Once the library has been initialized all of the library functions can be used, but at this point no data has been prepared yet. Here we make the preparations in order to make each data set usable in sequence.

First we DMA transfer the data from ROM that needs to be placed in RAM. The function used to secure a memory area in RAM from the audio heap is nuAuStlHeapAlloc.

Reserve memory from the audio heap

Function name:	nuAuStlHeapAlloc
Syntax:	void *nuAuStlHeapAlloc(s32 length)
Arguments:	length The size of memory secured from the heap
Return value:	Pointer to the reserved heap memory

Next we use nuPiReadRom to transfer the data to the reserved area.

Load data from ROM

Function name:	nuPiReadRom
Syntax:	void nuPiReadRom(u32 rom_addr, void* buf_ptr, u32 size)
Arguments:	rom_addr  Transfer origin(from) ROM address buf_ptr Pointer to transfer destination(to) buffer size Transfer size
Return value:	None

(*)Be sure that the size is an even number of bytes.

There are also two functions that can be used to find out the present state of the heap

Return the previously used sizes with audio heap

Function name:	nuAuStlGetHeapUsed
Syntax:	s32 nuAuStlGetHeapUsed(void)
Arguments:	None
Return value:	Size of audio heap being used

Return sizes with audio heap still available

Function name:	nuAuStlGetHeapFree
Syntax:	s32 nuAuStlGetHeapFree(void)
Arguments:	None
Return value:	Size of audio heap remaining

Next, we perform the necessary initialization of the Sound Effect Bank and Sample Bank from among the data to be used for audio playback. The first items initialized automatically become the default banks. For songs, all you have to do is place the data in RAM, and no initialization is necessary.

Initialize Sound Effect Bank

Function name:	MusFxBankInitialize
Syntax:	void MusFxBankInitialize(void *fxbank)
Arguments:	fxbank	Address of sound effect bank in RAM
Return value:	None

Initialize a sample bank

Function name:	MusPtrBankInitialize
Syntax:	void MusPtrBankInitialize(void *pbank, void *wbank)
Arguments:	pbank  Address of Sample Pointer Bank in RAM wbank Address of Sample Wave Bank in ROM
Return value:	None