Before we get to the chips,
here are a few things I'd be happy if you could help me with:


Maybe you have the card or have downloaded a card image of Roland FANXRUP1 or FANXUP1 that was once floating around the web? If you have the card but don't know how to create an exact backup of it, I'll help you with it - it's easy. I've also kludged up an aternative upgrader v1→v2 package a very long time ago, however it, while fully works, after starting up still gets caught in some little trick that needs to be found out and fixed. To fix it and make proper upgrader for everyone, I need someone that is handy with SH3/7706 (HD6417706) disasembles and reverse engineering. I've extracted and decompressed everything necessary and see the guilty spot that needs to be patched, however I (at least currently) don't do SH3.

Also, I'm looking for Yamaha PSR-2700 demo diskette contents that likely have been archived somewhere.

Maybe someone has a Yamaha PCS-30 (or PC-50, PCS-500, PC-1000) service manual and/or schematics for it? Since I've made way over two hundred Playcards available to you (and also tested absolutely all my binaries as well!), working out the hardware and firmware of this thing is important, since this one, instead of a custom playcard sequence playback chip, uses a stock Z80!

I'm looking for an Alesis WEDGE rom dump, Alesis XT:C rom dump and also Alesis XT-Reverb rom dump, Here's a MidiVerb dump for you in exchange. In fact, you can find tons of my dumped roms on this great webpage.

How come noone seems to have dumped Roland DDR-30 waverom? I'm tempted to buy Bought one just to make dumps (for all of you, btw!), but I already have a hundred more other synths to desolder and dump in queue, so probably won't go for it. If you have one - dump all the roms and let me know! It just should will be put on this great website. (already bought it and dumped program and all wave roms)

Any of the ART MultiVerb, ProVerb or similar reverbs/effect rom dumps are also of interest for me, for example I'm looking for ART Proverb 200 - here's an ART Multiverb LT dump for you in exchange.

Judging by the immense popularity of PSS-51 in eastern europe, asia and amongst russians, it is quite hard to believe that no one have dumped its roms. Maybe you have dumps of Yamaha PSS-51 program, abc and/or waveroms? Or maybe you know one for local pickup somewhere within Baltic states? Well, just bought and dumped it, and extracted samples, demos and styles. Also I've previously made dumps of rather similar PSS-795 and PSS-595.

It seems there that earliest version (A00) of the Yamaha FB01 firmware rom is somewhat rare, and I esimate, based on the units that I have, that at most 10%-20% of the units in the wild do have it. All usual ones have the most-likely-final C00, that I have desoldered, dumped and shared in the long-ago ancient times. However, for the sake of history and disassembly fun, having A00 dumped is a must as well, though I don't realy have too much of spare time to desolder and dump it, especially since maybe someone has already dumped this version (given the popularity and abundance of these modules). So if you have it, let me know. At some point I might desolder it and dump it, if it turns out to be realy rare, but I'd better spend that time desoldering and dumping something else.
Also, for the curious, initial hardware version (with A00 rom) only differs with (besides missing ground wire from the pcb inside) that it does not have a metal sub-chasis under the pcb, so you can tell that from the outside by looking from the bottom: early ones have two holes, but no screws in them, and instead has white plastic pegs in other holes right besides front panel. Serial numbers for the A00 version seem to be below 02000, while 07000 and up definitely has version C00. No idea about if there was a B00 version in betwen 02000 and 07000.
(I will likely make a separate article on FB-01 at some point)

In regards to multieffect pedals - maybe you have a rom dump of Roland/BOSS GT-10B? There in this great webpage you can find my GT-3,5,6,8 dumps.

And maybe someone has already desoldered and dumped PSR-6000 waveroms? Those are three pieces of DIP42 chips, each 2Mbyte (besides two more chips with styles and then two DIP40 with program and demo songs). I am somewhat tempted to grab one from the local trash market to do this, yet not sure if I realy have to. And I don't have a clue when I could actually get to desoldering it, even if I' ll grab one now. Still GEW9 stuff seems rather interesting and not that common to come by in the keyboards.

Thanks, I now got the floppy files from Casio WK-1800 Accessory Disk (demo disk that came with it). I will eventually make a page about this idea and what has been done (if anything), but for now this text blob is just to keep the following from the old post for those who are interested: You might like the main reason I'm lookig for it - it is clearly a fun attack vector to non-destructively dump its maskrom (in Hitachi H8) since it actually allows to execute arbitrary code! While dumping can be done even by blinking a led chdk-style, in this case there's already initialized and working uart for that. Furthermore, if all is well, waveroms (8Mbyte total) can also be dumped this way, since H8 can quickly access them, and procedure to do this for studying will be in the maskrom. On the other hand, I'll very likely at some point just desolder and dump waveroms anyways - but it could be more epic to dump it via diskette and midi.

In regards to spare parts and hardware things that I'm missing, maybe you have this:
* Display from early 2000s - Kyocera KCG057QV1DB-G00 found in old Fantom-X keyboards (Roland part code: 03560889 "DISPLAY UNIT LCD KCG057QV1DB-G00").

If you do, please email me!



Yamaha Chips

This is an attempt to create the most extensive Yamaha synth chip list ever. Includes hard/impossibe to find pinouts, too.
Information, that I add here, is mostly checked/confirmed/found out by myself, unless sometimes otherwise noted.
 

Yamaha OPJ custom hardware sound module
  • YA series
  • YM series
  • YMF series
  • YMW
  • YMU
  • YSD
  • YSP
  • YSS series
  • iG custom ASICs
  • TC (some custom ASICs for yamaha manufactured by Toshiba)
  • HG
  • JG

Currently under construction. I am going to fill up the cells, add pinouts, missing entries and lists gradually, whenever I will find some spare time for doing it.

Распайка, распиновка, データシート

By the way, I do not sell these chips. This table is for a rather comprehensive reference of what can be found in most of yamaha synthesizers - so it's easier to find some documentation on similar innards for an instrument, that has otherwise no documentation avalable.

This reference table also allows to quite precisely assess the character and quality of the sound for a particular keyboard, by knowing the sound of other similar ones. Common DSP/FM source produces rather similar sound on any sythesizer based around the same chip, or at least have similar certain aspects, particular character or oddities of the sound.

Intuitively, initial meanings of certain tone generator dsp designations might have been a litle different than the ones given in the documentation:
SWL - Standard Wave Low-cost or Lite (and there's even lowcost-ier thing than these ones, called SWLL)
SWX - Standard Wave XG-ish (medium-grade stuff with at least 32 voice poly, filters and effects)
SWP - Standard Wave Professional (almost all can sound truly great, though there is also a low-cost cut down L-versions that does not)


YM series

IC name
Yamaha's alias
Yamahas official short description
My notes
Used in (synths)
YM001


Their first chip is just a clone of LM3211
YC-45D
YM248 00
SSK

Keyscanner, converting into CV and TRIG
CS-30
YM254 (pinout)


Reference frequency divider, typical thing in electronic organs. Generates reference (high) frequencies for every semitone from one high frequency oscillator. D-30, YC-45D
YM311
KC
"Key Coder"


YM312
CP
"Channel Processor"


YM316
ACC
"Accumulator"


YM318
MPX
"Multiplexer"


YM320
IG
"Initial touch Generator"


YM321
EG
"Envelope Generator"


YM322
EC
"Envelope Controller"


YM327
ADD
"Adder"


YM334
AG
"Aftertouch Generator"


YM344
PG
"Phase Generator"


YM347
VRG
"Voice Register"


YM351 00
(pinout)

"Low Noise 512 Stage BBD"
Classic BBD delay line for chorus.
MR-500, FS-50, FS-70, FS-300, FS-500
YM351 00B



FS-50, FS-70
YM601 00
KAS
"Key Assigner"

Electone C-55N, C-200
YM603 00
ROM II
"Auto Rhythm, Auto Bass Chord"
Weird special rom with drum trigger outputs.
C-200
YM604
"Digital Tone Generator I"
As reported by Claus
Electone A-55N
YM605 00
DTGII
"Tone Generator II"

Electone C-55N, C-200
YM606 00 DTG III
"Tone Generator III"

C-200
YM607 00
DTG IV "Tone Generator IV"
Electone C-55N, C-200
YM608 00
(pinout)
SEC
"Symphonic Chorus Clock Generator"
"String Ensemble Clock Generator"

C-55N, FS-50, FS-70, FS-300, FS-500
YM614 00
DTG III "Tone Generator III" Same name as the YM606 00.
Electone C-55N
YM621 00
KAC
"Key Assigner C"

Electone D-700, D-800
YM624 00
SCA


Electone D-800
YM626 DVG
"Delay Vibrato Generator"

Electone A-55N, C-55N, D-700, D-800
YM627
PSC


Electone D-700, D-800
YM630
RGC I


Electone D-700, D-800
YM631
RGC II


Electone D-700, D-800
YM632
RGC III


Electone D-700, D-800
YM633 00
SEC-II
"Symphonic Ensemble Controller"
"Symphonic Ensemble Clock Generator 2"
BBD/CCD delay line chip control generator
MR-500
YM634 ROM V "Rhythm Generator"
Electone A-55N
YM635 00
ROM VI
"Rhythm Generator"
Some logic with rom that directly triggers drums accordingly to a selected pattern.
Electone C-55N
YM636
CPA
"Key Assigner Channel Prossesor" (sic)

