HEL Library: BIOS Functions

The BIOS Functions Module can be used to execute functions from the GBA's BIOS. Several functions expect halfword or word-aligned memory addresses to work properly.

The debug library contains a memory address-checking-mechanism which will display an error when an incoming parameter contains an invalid memory address. Invalid in sense of wrong alignment.

Function Documentation

void ATTR_NOINLINE ATTR_NOINSTRUMENT hel_SwiCpuFastCopy	(	void *	pDst,
		const void *	pSrc,
		u32	LengthInWords
	)

Copy a block of memory.

Parameters:

`[in]`	pDst	Pointer to copy destination (must be word aligned).
`[in]`	pSrc	Pointer to block to copy (must be word aligned).
`[in]`	LengthInWords	Length in 32bit words of block to copy. This value must be multiple of 8, which means you can only copy blocks of memory which are multiple 32bytes.

    // copy 256 bytes from pSrc to pDest
    hel_SwiCpuFastCopy(pDst, pSrc, 256/sizeof(u32));

void ATTR_NOINLINE ATTR_NOINSTRUMENT hel_SwiHalt ( void )

Switch CPU into low-power mode.

hel_SwiHalt switch the CPU into low-power mode. The Halt mode is terminated when any interrupt becomes executed.

void hel_SwiLZ77UnCompVram	(	void *	pDst,
		const void *	pSrc
	)

Expand LZ77-compressed data.

Parameters:

`[in]`	pDst	Destination address, must be halfword aligned!
`[in]`	pSrc	Source address, must be word aligned and data size must be multiple 4.

void hel_SwiLZ77UnCompWram	(	void *	pDst,
		const void *	pSrc
	)

Expand LZ77-compressed data.

Parameters:

`[in]`	pDst	Destination address.
`[in]`	pSrc	Source address, must be word aligned and data size must be multiple 4.

void hel_SwiRLUnCompVram	(	void *	pDst,
		const void *	pSrc
	)

Expand Run-Length-Encoded data.

Parameters:

`[in]`	pDst	Destination address, must be halfword aligned!
`[in]`	pSrc	Source address, must be word aligned and data size must be multiple 4.

void hel_SwiRLUnCompWram	(	void *	pDst,
		const void *	pSrc
	)

Expand Run-Length-Encoded data.

Parameters:

`[in]`	pDst	Destination address.
`[in]`	pSrc	Source address, must be word aligned and data size must be multiple 4.

void ATTR_NOINLINE ATTR_NOINSTRUMENT hel_SwiSoftReset ( u32 ReturnAddr )

Reset device.

hel_SwiSoftReset clears the CPU internal RAM area from 3007E00h-3007FFFh, initializes system, supervisor, and irq stack pointers, and sets R0-R12 to zero, and enters system mode.

Parameters:

[in] ReturnAddr Return address selection (0 for 0x8000000, 1-255 for 0x2000000)

Note:: Description copied from GBATek.

void hel_SwiUnComp	(	void *	pDst,
		const void *	pSrc,
		u32	CompressionType
	)

Expand compressed data.

Parameters:

`[in]`	pDst	Destination address
`[in]`	pSrc	Source address
`[in]`	CompressionType	Compression-type of source data. This can be one of the following predefines values: `COMPRESSION_TYPE_LZ77VRAM` `COMPRESSION_TYPE_LZ77WRAM` `COMPRESSION_TYPE_RLEVRAM` `COMPRESSION_TYPE_RLEWRAM`

Note:: The destination and source addresses have to be aligned. Please see corresponding decompress function such as hel_SwiLZ77UnCompVram, hel_SwiLZ77UnCompWram, hel_SwiRLUnCompVram, hel_SwiRLUnCompWram

void ATTR_NOINLINE ATTR_NOINSTRUMENT hel_SwiVBlankIntrWait ( void )

Wait for Vertical Blank interrupt.

The hel_SwiVBlankIntrWait function calls SWI 5, which continues to wait in Halt status until a new Vertical Blank interrupt occurs.

Note:: The VBL Interrupt-Handler must call hel_IntrAcknowledge.

BIOS Functions

Functions

Detailed Description

Function Documentation