Neo Geo/Yamaha YM2610

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

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.

2.1 KiB Raw Blame History

Neo Geo/Yamaha YM2610

effects

2.1 KiB

Raw Blame History