furnace/doc/4-instrument/ay8910.md

AY-3-8910 instrument editor

the AY-3-8910 instrument editor consists of three tabs.

Sample

for sample settings, see the Sample instrument editor.

the only differences are the lack of an "Use wavetable" option, and the presence of a "Use sample" one.

note that using samples on AY is CPU expensive!

Timer Macros

• Timer FX: timer effect type sequence. 0- off, 1- tone PWM, 2- envelope distortion, 3- reserved
• TFX Offset: PWM speed sequence.
• Timer Num and Den: multiplier of a virtual square wave modulator (?)
• PWM Boundary: sets the range of a pulse width modulation

note that timer effects might not be supported by VGM players, and are rather CPU expensive!

Macros

• Volume: volume sequence.
• Arpeggio: pitch sequence.
• Noise Freq: noise generator frequency sequence.
  • note: global!
• Waveform: selector of sound type - square wave tone, noise and/or envelope generator.
  • you may select more than one option.
• Pitch: fine pitch.
• Phase Reset: trigger restart of envelope.
• Envelope: configures the hardware envelope.
  • enable: sets whether envelope is enabled.
  • direction: flips the envelope's direction.
  • alternate: when enabled, the envelope will change direction once it hits a boundary.
  • hold: sets whether the envelope should stop when hitting boundary, or loop.
• AutoEnv Num: sets the envelope to the channel's frequency multiplied by numerator.
• AutoEnv Den: sets the envelope to the channel's frequency multiplied by denominator.
  • these two must be set in order for AutoEnv to work!