Macronix DSP

Macronix DSP is a 16 bit programmable DSP coprocessor in the Nintendo GameCube\Wii\Wii U, manufactured by Macronix. It has its own ADPCM hardware decoder to offload the DSP. It stores PCM\ADPCM data in the 16 MB of ARAM, and can store extra data such as textures and animations.

Macronix DSP microcode is written in assembly. asnd & aesnd is the homebrew DSP microcode that exists in Devkitpro, it mixes up to 64 channels @ 48000hz.

JAudio(JSystem) DSP microcode also seems to contain these types:

SRC_SQUARE_WAVE
SQUARE_WAVE_25PCT
SAW_WAVE
PCM8
PCM16
DSP-ADPCM

DSP Specs

 Clock: 81MHz(GC) or 121.5MHz(Wii)
 Bits: 16bit
 Endian: Big
 Data RAM: 8KB
 Data ROM: 4KB
 Instruction RAM: 8KB
 Instruction ROM: 8KB (Macronix, Nintendo)
 Hardware Decoder: DSP-ADPCM

DSP Programs

 Bootrom IPL microcode x2 (Macronix, Nintendo)
 DSP ARAM/Init microcode
 Memory Card microcode - handles memory card security & unlocking
 Audio System(AX) microcode - mixing, filters, Dolby logic pro II, effects done on CPU
 JAudio(JSystem) microcode - mixing, filters, Dolby logic pro II, effects, channels, GBA decryption in some games
 GBA Multiboot microcode - decrypts GBA multiboot program

Homebrew DSP Programs

 ASnd microcode - mixing
 AESnd microcode - mixing