PSG registers.

Summary

PSG registers.
Registers.
psgport	PSG port.
psg_mainvol	Global sound volume.
psg_freq_lo	Fine frequency adjust.
psg_freq_hi	Rough frequency adjust.
psg_ctrl	Control register.
psg_pan	Channel balance.
psg_wavebuf	Channel sound data.
psg_noise	Noise control.
psg_lfofreq	LFO frequency.
psg_lfoctrl	LFO trigger and control.
Control Register Flags.
PSG_CTRL_CHAN_ON	PSG control register bit masks 1 - Channel on 0 - Channel off
PSG_CTRL_WRITE_RESET	Reset waveform write index to 0
PSG_CTRL_DDA_ON	DDA output.
PSG_CTRL_VOL_MASK	Channel volume.
PSG_CTRL_FULL_VOLUME	Channel maximum volume (bit 5 is unused)

Registers.

psgport

psgport = $0800

PSG port.

psg_mainvol

psg_mainvol = psgport+1

Global sound volume.

psg_freq_lo

psg_freq_lo = psgport+2

Fine frequency adjust.

psg_freq_hi

psg_freq_hi = psgport+3

Rough frequency adjust.

psg_ctrl

psg_ctrl = psgport+4

Control register.

psg_pan

psg_pan = psgport+5

Channel balance.

psg_wavebuf

psg_wavebuf = psgport+6

Channel sound data.

psg_noise

psg_noise = psgport+7

Noise control.

psg_lfofreq

psg_lfofreq = psgport+8

LFO frequency.

psg_lfoctrl

psg_lfoctrl = psgport+9

LFO trigger and control.

Control Register Flags.

PSG_CTRL_CHAN_ON

PSG_CTRL_CHAN_ON = %10000000

PSG control register bit masks 1 - Channel on 0 - Channel off

PSG_CTRL_WRITE_RESET

PSG_CTRL_WRITE_RESET = %01000000

Reset waveform write index to 0

PSG_CTRL_DDA_ON

PSG_CTRL_DDA_ON = %11000000

DDA output. 1 - on 0 - off

PSG_CTRL_VOL_MASK

PSG_CTRL_VOL_MASK = %00011111

Channel volume.

PSG_CTRL_FULL_VOLUME

PSG_CTRL_FULL_VOLUME = %00111111

Channel maximum volume (bit 5 is unused)