CP-35
YM705
GSC


Electone D-700, D-800
YM706
GAP
"Arpeggio and Pedal Generator"

Electone D-700, D-800
YM707
GVE


Electone D-800
YM708
VCS


Electone D-700, D-800
YM709
VCC


Electone D-700, D-800
YM710
VCP
"Pedal Voice Control"

Electone D-700, D-800
YM711
VCM


Electone D-800
YM722
CPB
"Wave Source"

CP-35
YM801
WG I
"Wave Generator I"
One of those beautifuly scary vintage ceramic chips with 82 pins. Electone D-700
YM802
WG II
"Wave Generator II" One of those beautifuly scary vintage ceramic chips with 82 pins.
Electone D-800
YM806
(pinout)
OPA
"Operator" also "OPE-OPRC"
Functions as OPE or OPRC (ensemble or rhythm) based on control data.
FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM1001 KAR
"Key Assigner & Rhythm"
PS-20, ?PS-30
YM10010
KAR
"Key Assigner & Rhythm"
DIP40
CN-70
YM1002
PSC II
"Parallel - Serial Converter" DIP16 (likely the same as below)
CP-11, PS-20, PS-30
YM10020
PSC
"Parallel Serial Converter"
DIP16 weird thing with negative logic and 1-bit serial streams. 1970-ties style emitter-coupled logic (ECL)
CN-70
YM1008
GH1
"Generator, Handy Sound-1"

HS-200
YM1011
KAR
"Key Assigner & Rhythm" DIP40
CP-11, ?PS-30
YM10150
DTG
"Key Coder Tone Generator"

CS-01
YM10180
GH2
"Generator, Handy Sound-2"

HS-500
YM1019 (pinout) GE4
"Digital Tone Generator - 4"
Wave generator / synthesizer
MP-1, PC-50, PC-100, PS-400
YM1020
IE
"Intelligence Electone"
PlayCard processor
PC-50, PC-100
YM1032
KAP

Keyboard control processor, on these eary models called "Key Assigner"
PC-50, PC-100
YM1034 (pinout) KAP2

Keyboard control processor, on these eary models called "Key Assigner" MP-1, PS-400
YM1035
(pinout)
SECIII
"Symphonic Ensemble Clock Generator-III"
also "Tremolo Clock Generator III"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM1038 MIE?


PC-50
YM1101
DOM
"Digital Tone Generator" DIP40
CP-11, PS-20, PS-30
YM11010
DOM
"Digital Tone Generator"

CN-70
YM1102


DIP24
PS-20, PS-30
YM1104 (pinout)
(CerDIP beauty)
GE2
"GE II (Generator 2)" Somewhat self sufficient simple preset 8-voice keyboard chip with a few automatic accompaniment variations in beautiful ceramic DIP48, that needs external switchable timbre filters for tones (similarly to transistor organs, for example). Also typical to transistor organs is the way how vibrato applied - just by detuning the master clock (which gives it the extremely cheesy cheap vibe since it applies to all voices, including accompaniment). PS-2, PS-3, PS-10
YM1105
(pinout)
GE1
Generator 1
Simplified version of GE2 missing auto-accompaniment logic.
PS-1
YM1823
YM1823B
Sharp MS1823B
(OPLL YM2413 datasheet)
(use in Philips PMC-100)


Rather simple 2-op FM soundchip with preset tones (built-in instrument rom) in DIP18, apparently very similar to OPLL/OPLL-X (YM2413/23) or even exactly the same besides some register and/or rom differences. Pinout matches OPLL exactly, as well as having six voices (not counting rhythm) according to philips service manual. Also the part name YM1823 is in that service manual, along with another MS1823 designation - YM might be errorneous since there seem to be no other YM18xx, but I included it here anyways. (for now)
Philips PMC-100
YM2003
OP2
"Operator"

YP-40
YM2005
KAS
"Key Assigner"

YP-40
YM2021
(iT202100)
YM20210
KAP3
"Key Coder & Assigner for PS"
Keyboard control processor, on these eary models called "Key Assigner" PS-25, PS-35, PS-55, CN-1000
YM2022
(iT202200)
GE5
"Generator"
Interesting 9-voice PCM wavetable synthesizer. Uses external (up to) 4kbyte ROM with tiny sample loops and instrument parameters: each tone record is 64 bytes long and contains 32 wave points (8-bit signed) that get unfolded (reverse&invert) into 64; the rest of the record are parameters. Requires external DAC through custom serial bus.
PS-25, PS-35, PS-55, CN-1000
YM2023
(iT202300)
RYP2
"Rhythm for PS"
Supports up to 64kbyte WaveROM with samples in exactly the same log8bit format as RYP4. Uses huge external parallel exponent-mantissa DAC (iG09560).
PS-25, PS-35, PS-55, CN-1000
YM2025
(pinout)
SC
"System Controller"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2114
(pinout)
SCI
"System Control Interface"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2115
(pinout)
PG
"Phase Generator"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2117
(pinout)
OPB
"Operator-B"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2118
(pinout)
OPC
"Operator-C"
Used in loop with OPCW
FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2119
(pinout)
DGF
"Degital Filter"
Interesting chip, that can be loaded with arbitrary IIR coefficients
FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2120
(pinout)
DACL
"DAC Logic"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM21210
(pinout)
DRV

Serial to parallel converter for panel LEDs
FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2122 E
REV
"Reverb"
A 20bit reverb DSP in DIP-40, running at 9.6MHz. Internally does 37 delay stages, each fed by input added with its own attenuated output, and this input sum is also the output of each delay stage. Sounds surprisingly good, despide it's age (~1982).
FX-10, FX-20, R-1000 (1U reverb unit, not the receiver with the same name)
YM2123 REVI
"Reverb Interface"
FX-10, FX-20
YM2124
(pinout)
OPCW
"Operator-CW"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2127
(pinout)
TE
"Touch Envelope"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
YM2128, YM21280
(photo)
OPS
"OPS Operator"
DX-7, TX-7
YM2129, YM21290
(photo)
EGS

envelope generator DX-7, TX-7
YM2142 GE8

Simple polyphonic 4-voice+rhythm pre-FM age sound chip with 6 analog outputs.
PCS-30, PSS-150, PSS-160
YM2148
MKS
"MIDI interface and Key Scanner"

CX-5MII
YM2149 (datasheet) SSG
"Software-Controlled Sound Generator"
Classic chip, clone of AY8912, used in ZX Spectrum, Atari-ST, MSX e.t.c.
CX-5M, CX-5MII, CX-5MU
YM2151 (datasheet) OPM
"FM Operator Type-M"
8ch 4op FM, used in many arcade machines (Atari, Sega, Konami etc), also as built-in FM synth in some MSX machines and expansions for it
CX-5MII, CX-5MU, SFG-01, early SFG-05
YM2154
(IT215400)
RYP4
"Rhythm Generator"
Very interesting rompler chip, that uses oddball custom serial roms (YM2190), 2x 6voices. Samples in roms are in exactly the same log8bit format as was in RYP2. Each half can use only it's own dedicated ROMs, so the polyphony usualy is 6voices for percussion and 6voices for base.
Requires external DAC - YM3010 or YM3012.

Jari Kangas did an amazing job reverse engineering and documenting this chip here:
GitHub PSR-70 reverse

Local mirror: RYP4 Programming PDF
CVP-3, DSR-2000, HS-8, PS-6100, ?PSR-50?, PSR-60, PSR-70, PSR-80, PSR-90, PSR-6300, RX-11, RX-15, RX-17, RX-21, RX-21L
YM21552
(IT215520)
GHS-5

Entire kid keyboard in a single DIP16 chip.
TYU-20
YM21568

Small serial ROM in DIP-8, used in music data cartridges for TYU-30, containing ten songs each. This little serial ROM uses a custom interface consisting of sync, continuous clock and data in/out, very similar to their chip-to-chip serial interfaces for DSPs of the time. It's just 4kbytes in total, and that's also the addressing limit of both its serial protocol and cartridge header data. Songs are uncompressed and 350 bytes on average, peaking out at over 481 bytes for the largest one ("La Paloma"). And there's even 302 and 373 bytes left free that could have fitted one more song on each cart. While song size is very similar to PlayCards, data is completely different and in no ways compatible without some reprocessing and conversion. However, since song data looks very familiar to me and of the PSS-104/103/etc flavor, conversion support is very likely to happen some day. Thanks to the great work done by Ian Wang of demodb.org we now have proper dumps of both cartridges!
TYU-30 ROM PACK A
YM21569

Cartridge custom serial ROM with ten songs. See YM21568 above.
TYU-30 ROM PACK B
YM2159
LPD
"LED Driver"
Led array driver for panel indication
CVP-3, CVP-20, CVP-50, DSR-1000, MR-500, PSR-90
YM2160
OPCW2
"Rhythm Operator"
FM drums synthesizer
MR-500
YM2162
(IT216200)
CRI


