979 bytes added
, 20:46, 28 March 2010
The DSi has extended the sound memory mapped I/O interface.
=== ARM7 IO REGISTERS ===
{| class="wikitable" border="1"
|-
! ADDRESS
! WIDTH (bytes)
! NAME
|-
| 0x04004700
| 2
| REG_SNDEXCNT
|}
{| class="wikitable" border="1"
|+ '''REG_SNDEXCNT'''
|-
! BIT
! DESCRIPTION
|-
| 3-0
| NITRO/DSP ratio, valid range is 0 to 8.
|-
| 13
| I2S frequency
|-
| 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:
{| class="wikitable" border="1"
|-
! Setting
! Description
|-
| 0
| NITRO sound 8/8, DSP 0/8 (=NITRO sound only)
|-
| 1
| NITRO sound 7/8, DSP 1/8
|-
| 2
| NITRO sound 6/8, DSP 2/8
|-
| 3
| NITRO sound 5/8, DSP 3/8
|-
| 4
| NITRO sound 4/8, DSP 4/8
|-
| 5
| NITRO sound 3/8, DSP 5/8
|-
| 6
| NITRO sound 2/8, DSP 6/8
|-
| 7
| NITRO sound 1/8, DSP 7/8
|-
| 8
| NITRO sound 0/8, DSP 8/8 (=DSP sound only)
|}