Specifications

4-16 Mixer Chip Programming
Registers 0x38/0x39 (Line volume .L/.R)
Register 0x3A (Mic volume)
5 bits per channel, giving 32 levels.
0 to 31 ⇒ – 62 dB to 0 dB, in 2 dB steps.
Default is 0 ⇒ – 62 dB.
Register 0x3B (PC Speaker volume)
2 bits, giving 4 levels.
0 to 3 ⇒ – 18 dB to 0 dB, in 6 dB steps.
Default is 0 ⇒ – 18 dB.
Register 0x3C (Output mixer switches)
Set the appropriate bit to 1 to close the switch, 0 to open.
The default is
Line.L Line.R CD.L CD.R Mic
11111
Register 0x3D (Input Mixer.L switches)
Set the appropriate bit to 1 to close the switch, 0 to open.
The default is
MIDI.L MIDI.R Line.L Line.R CD.L CD.R Mic
0010101
Register 0x3E (Input Mixer.R switches)
Set the appropriate bit to 1 to close the switch, 0 to open.
The default is
MIDI.L MIDI.R Line.L Line.R CD.L CD.R Mic
0001011
When recording in mono, note that samples will only be taken from
the left input mixer.
So, if a mono recording of a stereo source is desired, the switches
controlled by registers
0x3D
and
0x3E
must be manipulated to
enable both channels of a stereo source to be mixed together first
into the left input mixer before being sampled.