CVP-8, MR-500
YM2163


Info only from Cyberyogi, have not seen it myself. 4-channel soundsource.
Testron CL-60910
YM2164
OPP
"OPP Operator"
Used in IBM MFC sound card as well. Has a very nice round and smooth sound, and uses external stereo DAC for it's output (YM3012)
CVP-3, CX-5M, DX-21, DX-27, DX-100, FB-01, MR-500, PS-6100; later SFG-05, also Korg DS-8 and Korg 707
YM2165 (Y2165)


Small serial ROM in DIP-8, used in music data cartridges for TYU-30. Chip with this designation is seen inside actual cartridge on a photo by Tim Milkfloats. Curiously, service documentation states that cartridges should contain YM21568 or YM21569. I haven't seen it myself, yet. Interface may be similar to the YM2190: bitclock, sync, addr to rom (a0..aN), data from rom (d0..d7). If I will someday get my hands on a TYU-30 with cartridge(s), I will read them out and post data and format there. This might allow to make an improvised MIDI interface cartridge, with access to all song multitimbrality features, custom or converted songs etc.
TYU-30
YM2188-x


Serial drum roms most likely, but haven't yet checked those in life.
RX-21, RX-21L
YM2190-1
(YM21901)
ROM

32kbyte drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). Contains only ride cymbal.
RX-11, ?RX-15?
YM2190-2
(YM21902)
ROM
32kbyte drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). Contains only crash cymbal. RX-11, ?RX-15?
YM2190-3
(YM21903)
ROM
32kbyte drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). Contains hihat, cowbell and claps. RX-11, ?RX-15?
YM2190-5
(YM21905)
ROM
32kbyte drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). Contains a variety of bass and snare drums, rimshot and tom.
RX-11
YM2190-6
(YM21906)
ROM
32kbyte drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). Contains alternative hihat, cowbell and claps. RX-11
YM2190-7
(YM21907)
ROM
32kbyte drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). Contains one bass, two snares, rimshot, shaker and three toms. RX-11, ?RX-15?
YM2190-8
(YM21908)
ROM

Drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). 32kilobytes of samples in log-8bit. ?PSR-50?, PSR-60, PSR-70
YM2190-9
(YM21909)
ROM

Drum and percussion waveform ROM, that utilises an unusual custom serial bus intended for RYP4 (YM2154). 32kilobytes of samples in log-8bit. ?PSR-50?, PSR-60, PSR-70
YM21910
YM2191
(iT219100)
KAP3
"Key Coder & Assigner for PS" Same as YM2021; mentioned as a compatible replacement option.
CN-1000
YM2192
(iT219200)
GE5
"Generator"
Same as YM2022; mentioned as a compatible replacement option. CN-1000
YM2193
(iT219300)
RYP2
"Rhythm for PS"
Same as YM2023; mentioned as a compatible replacement option CN-1000
YM2198
KAS
"Key assigner"

YP-40
YM2203 (datasheet) OPN
"FM Operator Type-N"
3ch FM + 3ch SSG + 1ch Noise
Arcade machines
YM2214
(iT221400)
GHS-6

Interesting early kid keyboard on-a-chip that supports serial cartridges (with song data) that use a bus typical for electones and their early dsp systems (sync, clock, di and do).
TYU-30
YM22600

"Pedal LSI"

D-30
YM22700
"8 Rhythm" "Eight Rhythm LSI"

A-60
YM22800

"Fourteen Rhythm LSI"

D-30
YM22900
"ABC Pattern Generator LSI"

A-60
YM23000
"ABC Main"

A-60
YM2406
(XA804001)
DFL
"Digital Filter"

EL-40, EL-60, HE-5, HS-5, HS-8
YM2409
(XB022001)
GEW1
"Generator of Wave 1"
Supports up to 4Mbyte of WaveROM and seems to support multiple chip configuration and mixing through digital serial audio inputs/outputs. Uses external YM3021 DACs.
AVS-10, CVP-8, ?TX-16W?, RX-7, Electone HE-5, HS-8
YM2410
(XA903001)
GE10

Minimalistic single chip toy synth. Just plain squares, non-FM/PCM. Surprisingly compact (with respect to it's functions) DIP24 package.
PSS-30, PSS-120, PSS-130
YM2412
ADF
"Adaptive Digital Filter"

CVP-8, ?TX-16W?
YM2413 (datasheet) OPLL
"FM Operator Type-LL"
Used in MSX (expansion) and Sega Mark 3
PSR-6, PSS-140, PSS-170, PSS-270
YM2414(B)
(XB768001)
OPZ
"OPZ Operator" Excellent Sega Megadrive-ish tone generator. Requires external DAC - YM3012. Electone HS-8 has five of these inside (besides GEW1), as well as mysteriously CVS-10 has two of these as well - likely those are used for percussive attacks for each voice, since the body of module's organ voice is made up from 9 components (sine and something else) which is obviously too much for 4-op fm. I will definitely look into this at some point.
CVP-8, CVS-10, DSR-1000, DSR-2000, DX-11, EW-20, HE-5, HS-5, HS-8, PSR-80, PSR-90, PSR-6300, TQ-5, TX81Z, YS-100, YS-200
YM2416(B)
XD082001
(pinout)
GE11

Sampling keyboard enirely self-contained controller with internal ROM and includes sampling ADC and DAC, requires external DRAM for user sample storage. Sampling is plain 8bit PCM. Unfortunately program rom is internal and there may be no ways to control or explore it besides key matrix. VSS-100 uses a better solution - MSX AUDIO chip. VSS-200 is a bizzare contraption, that to somehow expand the single chip toy keyboard (well essentially the VSS-30) has additional master cpu (unfortunately mask rom HD6301) that uses a separate gate array to control the toy keyboard through its keyboard controls... Also since fine tuning cannot be done with GE11, there is a kludge with cpu using a 4bit resistor DAC to adjust GE11 clock vco. That VSS-200 is one weird piece of misengineering!
VSS-30, VSS-200
YM2420
(XD211001)
OPLL-2
"FM Operator Type-LL2"
PSS-140, SHS-10
YM2423 OPLL-X
"FM Operator Type-LL-X"
Mentioned to be with the same pinout as YM2413, but haven't seen these myself.
FM Melody Maker (for Atari ST), Philips PMC100
YM2424
OPZ2
"OPZ2 FM Tone Generator"
V-50
YM2603 ESG2

generates envelopes, lfos and controls for OPS2
PF70, PF80
YM2604
OPS2
"FM Operator Type-S"
PF70, PF80, TX-802
YM2608
OPNA

FM+SSG+ADPCM chip

YM2610 (pinout) (translated datasheet) OPNB

FM (4x4op) + SSG (3voice) + Noise + 7x ADPCM in one massive ShrinkDIP64 package.
NEO GEO
YM2612 (a_lot_of_info) OPN2

Used in Sega MegaDrive/Genesis and some arcade machines, and is my absolute favourite.
There exists a perfect clone of this chip called SE-95, which can be found in Sega Megadrive 1 clones.
Sega Megadrive and
Genesis
YM3010
DAC
"2-Channel parallel input floating D/A converter"

RX-11
YM3012
(IT301200)
(datasheet)
DAC-MS,
SUX DAC
"Floating D/A Converter"

CVP-3, CVP-8, CX-5MII, CX-5MU, DSR-1000, DSR-2000, FB-01, HS-8, MR-500, Korg 707, PSR-31, PSR-80, PSR-90, PSS-570, TX-81Z
YM3014
DAC

Only for RYP-6
PSR-31, PSS-560, PSS-570
YM3016
DAC



YM3017
(XA800001)
DAL2 ver.1
"DAC Logic"

EW-20 (with s/n 01101 to 04100), HE-5, HS-5, HS-8, TQ-5, V-50, YS-100, YS-200
YM3020
(XA860001)
DAC-FS
"Serial & Binary input Floating D/A Converter"
yet another 2ch crappy mantissa&exponent dac
AD-808, DEQ-7
YM3021
(XB073001)
PSD
"Pitch Sync DAC"
Used with ADF chips.
CVP-8, RX-7
YM3028
(XE789A00)
(pinout)
DAL2
"Digial Analog Converter Logic"
AVS-10, CVS-10, EL-40, EL-60
YM3028A
DAL2 ver.2
"DAC Logic"

EW-20 with s/n over 04100
YM3029
AFD0
"Floating point converter"

RM-50, SY-55, SY-99
YM3030
(XG075A00)
DAC

Mono DAC
KB-100, PSR-7, PSR-8, PSR-47
YM3032
DAL3
"Digital Analog Converter Logic"

PSR-6700, SY-22, SY-35
YM3301 (pinout) RYP6
"Rhythm Generator 6" Contains full rompler logic, drum waveform mask ROM and some output formating logic for external serial dac.
PSR-31, PSR-32, PSS-560, PSS-570
YM3302
RYP6
RYP6-2
"Rhythm Generator 6"
Same pinout as YM3301, except for pin14 being renamed from A0 to RS (register select).
DD-10, DSR-1000
YM3404(B) (datasheet) CDDF
"Oversampling Digital Filter" Boring, as FIR coefficients are stored in internal mask ROM. Likely used only in some CD players.

