mirror of
https://github.com/tildearrow/furnace.git
synced 2024-11-06 12:55:05 +00:00
70 lines
2.5 KiB
Markdown
70 lines
2.5 KiB
Markdown
# Yamaha YM2151
|
|
|
|
the sound chip powering several arcade boards, the Sharp X1/X68000 and the Commander X16. 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.
|
|
|
|
in most arcade boards the chip was used in combination with a PCM chip, like [SegaPCM](segapcm.md) or [OKI's line of ADPCM chips](oki.md).
|
|
|
|
# effects
|
|
|
|
- `10xx`: set noise frequency of channel 8 operator 4. 00 disables noise while 01 to 20 enables it.
|
|
- `11xx`: set feedback of channel.
|
|
- `12xx`: set operator 1 level.
|
|
- `13xx`: set operator 2 level.
|
|
- `14xx`: set operator 3 level.
|
|
- `15xx`: set operator 4 level.
|
|
- `16xy`: set multiplier of operator.
|
|
- `x` is the operator (1-4).
|
|
- `y` is the multiplier.
|
|
- `17xx`: set LFO speed.
|
|
- `18xx`: set LFO waveform. `xx` may be one of the following:
|
|
- `00`: saw
|
|
- `01`: square
|
|
- `02`: triangle
|
|
- `03`: noise
|
|
- `19xx`: set attack of all operators.
|
|
- `1Axx`: set attack of operator 1.
|
|
- `1Bxx`: set attack of operator 2.
|
|
- `1Cxx`: set attack of operator 3.
|
|
- `1Dxx`: set attack of operator 4.
|
|
- `1Exx`: set LFO AM depth.
|
|
- `1Fxx`: set LFO PM depth.
|
|
- `30xx`: enable envelope hard reset.
|
|
- this works by inserting a quick release and tiny delay before a new note.
|
|
- `50xy`: set AM of operator.
|
|
- `x` is the operator (1-4). a value of 0 means "all operators".
|
|
- `y` determines whether AM is on.
|
|
- `51xy` set SL of operator.
|
|
- `x` is the operator (1-4). a value of 0 means "all operators".
|
|
- `y` is the value.
|
|
- `52xy` set RR of operator.
|
|
- `x` is the operator (1-4). a value of 0 means "all operators".
|
|
- `y` is the value.
|
|
- `53xy` set DT of operator.
|
|
- `x` is the operator (1-4). a value of 0 means "all operators".
|
|
- `y` is the value:
|
|
- 0: +0
|
|
- 1: +1
|
|
- 2: +2
|
|
- 3: +3
|
|
- 4: -0
|
|
- 5: -3
|
|
- 6: -2
|
|
- 7: -1
|
|
- `54xy` set RS of operator.
|
|
- `x` is the operator (1-4). a value of 0 means "all operators".
|
|
- `y` is the value.
|
|
- `55xy` set DT2 of operator.
|
|
- `x` is the operator (1-4). a value of 0 means "all operators".
|
|
- `y` is the value.
|
|
- `56xx`: set DR of all operators.
|
|
- `57xx`: set DR of operator 1.
|
|
- `58xx`: set DR of operator 2.
|
|
- `59xx`: set DR of operator 3.
|
|
- `5Axx`: set DR of operator 4.
|
|
- `5Bxx`: set D2R/SR of all operators.
|
|
- `5Cxx`: set D2R/SR of operator 1.
|
|
- `5Dxx`: set D2R/SR of operator 2.
|
|
- `5Exx`: set D2R/SR of operator 3.
|
|
- `5Fxx`: set D2R/SR of operator 4.
|