The DSi has extended the sound memory mapped I/O interface.
ARM7 IO REGISTERS
| ADDRESS
|
WIDTH (bytes)
|
NAME
|
| 0x04004700
|
2
|
REG_SNDEXCNT
|
REG_SNDEXCNT
| BIT
|
DESCRIPTION
|
| 3-0
|
NITRO/DSP ratio, valid range is 0 to 8.
|
| 13
|
I2S frequency, 0=32.73 kHz, 1=47.61 kHz
|
| 14
|
Mute status
|
NITRO/DSP ratio
The DSP can generate sound output aswell, alongside the old NITRO sound mixer. The following settings configure the ratio between DSP and NITRO mixer output:
| Setting
|
Description
|
| 0
|
DSP sound 8/8, NITRO sound 0/8 (=DSP sound only)
|
| 1
|
DSP sound 7/8, NITRO sound 1/8
|
| 2
|
DSP sound 6/8, NITRO sound 2/8
|
| 3
|
DSP sound 5/8, NITRO sound 3/8
|
| 4
|
DSP sound 4/8, NITRO sound 4/8
|
| 5
|
DSP sound 3/8, NITRO sound 5/8
|
| 6
|
DSP sound 2/8, NITRO sound 6/8
|
| 7
|
DSP sound 1/8, NITRO sound 7/8
|
| 8
|
DSP sound 0/8, NITRO sound 8/8 (=NITRO sound only)
|