YM3413
(XE449A00)
LDSP
"L-Digital Signal Processor"
also "Sound Field Creation DSP"
Reprogrammable 16-bit DSP effects processor for hall, room and delay. Uses external 32kbyte (rarely 64kbytes - for example in FX-900) SRAM, and can address up to 128kbytes. Sounds surprisingly good for its looks (DIP-40). Programs are only 32cycles long, and generaly all rooms and halls use 9 delays with most using two taps. Supports 4 channels for input and output, though usually only one channel is used for send and stereo pair used for return.
AVS-10, CVP-50, CVS-10, DSP-E1000, EL-40, EL-60, EME-1, EW-20, FX-500, FX-900, PSR-220, PSR-230, PSR-500, PSR-510, PSR-5700, PSR-6000, PSR-6700, R100, SY-22, SY-35, SY-55, SY-77, TG-33, TG-100, TQ-5, V-50, YS-100, YS-200, CLARION DSP-959
YM3414
ACDDF
"Oversampling Digital Filter"
Boring, as FIR coefficients are stored in internal mask ROM. Likely used only in some CD players.
YM3415
(XE450A00)
LEF
"Effector"
"L-Effecter" (sic)
Digital reverb. Uses external 32kbyte DRAM.
FX-500, HE-5, HS-5, PSR-5700, PSR-6700, SY-77
YM3415B
(XE450B00)
LEF
"Effecter" (sic)

AVS-10, CVS-10, FX-900, PSR-6000
YM3419(B)
(XF026A00)
RYP7

Drum rompler that uses external 8bit parallel rom. It supports both 8bit linear and 12bit packed waveform data formats. Supports stereo panning, and up to 63 waveforms in 512kbytes or less. Has an internal stereo DAC and 4 channel slow ADC. A rarely used feature of this chip is a /GateEnable output on pin50. It is not documented, yet operational. This pin is used to suppress noise (by controlling FETs) but only in first "pilot" run of PSR-36.
DD-6, PSS-480, PSS-680, PSS-780, PSR-36, PSR-47, PSR-48
YM3420AD and YM3420BF
(YM3420BF pinout)
OPU
"CPU and FM Tone Generator"
FM tone generator along with some 8-bit CPU, RAM, ROM, MIDI interface UART and a DAC. Program in PSS-480 uses external gate array to switch ROM pages, as it can only address 64k. PSS-480 has 288kbytes ROM for program+demo+styles, while in PSR-16 and 36 there's only 16k and 32k bytes for everything respectively. DSR-500 has 32kbytes of ROM and 2kbyte of external RAM. DSR-500, PSS-480 and PSR-16 use mono FM output and only drums from RYP7 (on PSS-480) can be panned. OPU chip has 256bytes of internal RAM and 16kbytes of internal ROM.
Tiny RAM size pretty much explains the capacity of sequencer in PSR-16.
Versions AD and BF slightly differ in their pinouts. YM3420 AD version is in PSR-16, and seems to have slightly higher audio quality.
PSS-480, PSS-680, PSS-780, PSR-16, PSR-36, DSR-500
YM3422
(XE862001)
ES1
"Format Converter"
DAC Format conversion chips
DSP-E1000, FX-900, SY-99, CLARION DSP-959
YM3422B
(XE862B00)
ES1
"Format Converter" DAC Format conversion chip MU-80, P-100, P-150, PSR-7000
YM3423
(XF031A00)

YM3423A
and somehow also YM7104
(XF779A00)
GEW3
"Generator of  Wave"
"AWM Sound Source & Digital Filter"
Supports up to 4Mbyte waverom, but doesn't seem to support waveform sample loading. Seems to be the last GEW to support 4-bit compressed wave data besides the yamaha typical 8bit signed.
CLP-550, CLP-650, CVP-20
YM3424
(XF027A00)
KPU
KPU1
"Key Processing Unit"
"Key Assigner & CPU"

CLP-650, CVP-20, CVP-50
YM3427
(XF778A00?)
(XF357A00)
GE12

Square/snippet-wave synth with analogish drums. Unusually, it uses SPI-like serial port for control. Has an internal mono DAC.
PSS-80, PSS-100
YM3433, YM3433B (datasheet) ALCDF
"Oversampling Digital Filter"
Unfortunately, FIR coefficients are in internal maskROM
CLARION DSP-959
YM3434
(XG610A00)
(datasheet)
AFUDF
D.FIL
"Oversampling Digital Filter"
"Over sampling Digital Filter"
Unfortunately, FIR coefficients are in internal maskROM FX-900
YM3436
DIR2
"Digital format interface receiver"

AW16G, DS2416 (PCI DSP Factory card), SREV1, CLARION DSP-959, SB-168
YM3436DK
(XG948E00)
DIR2
"Digital format interface receiver"
AIEB2, SPX-2000
YM3437 DIT2
"Digital format interface transmitter"
AW16G, SREV1, UD-STOMP
YM3437C-F
(XM530A00)
DIT2
"Digital Format Interface Transmitter"
AIEB2
YM3438
OPN2C

6 channel, 4 operator FM. Used in some Sega arcade machines, as well as FM-Towns II

YM3439


FM chip used in Atari Falcon 030

YM3440
(XH238A00)
(pinout)
LEF2
"L-Effector"

EL-40, EL-60
TMC3489NL
(I assume it fits here)
XE755A0(0)
SFC
"Signal Format Converter"

AVS-10, CVP-50, PSR-6700, SY-22, SY-35
TMC3493PH
(I assume it fits here)
XF987A0(0)
GEW5
"AWM & FM Tone Generator"
Very interesting chip that supports unlimited cascading through special cascading in/out bus and external sync. Two chips can share a single waverom set using time domain multiplex. Four and even five of these chips can comfortably sit together and produca a very nice sound (TG-33 and PSR-6700 being the case). Supports up to 2Mbyte of wave data. FM capabilities appear to be designed similar to OPU chip. Supports sample loading, if static RAM is conneted instead of ROM. Sample format is yamaha's future dominant - signed 8bit linear.
CVP-50, KB-100, PSR-7, PSR-8, PSR-27, PSR-37, PSR-47, PSR-48, PSR-3500, PSR-6700, SY-22, SY-35, TG-33
YM35100

"Low Noise 512 Stage BBD"

FX-10, FX-20
YM3514
IEF

Since otherwise PCS-30 contains generic Z80 and a normal sound chip, this one (that so far didn' t pop up anywhere else) might be some of their controller chips repurposed as a playcard reader peripheral, led and key scanner for Z80... I will look at it in some near future.
PCS-30
YM3526 (datasheet) OPL
"FM Operator Type-L"
Used in arcade machines and C-64 FM exapnsion cart.

YM3533 OPQ
"OPQ operator" Seems to be the same as YM3806. Very interesting 8channel FM chip, that seems to have an unusual sound character for some patches and some unique sounds. It has some unique tricks up it's sleeve.

Jari Kangas did an amazing job reverse engineering and documenting this chip here:
GitHub PSR-70 reverse

Local mirror: OPQ Programming PDF
PSR-60, PSR-70
YM3602
OPRW
"OPRW Operator"
Despite it's name, it's a PCM rompler chip for rhythm part.
V-50
YM3603
(XA805001)
(pinout)
KBS, KBS1
"Keyboard Scanner"

EL-40, EL-60, HE-5, HS-5, HS-8, MKX-5
YM3604B


CVS-10
YM3608
(XA895A00)
DEQ
"Digital Equalizer"

DEQ-7, REV-5
YM3609
EGM


TX-802
YM3623(B)
DIR
"Digital Audio Interface Receiver"
DIP28 chip with internal vco
AKAI S3000XL, Luxman LV-113
YM3801 MSX AUDIO

It is quite a cool chip with FM synth and sampling using external DRAM. Only VSS-100 has it, while VSS-30 and VSS-200 use strangely specific single chip toy keyboard solution GE11.
VSS-100
YM3802
MCS
"MIDI Communication & Service Controller"
It's a slow UART, but with built-in FIFO and MIDI clock tick output (pulses SYNC pin on every received $F8). Has also metronome tick output, which is just a divided midi clock pulse. An unusual use for these chips has also been reported by a reader Maxim Vlasov: Yamaha MSX-series computers YIS-805/128R2 use them for local networking!
MSX YIS-805/128R2, RX-5
YM3804
(IT380400)
DSP
"Digital Signal Processor"
DSP in 64-pin shrinkDIP, uses DRAM, supports up to 192kbytes.
CVS-10, DEQ-7, FX-900, HS-8, REX-50, REV-5, REV-7, SPX-90
YM3806
OPQ
"OPQ operator"
Seems to be the same as YM3533, see above.

