEN,FURKMOD_CMD|SDLK_o);
@ -1268,6 +1294,8 @@ void FurnaceGUI::commitSettings() {
  e->setConf("roundedButtons",settings.roundedButtons);
  e->setConf("roundedMenus",settings.roundedMenus);
  e->setConf("loadJapanese",settings.loadJapanese);
+  e->setConf("fmLayout",settings.fmLayout);
+  e->setConf("susPosition",settings.susPosition);

  PUT_UI_COLOR(GUI_COLOR_BACKGROUND);
  PUT_UI_COLOR(GUI_COLOR_FRAME_BACKGROUND);
--- a/src/gui/sysConf.cpp
+++ b/src/gui/sysConf.cpp
@ -147,6 +147,7 @@ void FurnaceGUI::drawSysConf(int i) {
      }
      break;
    case DIV_SYSTEM_NES:
+    case DIV_SYSTEM_VRC6:
      if (ImGui::RadioButton("NTSC (1.79MHz)",flags==0)) {
        e->setSysFlags(i,0,restart);
        updateWindowTitle();
@ -347,6 +348,30 @@ void FurnaceGUI::drawSysConf(int i) {
      }
      break;
    }
+    case DIV_SYSTEM_N163: {
+      ImGui::Text("Clock rate:");
+      if (ImGui::RadioButton("NTSC (1.79MHz)",(flags&15)==0)) {
+        e->setSysFlags(i,(flags&(~15))|0,restart);
+        updateWindowTitle();
+      }
+      if (ImGui::RadioButton("PAL (1.67MHz)",(flags&15)==1)) {
+        e->setSysFlags(i,(flags&(~15))|1,restart);
+        updateWindowTitle();
+      }
+      if (ImGui::RadioButton("Dendy (1.77MHz)",(flags&15)==2)) {
+        e->setSysFlags(i,(flags&(~15))|2,restart);
+        updateWindowTitle();
+      }
+      ImGui::Text("Initial channel limit:");
+      int initialChannelLimit=((flags>>4)&7)+1;
+      if (ImGui::SliderInt("##InitialChannelLimit",&initialChannelLimit,1,8)) {
+        if (initialChannelLimit<1) initialChannelLimit=1;
+        if (initialChannelLimit>8) initialChannelLimit=8;
+        e->setSysFlags(i,(flags & ~(7 << 4)) | (((initialChannelLimit-1) & 7) << 4),restart);
+        updateWindowTitle();
+      } rightClickable
+      break;
+    }
    case DIV_SYSTEM_GB:
    case DIV_SYSTEM_SWAN:
    case DIV_SYSTEM_VERA:
--- a/src/gui/waveEdit.cpp
+++ b/src/gui/waveEdit.cpp
@ -37,7 +37,7 @@ void FurnaceGUI::drawWaveEdit() {
      DivWavetable* wave=e->song.wave[curWave];
      ImGui::Text("Width");
      if (ImGui::IsItemHovered()) {
-        ImGui::SetTooltip("use a width of:\n- any on Amiga/X1-010\n- 32 on Game Boy, PC Engine and WonderSwan\nany other widths will be scaled during playback.");
+        ImGui::SetTooltip("use a width of:\n- any on Amiga/N163\n- 32 on Game Boy, PC Engine and WonderSwan\n- 128 on X1-010\nany other widths will be scaled during playback.");
      }
      ImGui::SameLine();
      ImGui::SetNextItemWidth(128.0f*dpiScale);
@ -51,7 +51,7 @@ void FurnaceGUI::drawWaveEdit() {
      ImGui::SameLine();
      ImGui::Text("Height");
      if (ImGui::IsItemHovered()) {
-        ImGui::SetTooltip("use a height of:\n- 15 for Game Boy and WonderSwan\n- 31 for PC Engine\nany other heights will be scaled during playback.");
+        ImGui::SetTooltip("use a height of:\n- 15 for Game Boy, WonderSwan, X1-010 Envelope shape and N163\n- 31 for PC Engine\n- 255 for X1-010\nany other heights will be scaled during playback.");
      }
      ImGui::SameLine();
      ImGui::SetNextItemWidth(128.0f*dpiScale);