2 Pulse channels:
- 8 level pulse duty cycle, DAC mode(just ignores duty cycle)/pulse wave mode, 4 bit volume.
- Furnace support PCM playback in pulse channels with duty cycle ignore mode.
Sawtooth:
- nothing but 6 bit volume (8 bit accumulator in technically) and 12 bit frequency (periodic).
VRC6 instrument:
- 6 bit Volume macro for finer sawtooth volume handling, also 3 bit Duty cycle macro for pulse channels.
Duty, PCM mode command and Duty macro affects for pulse channel only.