Jari Kangas did an amazing job reverse engineering and documenting this chip here:
GitHub PSR-70 reverse

Local mirror: OPQ Programming PDF
CLP-100, PSR-70
YM3807
(XA902001)
MOD
"Modulation Data Generator"
Provides modulation lfo source to YM3804.
FX-900, HS-8, REX-50, REV-5, REV-7, SPX-90, SPX-900
YM3808
(XA798001)
MIX
"Digital Mixer"

CVP-50
YM3809
(XA796001)
RFL
"Re Sample Filter"

Electone HE-5, HS-5, HS-8
YM3812 (datasheet) OPL2
"FM Operator Type-L2"
Adlib classique
PSR-11, PSR-12, PSR-21, PSR-22, PSR-31, PSR-32, PSS-460, PSS-470, PSS-560, PSS-570
YM3813 MPH
"Micom Peripheral Hardware"

MKX-5
YM3818 DSPM
"Digital Signal Processor"

C20, YDG-2030, YDP-2006
YM3901
(XC282001)
ADA

AD/DA converter support chip
DEQ-7, R100, REX-50, REV-5
YM3907
ADG

Wave Address counter array. Very typical design for 80-ties romplers when synthesizer DSPs were devided into several chips. This is the first stage, that determines pitch and just counts addresses. 64-pin package.
RX-5
YM3908
WDP

Wave data processor, that does interpolation and scaling. For it's 14 (probably planned for 28?) voices it uses 14 independant DACs (YM3014). 64-pin package. RX-5
YM3931


PCM rompler in 64 pin shrinkDIP, used in some arcade machines

YM3934 PMM2
"Peak Meter Module"

C20
YM5107 SRB "Shift Register Bank" Special memory for dsp write control store (2x 16bit x128). REV-1
YM5203
(pinout)
SCD
"System Control Decoder"

FS-50, FS-70, FX-10, FX-20
YM5210
DPAP
"Double Precision Arithmetic Processor"
Interesting powerful (for the time) dsp mac unit (16x16bit multiply into 36bit accumulator).
REV-1
YM5211 PMM
Peak Meter Module
Peak meter for16bit digital audio, outputs 2ch 8bit log (for dB).
REV-1
TMC57800N
MIX5
"Mixer"
Digital mixer to mix several GEW-5.
PSR-6700
YM6007
(XF164A00)
DSP2
"Digital Signal Processor 2"
Remarkable for having up to 28-bit sample precision delay memory.
SPX-900, SY-99
YM6029
(XH746A00)
DPB
"Digital Patch-Bay"

FX-900
YM6045(C)


Sega Mega Drive / Genesis early chipset, also known as 315-5364

YM6046


Sega Mega Drive / Genesis early chipset, also known as 315-5309
YM6071B
(XH747A00)
PMM3
"Peak Meter Module"

FX-900
YM60800

"String Ensemble Clock Generator"

FX-10, FX-20
YM6104
(XE788A00)
DEQ2
"Digital Equalizer 2"
Programmable digital EQ chip with programmable coefficients (internal RAM 128 words).
C20, FX-500, FX-900, MU-80, SPX-900, YDG-2030, YDP-2006, CLARION DSP-959,
YM6633
(XH543A00)
KSN

Velocity 88-key keyscanner
P-100, P-150
YM7101
VDP

VDP in Sega Genesis / Mega Drive, also known as 315-5313

YM7102
(XG996A00)
PAN


SY-77, SY-99, W-5, W-7
YM7103 EGM2


SY-77, SY-99
YM7104
(XF779A00)

(somehow also YM3423)
GEW3
"Generator of Wave"
Possibly the same as YM3423 but in a different chip package, or something.
CVP-50
YM7107 OPS3


SY-77, SY-99
YM7108
(XF355A00)
GE13

Entire squarewave+drums+accomp minimalistic synth in one tiny DIP18 package.
PSS-20
YM7116
(XG286A00)
(pinout)

(finally a PSS280 shematic)

My research info on OPK and OPK2
OPK
"OPK"
8 channel stereo FM synth, with integrated PCM drums and DAC. DIP18. Although these keyboards are not rare and are frequently found circuitbent, there was totaly no information about these chips anywhere what so ever.  Even regarding existence of OPK. Hooray - now there is! I also have captured all the data being written to the chip and reverse engineered a lot of it. PCM samples are with heavy dynamic compression and envelope gets added on the fly. PSS-280, PSS-290
YM7119 (pinout) M3
"AWM Tone Generator with Digital Filter"
Giant 128pin chip, seems rather experimental, as it has a lot of "test pad" pins (at least 12) or no connect ones (at least 13).
Seems to be completely reprogrammable (no internal ROM)
RY-30, SY-55, SY-77, SY-99
YM7121C
SPC V
"Signal Processor & Controller & RAM for CD Player"
CD pickup servo control, efm demod, fec, jitter attenuator. Not a synth chip.

YM7126




YM7128(B) (datasheet) SP2
"Surround Processor"
Can also do simple reverbs, has a miniature ram on die, operates in yamaha-style weird samplerate: 23.6kHz

YM7129 (pinout)

My research info on OPK and OPK2

OPK2
"OPK2 Operator"
8 channel stereo FM synth, with integrated PCM drums and DAC. DIP18. Although these keyboards are not rare and are frequently found circuitbent, there was totaly no information about these chips anywhere at all.  Even regarding existence of OPK. Hooray - now there is! I also have captured all the data being written to the chip and reverse engineered a lot of it. PCM samples are with heavy dynamic compression and envelope gets added on the fly.
PSS-26, PSS-101, PSS-102, , PSS-103, PSS-104, PSS-280, PSS-290, PSS-380, PSS-390.
YM7131
(XH236A00)
(pinout)
OPLZ
"FM Tone Generator"
Did you knew such an OPLZ even existed? I haven't scoped/captued it, but it seems to be of the rare kind that outputs linear (instead of exponent&magnitude) digital audio.
EL-40, EL-60
YM7132
(XH235A00)
(pinout)
OPWZ
"AWM Tone Generator"

EL-40, EL-60
YM7133 (pinout)
LRV

An interesting 12-bit reverb DSP in DIP28 with integrated mono ADC and stereo DAC. Samplerate is rather high for what it is - 41.667kHz. Uses external DRAM (single 4bit x 64k chip) that it accesses in triplets to get 12bit/instruction. Algo uses just 31 instructions (+1 seems to be blank for dram refresh where no write or read occurs) per sample. WCS unfortunately is all in internal maskrom, so you have only a fixed algo with no parameters. Depending on how low it can go (and dram will refresh), perhaps it can be underclocked for grittier sound and longer reverb tails.
PSR-18, PSR-19, YPR-30
YM7137 (pinout)
(typical usage schematic)

YM3137 (XH242A00)

YM3137-3D (XI257A00)

YM3137-4E (XI262A00)

YM3137-5F (XJ292A00)

YM7137-6G (XK208A00)
OPJ
"OPJ Operator"
CPU + FM + PCM drums. While considered by many to be a stubborn unbendable all-in-one chip, I managed to find an access to it's soundsource, which I was digging back in the day to use in a first-of-a-kind OPJ sound module. It is rather similar to OPK, but OPJ's builtin CPU firmware lacks any realtime assistance stuff that allows OPK synths have more live, fun and dazzling sounds.
There are at least five maskrom versions: first, 3D, 4E, 5F and 6G. There probably should have been something like 1B and 2C as well, but haven't stumbled upon those yet. 4E is only used in the keyboards with 61 key and "digital signal processing" feature. The only thing added is "reverb" and "echo" button controlled toggling of two output pins for LRV reverb chip.  There are also some key scan pin differences between 3D and 4E. Version 5F is found only in PSR-100.

I am planning someday to kludge up a page, devoted to OPJ hacking. Not sure when, though.
PSR-2, PSR-3, PSR-18, PSR-19, PSR-100, PSS-9, PSS-16, PSS-50, PSS-190, and other (if any) FM keyboards with "Ad-lib" button.
YM7138 GEW6
"AWM Tone Generator & D/A converter"
Rompler, capable of addressing up to 4Mbyte of 12-bit packed or 8-bit linear wave data, single sample size limited to 64kpoints. Decompressing (unpacking) 12-bit/sample data feature looks nice, but it has otherwise very limited processing capabilities and has limited single DAC with 4 channel (selectable only on/off) analog mux system built-in that cannot pan sounds gradually. Its 4 ch muxed DAC is primarily used as hard wired four fixed pan positions or can also be used as dry and fx sends (same as in OPU). LFO (at least for pitch) and even envelopes seem to be handled in software (usually via matsushita/panasonic cpu) and pitch & level gets updated at about 80Hz or something. There's no dsp parameter smoothing engine for smooth updating, so envelopes do audibly buzz. Volume multiplier is also very improvised - something like 12x5bit. I wouldn't call it a real DSP. It uses 16 clocks for every voice to be calculated - so it rather definitely does multiplication using sequential shifts and additions.
However, it also has an FM tone generator capabilities, as well as sample loading (if wavesram present on board) feature which doesn't seem to be ever used (besides at synth development).
DD-11, PSS-590, PSS-595, PSS-790, PSS-795, QY-10

YMF, YMM, YMW series

IC name
Yamaha's alias
Yamahas official short description My notes
Used in
YMF262
OPL3

Legend in default PC sound of early 90-ties.

YMF278B
OPL4
"FM+Wave Table Synthesizer LSI"
There is something very GEW6-ish in it. It's different, but there are notable programming, format and stucture similarities.

YMF281B
YMF281B-D
OPLL-P



YMF704B-S
YMF704C-S
OPL4-ML
"FM+Wave Table Synthesizer LSI"
Single chip solution of a very simple general midi compatile synth. Used on tiny "Creative WaveBlaster - compatible" boards for PC sound cards. Contains 1Mbyte of wave data and an OPL-3 compatible chip.

