tpak.c File Reference

Transfer Pak interface. More...

Macros
#define	TPAK_BLOCK_SIZE   0x20
	Transfer Pak command block size (32 bytes)
#define	TPAK_BANK_SIZE   0x4000
	Transfer Pak cartridge bank size (16 KiB)
Transfer Pak power control values
See also tpak_set_power
#define	TPAK_POWER_ON   0x84
	Transfer Pak power on.
#define	TPAK_POWER_OFF   0xFE
	Transfer Pak power off.
Transfer Pak address values
#define	TPAK_ADDRESS_POWER   0x8000
	Transfer Pak address for power control.
#define	TPAK_ADDRESS_BANK   0xA000
	Transfer Pak address for bank switching.
#define	TPAK_ADDRESS_STATUS   0xB000
	Transfer Pak address for status flags.
#define	TPAK_ADDRESS_DATA   0xC000
	Transfer Pak address for cartridge data.

Functions
int	tpak_set_value (int controller, uint16_t address, uint8_t value)
	Set Transfer Pak or Game Boy cartridge status/control value.
int	tpak_init (int controller)
	Prepare a Transfer Pak for read/write commands.
int	tpak_set_access (int controller, bool access_state)
	Set the access mode flag for a Transfer Pak.
int	tpak_set_power (int controller, bool power_state)
	Set the power enabled flag for a Transfer Pak.
int	tpak_set_bank (int controller, int bank)
	Set the cartridge data address memory bank for a Transfer Pak.
uint8_t	tpak_get_status (int controller)
	Get the status flags for a Transfer Pak.
int	tpak_get_cartridge_header (int controller, struct gameboy_cartridge_header *header)
	Read the Game Boy cartridge ROM header from a Transfer Pak.
int	tpak_write (int controller, uint16_t address, uint8_t *data, uint16_t size)
	Write data from a buffer to a Game Boy cartridge via Transfer Pak.
int	tpak_read (int controller, uint16_t address, uint8_t *buffer, uint16_t size)
	Read data from a Game Boy cartridge to a buffer via Transfer Pak.
bool	tpak_check_header (struct gameboy_cartridge_header *header)
	Verify a Game Boy cartridge ROM header checksum.

Detailed Description

Transfer Pak interface.

Function Documentation

tpak_set_value()

int tpak_set_value	(	int	controller,
		uint16_t	address,
		uint8_t	value
	)

Set Transfer Pak or Game Boy cartridge status/control value.

This is an internal helper to set a Transfer Pak status or control setting. This function is not suitable for setting individual bytes in Save RAM!

Parameters

[in]	controller	The controller (0-3) with Transfer Pak connected.
[in]	address	Address of the setting. Should be between 0x8000 and 0xBFE0
[in]	value	A byte of data to fill the write buffer with.

tpak_init()

int tpak_init

(

int

controller

)

Prepare a Transfer Pak for read/write commands.

Powers on the Transfer Pak and enables access to the Game Boy cartridge. Also performs status checks to confirm the Transfer Pak can be accessed reliably.

Parameters

[in]

controller

The controller (0-3) with Transfer Pak connected.

Returns

0 if successful or TPAK_ERROR otherwise.

tpak_set_access()

int tpak_set_access	(	int	controller,
		bool	access_state
	)

Set the access mode flag for a Transfer Pak.

Parameters

[in]	controller	The controller (0-3) with Transfer Pak connected.
[in]	access_state	Whether to allow access to the Game Boy cartridge.

Returns

0 if successful or TPAK_ERROR otherwise.

tpak_set_power()

int tpak_set_power	(	int	controller,
		bool	power_state
	)

Set the power enabled flag for a Transfer Pak.

Parameters

[in]	controller	The controller (0-3) with Transfer Pak connected.
[in]	power_state	True to power the Transfer Pak and cartridge on, false to turn it off.

Returns

0 if successful or TPAK_ERROR otherwise.

tpak_set_bank()

int tpak_set_bank	(	int	controller,
		int	bank
	)

Set the cartridge data address memory bank for a Transfer Pak.

Change the bank of address space that is available for tpak_read and tpak_write between Transfer Pak addresses 0xC000 and 0xFFFF.

Parameters

[in]	controller	The controller (0-3) with Transfer Pak connected.
[in]	bank	The bank (0-3) to switch to.

Returns

0 if successful or TPAK_ERROR otherwise.

tpak_get_status()

uint8_t tpak_get_status

(

int

controller

)

Get the status flags for a Transfer Pak.

Parameters

[in]

controller

The controller (0-3) with Transfer Pak connected.

Returns

The status byte with TPAK_STATUS flags

tpak_get_cartridge_header()

int tpak_get_cartridge_header	(	int	controller,
		struct gameboy_cartridge_header *	header
	)

Read the Game Boy cartridge ROM header from a Transfer Pak.

Parameters

[in]	controller	The controller (0-3) with Transfer Pak connected.
[out]	header	Pointer to destination Game Boy cartridge ROM header data structure.

Returns

0 if successful or TPAK_ERROR otherwise.

tpak_write()

int tpak_write	(	int	controller,
		uint16_t	address,
		uint8_t *	data,
		uint16_t	size
	)

Write data from a buffer to a Game Boy cartridge via Transfer Pak.

Save RAM is located between gameboy addresses 0xA000 and 0xBFFF, which is in the Transfer Pak's bank 2. This function does not account for cartridge bank switching, so to switch between MBC1 RAM banks, for example, you'll need to switch to Tpak bank 1, and write to address 0xE000, which translates to address 0x6000 on the gameboy.

Parameters

[in]	controller	The controller (0-3) with Transfer Pak connected.
[in]	address	address in Game Boy cartridge space to write to.
[in]	data	buffer containing the data to write.
[in]	size	length of the buffer.

Returns

0 if successful or TPAK_ERROR otherwise.

tpak_read()

int tpak_read	(	int	controller,
		uint16_t	address,
		uint8_t *	buffer,
		uint16_t	size
	)

Read data from a Game Boy cartridge to a buffer via Transfer Pak.

Parameters

[in]	controller	The controller (0-3) with Transfer Pak connected.
[in]	address	address in Game Boy cartridge space to read from.
[in]	buffer	buffer to copy cartridge data into.
[in]	size	length of the data to be read.

Returns

0 if successful or TPAK_ERROR otherwise.

tpak_check_header()

bool tpak_check_header

(

struct gameboy_cartridge_header *

header

)

Verify a Game Boy cartridge ROM header checksum.

Confirms that the Transfer Pak is connected and working properly.

Parameters

[in]

header

The Game Boy ROM header to check.