59 lines
1.9 KiB
Markdown
59 lines
1.9 KiB
Markdown
# Taito Arcade/Yamaha YM2610B
|
|
|
|
YM2610B is basically YM2610 with 2 extra FM channels used at some 90s Taito arcade hardware.
|
|
it is backward compatible with the original chip.
|
|
|
|
# effects
|
|
|
|
- `10xy`: set LFO parameters.
|
|
- `x` toggles the LFO.
|
|
- `y` sets its speed.
|
|
- `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 mutliplier.
|
|
- `18xx`: toggle extended channel 2 mode.
|
|
- 0 disables it and 1 enables it.
|
|
- only in extended channel 2 system.
|
|
- `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.
|
|
- `20xx`: set SSG channel mode. `xx` may be one of the following:
|
|
- `00`: square
|
|
- `01`: noise
|
|
- `02`: square and noise
|
|
- `03`: nothing (apparently)
|
|
- `04`: envelope and square
|
|
- `05`: envelope and noise
|
|
- `06`: envelope and square and noise
|
|
- `07`: nothing
|
|
- `21xx`: set noise frequency. `xx` is a value between 00 and 1F.
|
|
- `22xy`: set envelope mode.
|
|
- `x` sets the envelope shape, which may be one of the following:
|
|
- `0: \___` decay
|
|
- `4: /___` attack once
|
|
- `8: \\\\` saw
|
|
- `9: \___` decay
|
|
- `A: \/\/` inverse obelisco
|
|
- `B: \¯¯¯` decay once
|
|
- `C: ////` inverse saw
|
|
- `D: /¯¯¯` attack
|
|
- `E: /\/\` obelisco
|
|
- `F: /___` attack once
|
|
- if `y` is 1 then the envelope will affect this channel.
|
|
- `23xx`: set envelope period low byte.
|
|
- `24xx`: set envelope period high byte.
|
|
- `25xx`: slide envelope period up.
|
|
- `26xx`: slide envelope period down.
|
|
- `29xy`: enable SSG auto-envelope mode.
|
|
- 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.
|