YMF709
XT997A00
OPOS
"OPOS"
Odd 8-voice FM synth chip in DIP24, uses YM3012 dac.
HD-100
YMF711
OPL3-SA2
"OPL3 Single Chip Audio System 2"
Boring ultra-integrated sinle-chip solution for ultra-cheap PC soundcards.

YMF715
OPL3-SA3
"OPL3 Single Chip Audio System 3" Boring ultra-integrated sinle-chip solution for ultra-cheap PC soundcards.
YMF724 DS-1

Boring ultra-integrated sinle-chip solution for ultra-cheap PC soundcards with PCI slot.

YMF730 AC-2

Integrated ADC, DAC, mixer and S/P-DIF interface for PC sound cards.

YMP706-F
(XT329A00)
FS1, FS1-AB
"AWM Tone Generator & Digital Filter"
Used for FM and "formant" synthesis.
DX-200, FS1R, PLG150-DX
YMW258-F
(XJ427A00)
(pinout)
GEW8
"AWM & FM tone generator"
PCM+FM 28 voice dsp, that renders waves quite nicely.
It seems it was designed as a high end sound source of the time, and requires 18bit external DAC. For sound modules with reverb, there is special port (pin26..31) to connect optional LDSP (YM3413).
Wave memory can be up to 4Mbytes. Sample loading is supported, but it then requires large amounts of static memory (along usual waverom). Supports both 8bit and 12bit wave formats.
MU-5, PSS-51, PSR-82, PSR-200, PSR-210, PSR-215, PSR-300, PSR-310, PSR-400, PSR-410, PSR-500, PSR-510, PSR-600, QR-10, QY-20, TG-100
YMW258B-F
GEW8S
"AWM tone generator"
Seemed to be just 3.3V version of GEW-8, but it's still powered from 5V, so there's some other differences yet to spot out.
PSR-320, PSR-420, RY-9,

?PSR-600, ?PSR-210, ?PSR-215,

? - means I am not sure about those ones regarding 5V or 3.3V
YMW259-F
GEW9
"AWM Tone Generator & Digital Filter"
38? (for P pianos it is 32) voice polyphony oldschool beastie. Uses external, standard DACs (in case of PSR-5700 - analog devices AD1862) as well as need external effects processors (like LEF and LDSP). Given it is used with 11.727MHz, presumably it uses 7 clocks per voice (7x38) for 44.1kHz, but it needs to be checked in hw.
P-100, P-150, PSR-5700, PSR-6000
YMW266-F
(XK817A00)
M3B

Rare, and therefore interesting, but still just an AWM rompler - so equally boring. It was designed as a high end thingy, with ability to address up to 32Mbyte of 16bit wide waverom.
W-5, W-7
YMW270-F
(XK328A00)
(pinout)
GEW7
"AWM Tone Generator and DAC"
8-bit CPU and RAM (~256 bytes total), combined with a 14-voice hardware multichannel rompler. Rompilng part seems to be a cut down version of GEW6. There is no built-in UART for MIDI, unfortunately. Samples are in linear signed 8-bit format, however packed 12-bit format is also supported. Shared ROM space for program, styles, demos, lookup tables and samples. ROM address space is only 512kbytes, and what's worse - a single sample cannot be longer than 16kbytes. However it supports reverse playback that , as far as I've seen, never appeared to be used on actual keyboards with these chips.

Only used in keyboards with the "Music Mode Selector" knob. Grab the pinout file, as it was nowhere else to be found.

I have done some lot of successful disassemblies of the firmware, and also run those with modified code and did all sorts of bizzare fun.

I am planning to kludge up a page, devoted to GEW7/7S internals and firmware design. Be back in a while..
PSS-11, PSS-21, PSS-31, PSR-75, PSR-110, PSR-150
YMW275-F
(XN346A00)
SWP20
"AWM tone generator coped with MEG; Standard Wave Processor"
Monstrous (back then) chip with 32 voice polyphony and filters. Can be paired to double it. Supports sampling. Requires a bunch of accompying chips.
PSR-7000
YMW275B-F SWP20B
Seems pin-compatible and interchangable with the non-B version.
MU-80
YMW276-F
(XM732A00)
GEW7I
"AWM Tone Generator and DAC"
Odd and rare variation of ortherwise very popular low quality GEW-7. Although has the same pinout, and still 5V, but is stated as not interchangable with GEW7 and has some bugfixes regarding DAC outputs.
DD-9, DD-20, also later revisions of PSR-110
YMM279-F
(XN347A00)
SWD
"Standard Wave Decoder"
One of the accompanees for SWP20. Seems to do log-8 format sample decompression, however there could be more to that, since SWP20 passes 2-bit format number to this one, so there might be more - for example, it could be converting linear 8bit, log 8 and something else all into 16bit. Will likely probe around it one day and capture what it does exactly.
MU-80, PSR-7000
YMW282-F
(XP206A00)
(pinout)
GEW7S
"AWM tone generator with integrated DAC"
8-bit CPU and RAM (~256 bytes total), combined with a 12-voice hardware multichannel rompler. Rompilng part seems to be a cut down version of GEW6. There is no built-in UART for MIDI, unfortunately. Samples are in linear signed 8-bit format, however packed 12-bit format is also supported. Shared ROM space for program, styles, demos, lookup tables and samples. ROM address space is only 512kbytes, and what's worse - a single sample cannot be longer than 16kbytes. However it supports reverse playback that, as far as I've seen, never ever appeared to be used on actual keyboards with these chips.
A reader (Thank you, John!) reported that PSR-190 also uses this chip, although the keyboard looks like a downgrade of PSR-220 (that has  much better sounding GEW10), and recently I confirmed this myself as well - in both PSR-190 and it's mono variant - PSR-78.

This "S" version of GEW7 seems to only differ in lower system voltage (+3.3V instead of +5V) and altered pin48 bonding.

I have done some amount of successful tinkering with the firmware, and also run those with modified features and did all sorts of bizzare fun.

I am planning to kludge up a page, devoted to GEW7/7S internals and firmware design. Got this baby rather deeply reversed, down to sample and voice descriptors and program structure. Be back in a while..
PSS-6 (surprisingly), PSS-12, PSR-73, PSR-74, PSR-76, PSR-77, PSR-78, PSR-125, PSR-130, PSR-180, PSR-185, PSR-190
YMW703
(XR648A00)
GEW10
"AWM Tone Generator"
Has a general purpose CPU integrated, requires external DAC. Renders waves very well, and has nice sound (significanty better than GEW7 and GEW12). Sample formats supported are 8bit signed linear format and a then-new packed 12bit (incompatible with their classic 12bit) format.
PSR-220, PSR-230
YMW716
(XT332A00)
GEW11

Some realy weird, stripped down GEW (CPU+12voice_rompler+DAC) even with integrated ROM (I suppose 64 or 128kbyte) and all this in hilarious DIP-28. I am still searching for any info on them, as Yamaha does not seem to have any service info for these keyboards. Please let me know, if you have stumbled upon this chip in any other keyboard.
PSS-7, PSS-14, PSS-15
YMW717-F
(XS994A00)
GEW10-2
"Tone Generator"
While it seems just to be a minor change version from the YMW703 running from the same weird 29.411MHz clock, this one does 31 voice polyphony instead of 28 in the PSR-220&230.
PSR-330
YMW728-F
(XU355A00)
YMW728B-F
(XV762A00)
 (pinout and generic synth schematic)
GEW12

GEW12B
"AWM Tone Generator"
Conceptual, technical and spritual successor to the horrid GEW7S. However it is much better, with 4Mbyte (2Mword) address space (instead of 512k in GEW7) but still in 16kbyte pages for control cpu (that still has 64k address space), samples can br 64kbytes long instead of only 16kbytes, and it now features a built in MIDI UART and an integrated keyboard scanner with velocity sensing. Still sound is abominable (and ~27kHz samplerate is not to blame), partly due to intentionally lowpassed and crippled samples (even when not saving space: like for the crash cymbal, brass and certain strings -  just severely brickwall-lowpassed but still taking as much space as a full bandwidth sample).

Includes CPU and RAM. Shared 16bit ROMspace for program, auto-bass-chord patterns, song data, lookup tables and samples. Interestingly while actually it does 32 voices, those are used for pseudo-stereo sounds and dual patches, so that most synths are 16 voice. No dsp effects. Sample formats supported are 8bit signed and packed 10bit.

I have done disassemblies of the firmware and what not, and also run those with modified features and did all sorts of bizzare fun.

Such a lofi chip was a ridiculous surprise to find in a 76-key digital piano YPR-50, along with just a 1Mbyte rom for everything.
DD-35, EZ-150, EZ-20, EZ-J23, PSR-79, PSR-140, PSR-160, PSR-170, PSR-172, PSR-175, PSR-195, PSR-202, PSR-240, PSR-248, PSR-260, PSR-B20, PSR-GR200, PSR-J20, YPR-50; (as well as almost all other with round "DJ" button, except PSR-350 and maybe something else)
YMW767-V
YMW767-VT
YMW767-VTZ
?YMM757-VTZ
SWL01
SWL01T
SWL01B
"CPU & XG Lite Generator"
CPU with minimalistic hardware SWP-xx type synth.
No insert/aux effect, only reverb&chorus; 32-voices.

Not much fun at all. Just a bare minimum GM with additional sounds.
CP-33, DD-65, DGX-203, DGX-205, DGX-305, DGX-505, DGX-520, DGX-620, EZ-J24, EZ-200, EZ-250, EMX series, H-01, HD-200, KB-180, KBP-300, KBP-500, MM-6, MM-8, NP-30, P-70, P-85, P-95, P-140, P-140S, PSR-273, PSR-275, PSR-293, PSR-295, PSR-E203, PSR-E323, PSR-K1, PSR-R300,  PSR-S500, PSR-VN300, SKB-180, YPT-200

(YA876A00)
SWL01U
"CPU"

DD-45 (YDD-40), NP-V60, NP-V80,  P-35, P-105, PSR-E432
YMW830-V
(YE577A00)
YMW830-VZ
SWLL

Very minimal, Casio-ish chip, that boots from external high speed serial (quad-)spi rom, and is in an 80 pin package. Has an internal PLL that multiplies external 16.9344MHz clk to 67.7376MHz. There's also a JTAG port. There's a MIDI port as well (pin 54-out, 55-in cmos3v3 level).

Remie PCB has an unpopulated spot for usb controller.
PSR-F50, PSS-A50, PSS-E30, PSS-F30 Remie,
likely also PSR-F51
YMW832-CZ SWP70

This one is capable of incredibly fantastic sound. Uses NAND memory for waves, which is considerably concerning in regards to longevity of synth's life... though to fix it you may just need to do pcb rework of the chips and reflashing them. However, someone has to make working dumps for that to be a doable option.
MODX-6, MODX-7, MODX-8.


YA series

IC name
Yamaha's alias
Yamahas official short description My notes
Used in
YA3256


See below - IG12032
MK-100

YSD/YSF/YSP/YSS series

IC name
Yamaha's alias
Yamahas official short description My notes
Used in
YSD917
DIR5
"Digital Format Interface Receiver"


YSF207
(XI976A00)
(pinout)
DCF1
"Digital Controlled Filter"

EL-40, EL-60
YSF210
(XK280A00)

"8 time Over Sampling Digital Filter"

YDG-2030, YDP-2006
YSP99
LZ95D59
(XM047A00)


Gate array
FX-770, REV-100, REV-500, YDG-2030, YDP-2006
YSS203
(Xi022A00)
HL DSP


DSP-E1000
YSS205-F



SW-60XG
YSS208
(XI816A00)
DSPN
"Digital Signal Processor"

EMP-100, FX550, FX-770, P-100, P-150
YSS217(B)(-F)
DSP-V
"Digital Signal Processor"
DSP for "virtual acoustic" syntesis
PLG-100VL, VL1m
YSS225
EP

DSP for effects, I think I saw these used on some pc isa or pci boards.

YSS228-F
(XQ962A00)
DSP3

Effects DSP, also used in the PLG harmonizer board.
M3000, PLG-100VH, ProR3
YSS228D-F
(XQ962C00)
DSP3

REV-500
YSS228E-F

Used for effects and mixing
DS2416, SW-1000XG
YSS233-F
(XP268A00)
MDSP

Used for effects and mixing PLG150-AN,  PLG150-DX
YSS236 (-F)
(pinout and  schematic)
VOP3

Vocal harmonizer. Can also be used for other effects and filtering.
CVP-107, CVP-109, CVP-208, CVP-210, CVP-700, CVP-900, FS1R, PLG150-AN, PSR-740, PSR-2000,  PSR-2100, PSR-9000
YSS903 KP2V
"Karaoke Processor 2 for Video disc player"

YSS910(-S)
(XV988A00)
DSP6


01X, AW-16G, AG-STOMP, UD-STOMP, REV-1, SPX-2000
YSS915 KP2V2
"Karaoke Processor 2 for Video disc player"
Single chip immensly crappy karaoke echo and some very limited rudimentary pitch shifting. Besides digital audio bus i/o,  also has a built-in mono ADC and a stereo DAC.
Omnitronic DVP-36
YSS916CNV3

FIR convolver
REV-1
YSS919
(XZ693A00)
DSP7
"Digital Signal Processor"
Massive DSP in PQ-208 package.
01X, AW-16G, SB-168
YSS919B
(XZ693B00)
DSP7 "Digital Signal Processor"

SP2060
YSS928AC3D3


DPU-50
YSS952
(pinout and block diagram)
DSP2
"Digital Sound Producer-2"
Contains FM synthesizer and two tiny DSPs.
NS-WSW160


Custom Yamaha chips from miscellaneous chip fabs

IC name
Yamaha's alias
Yamahas official short description My notes
Used in

(XB810001)
SI-1

Serial interface for ROM/RAM cartridge slots. Some odball stuff from the electone times. As it seems, yamaha was then completely crasy about serial interfacing, even within a single board.
HS-8
JG541023
DDE1
"DAC Dynamic Range Enhancer"
probably the same vendor as iG
MU-90R, MU-100R
HD92098
(XM309A00)
MEG
"Multiple Effect Generator"
One of the accompanies for SWP20 in PSR-7000 and MU-80 for insert and system effects. Used also in the overcomplicated W-5/W-7.
MU-80, PSR-7000, W-5, W-7
HG73C201FD
(XT890A00)
SWX00
"Tone Generator"
Crappy sound of the DJX is related to the fact, that most, if not all, of the wave rom comes from terrible GEW-12 based keyboards - the ones with a black "DJ!" button. Or maybe it's oher way around... who cares. All the garish and lackluster samples like raunchy "One more time!", "Yeeaahh.." and "Comeon-a!" are found on GEW12 keybards (that you can easily find for 25$), so there is nothing special or "rare" about DJX.

Supports 8bit linear, compessed LDPCM and 10bit or 12bit as well - probably something else as well. Chip is 3.3V, but rom data inputs are fully 5v-tolerant (likely other inpus as well) and chip is used with 5V roms.

And sampling in both DJX and DJX-2 are done by the control processor
(simple cpu, not DSP!), using analog inputs designed for potentiometer slow readout. Scary lo-fi cheapness.
PSR-225, PSR-270, ?PSR-272, PSR-D1 (DJX)
HG73C205FD
(XU947B00)
SWX000
"Tone Generator"
RM1x, CVP-103, CVP-201
HG73C205AFD
(XU947C00)
SWX00B
"Tone Generator & CPU"
Has a great, expressive sound, and can sound rather delicate. Can operate as both a system controller and a real DSP. Usually used in pairs, with one doing system control and additional DSP functions (more inserts or effects sections), while the other does all wave and main effect funtionality.

When used alone, it is a good XG synthesizer.

Surprisingly it's found also in a PSR-350 with the ridiculous "DJ!" button, and everything suggesting that keyboard has the lofi GEW12 instead.

In AN-200 and DX-200 it is used as a controller, AWM sounds and effects processing. FM is done on a separate PLG-DX module, and for AN - a separate PLG150-AN board.

It is also both controller and DSP in a EZ-TP trumpet and EZ-EG guitar.

Developed in 1998.
AN-200, CLP-950, CVP-105,  CVP-107, CVP-109, CVP-202, CVP-203, CVP-204, CVP-205, CVP-206, CVP-208, CVP-210, DB-51XG, DD-55, DJXII, DJXIIB, DGX-300, DGX-500, DX-200, EZ-30, EZ-J53, EZ-EG, EZ-TP, MIE-2XG, P-60, P-90, P-120, PF-1000, PSR-280, PSR-350, PSR-450, PSR-540,  PSR-550, PSR-640, PSR-1000, PSR-1100, PSR-A1000, PSR-GX76, QY-100, S-03, S-08,  YPP-100, YPP-200
LC9111A-310
(XG077A00)
LDO2

Gate array with glue logic, LED scanning, general purpose outputs, memory page (16kbyte) flipping management for HD6303 CPU, as well as chip select decoding.
PSR-47
LC9111A-321SS28
(XG276A00)
SS28
"SS28"
Glue logic gate array, that also provides memory space extension (16kbyte pages) for large ROM connection.
PSS-380, PSS-390
LC92018B-476
(XI045A00)
RI54
"RI54 Gate Array"
Gate array for sharing wave bus between many GEW-5.
PSR-6700
LC92018B-500
(XI616A00)
LD03


PSR-4000
M50734SP
(XB826001)

"Master CPU"
A rather specific microcontroller that has various inputs and outpus only for electone stuff like knee lever and such.
HS-8
M60011-0110P
(XB828001)
ADEC
"Address Decoder"
Address decoder gate array used to generate chipselects for various peripherals around cpu.
HS-8

(XB829001)
GFA
"GEW Format Adaptor"
For GEW1.
HS-5, HS-8
R8A02032BG
(X8810A00)
SWX02

Wave processor, that contains fast (128MHz internal, 64MHz bus, PLL'ed from 16MHz quartz) SH-2A CPU (32bit), equipped with JTAG.
DTX-Multi 12, DGX-630, DGX-640, MDP-30, MOX-6, MOX-8, PSR-S550, R01 (Modus digital piano), SB-168
R8A02042BG
(YC479A00)
SWX08

Curiously, the DSP part for some reason is not allways used, and instead functions only as a system controller along with SWP51L for the wave and effects job. So in regards to its sound, only MX-series and DGX-650 should be taken into account, since these are the only ones with effects DRAM or WaveROM pins used.
DGX-650, MX-49, MX-61, MX-88, PSR-S750, PSR-S950
TC14L010
(XM407A00)

"Gate Array"
Toshiba gate array, customized for multiport async serial stuff for midi and host, misc i/o, as well as address space decoding logic.
MU-80
TC14L010AF-1742
(XQ460C00)
SHI
"Gate Array" Contains a lot of glue logic such as address map decoding.
PSR-4000
TC17G005AN-0023
(XB809001)
MI1, MI-1 I/O
"M-Electone Interface"
Electone/clavinova stuff circa 1987. Toshiba gate array, customized for some serial I/O related to ram packs.
CVP-8, DSR-1000, EL-40, EL-60, Electone HE-5, HS-5 and HS-8
TC17G008AP-0011
(XB829001)
GFA
"GEW Format Adaptor"
For GEW1 wave outputs
Electone HE-5
TC17G008AN-0013
(XB811001)
RBUF
"Rhythm Buffer"
Gate array that "emulates" two of strange serial roms (YM2190x) using data from classic parallel 8-bit ROM, up to 256kbytes. ShrinkDIP-42.
PSR-80, PSR-90, PSR-6300, HS-8
TC170C120SF-003
(XQ036A00)
SWP00
"(AWM Tone Generator) Standard Wave Processor"
Custom gate array ASIC manufactured by toshiba. Iconic XG sound of 1995.

Yes, CS1X has nothing more than a simply generic early XG module.
CS-1X, DB-50XG, MU-50, P50-m, PSR-520, PSR-620, PSR-4000, QS-300, QY-700, SW-60XG
TC203C060AF-001
(XS724A00)
SWP00M
"(AWM Tone Generator) Standard Wave Processor"
3.3V version of SWP00, possibly with some other changes, but not necessarily.
Custom gate array ASIC manufactured by toshiba.

Lofi-ish DSP that has some appealing aspects to its muddy sound.
QY-70, PSR-530, PSR-630
TC203C760HF-001
(XR738A00)
SWP30
"AWM Tone Generator coped with MEG, Standard Wave Processor"
Very nice flagship-beyound-XG sound of around 1997-1999. MU-90, MU-90R, MU-100, MU-100R, PSR-730
TC203C760HF-002
(XS725A00)
SWP30B
"AWM Tone Generator coped with MEG, Standard Wave Processor"
Some MU-100(R) have these ones instead of SWP30, so they are likely interchangeable/pin compatible.

Developed in 1996. Very nice flagship-beyound-XG sound of around 1997-1999.
A-5000, A-6000, CS-2X, CS-6R, CS-6X, CVP-207, CLP-208, CLP-209, CVP-210, CVP-700, CVP-900, EX-5, EX-5R, EX-7, Motif 6/7/8, MU-128, PSR-740, PSR-2000, PSR-2100, PSR-9000, RS-7000, S-30, S-80, S-90, SW-1000XG
T6TJ3XBG-0001
(X8940A00)
SWP51L
"Tone Generator"
A cut-down version of SWP51/B. Using full monstrous SWP51 in usual PSR kind of keyboards was obviously an overkill, so later ones use these smaller cut-down "Lite" ones.

MOX already was designed as MOXF, yet just had the second SWP51L not soldered/mounted on board, and a different/simplified firmware.
CVP-501, CVP-609, MOX-6, MOX-8,  MOXF-6, MOXF-8, PSR-S710, PSR-S910, PSR-S750, PSR-S950, R01 (Modus digital piano), Tyros-4
T6TZ2XBG-0001
(X7376A00)
SWP51
"Tone Generator"

CVP-401, Motif-XS, Motif-XF
T6TZ2XBG-0002
(X7376B00)
SWP51B
"Tone Generator" Quite a remarkable chip. For a yamaha, It's powerful and massive in all regards, rather comparable to Roland's amazing WX chip.
F-11 (Modus), H-11, Motif-XS Rack, PSR-S700, PSR-S900, Tyros-3
T8F02TB-0102
(X0060A00)
SWP50
"Tone Generator" Astounding DSP that can sound way different from all the legacy without much effort. It is powerful and rather comparable to Roland's amazing XV or even WX chip. CLP-150, CP-300, DDK-7, MO-6, MO-8, Motif Rack, Motif-ES, P-250, PF-500, PSR-1500, PSR-3000, S-90ES, Tyros, Tyros-2

iG custom ASICs

IC name
Yamaha's alias
Yamahas official short description My notes
Used in
iG02600
(pinout)
VCA
"Voltage Controlled Amplifier"
iG02600 - "Gain rank M"
iG02601 - "Gain rank L"
iG02602 - "Gain rank K"
FS-50, FS-70, FS-300, FS-500, C-55N
iG02610,
iG02611
VCF

Analog VCF.
C-55N
iG03290

"BBD Clock Driver"

C-55N, FS-50, FS-70, FS-300, FS-500
iG03971

"Reverb"

FS-50, FS-70, FS-300, FS-500
iG06110
IEF

Magnetic head amplifier for Playcard reader and additional filter for some implementations of playcard system as a filter for harmony obbligato voice filtering.
PC-100
iG06450
(pinout)
DRM1


FS-50, FS-70, FS-300, FS-500
iG06500
(pinout)
DAC
"Degital to Anlog Converter"

FS-50, FS-70, FS-300, FS-500, FX-10, FX-20
iG065300 GEF
"Low Pass Filter"

PC-100
iG07110
DRM2


FS-50, FS-70, FS-300, FS-500
iG071400 (internal schematic with pinout) MMA


PC-100
iG07950

"Clock Buffer"

FS-50, FS-70, FS-300, FS-500
iG09510
iG095100
GE6
"Generator"
Some interesting PCM wavetable synthesizer just for monophonic "solo" section, although it actually is 3-voice. Supports 8kbyte WaveROM. Requires external DAC.
PS-55, CN-1000
iG09520
iG095200
IE2
"Intelligence Electone"
Intelligence is allways watching you. And your playcards too. Seems to be more advanced version of YM1020.
CN-1000
iG09560
iG095600
(schematic with pinout)
DAC
"Digital Analog Converter"
Parallel input, "floating point" data: 10 bit mantissa and 3bit exponent. Two stock chips combined in one package: MN6007 and MN6008
CN-1000, PS-25, PS-35, PS-55
iG10771
(shrinkDIP-64)
GE7
"Tone Generator 7"
Interesting pre-FM soundsource, with sweet noisedrums and nice polyphony.
Massive 64-pin shrinkDIP. A bunch of pins are used for parallel DAC stuff, which is done on two resistor ladders (decoded 3-bits for exponent and 10-bit mantissa). Sadly it all gets mixed to one output (no separate ones for rhythm or something), so unless digital data gets captured and converted on our own board (and there is no frame/group sync, btw), everything is just a single channel. Contains comparator for battery-low checking, programmable metronome led driving, tempo pot ADC and timer for tempo IRQ generator, internal key frequency lookup table, and a single-loop wavetable ROM of sorts. Envelope and waveform is also set by just a preset variation (in chip registers) instead of true ADSR. By the way, PSR-40 is running on Z80 cpu typical system with no other custom chips than this one, so let's get on disassembling its firmware, as there is a lot to improve there. I've already disassembled it a bit, and figured out and commented some stuff, so a separate article for it is probably coming someday.
MK-100, PSS-260, PSS-450, PSR-40
iG10090
iG100900

"BBD Modulator"
Interesting BBD delay line chorus clock generator. Despite simple looks, contain two sine lookup ROMs and two DACs, besides a VCO, dac output switches and clock dividers.
I'll probably kludge up some tiny detailed article about it, but here's in short: ROMs are two pieces of 16x 4bit, containing a quarter period of sinewave, so that contents effectively fold out into 64 steps of 5bit wave. Clock inpuot gets divided by 19 and it is then used for first sinewave rom lookup counter, then divided by 16 and for the second. Using the switches, output wave can then be an externally mixed sine - slow ("chorus"), fast (rotary speaker "tremolo") or both. VCO provides clock for BBD, typically: 38kHz @1.6Vctl, 58kHz @2.5Vctl, 125kHz @3.4Vctl.
CN-1000, MK-100, PS-35, PS-55, PSR-60
iG06110
IEF
Quite possibly "Intelligence Electone Frontend"
Chip for playcard system, that interfaces the magnetic head to the YM1020
PC-100
iG06440




iG0606


Power amplifier, LA4142 clone

iG00153
VCO III


CS-30
iG00156
VCF


CS-30
iG12032
also YA3256


MaskROM with program for i8085 cpu. Contains pattern, lin-log and preset instrument data as well. No waveforms.
MK-100
iG15504




iG15601




iG156010
MIX-3
"Mixer 3"
Digital mixer
Electone HE-5

Thanks also to the guys who contributed or sent in some info I missed: Christoph Kukulies, Claus, Toralf Lenz, And Now It Is Dark and many more!

Thanks again and sorry if I haven't yet replied to some of you, I just have so many emails, it takes months to dig through!