Device Access

MIE board identification, EEPROM, and firmware init More...

Functions
char *	mie_get_id (char *dst)
	Read the MIE board identifier string.
bool	mie_get_eeprom (void *dst)
	Read the MIE on-board EEPROM.
bool	mie_set_eeprom (uint8_t *eeprom)
	Write the MIE on-board EEPROM.
uint16_t	mie_eeprom_crc16 (const uint8_t *buf, size_t size)
	Compute Sega NAOMI EEPROM CRC-16.
void	mie_eeprom_fix_crc (uint8_t *eeprom)
	Recompute NAOMI EEPROM CRC fields in a 128-byte buffer.
bool	mie_init_fw (const char *fw_path)
	Initialize MIE/JVS, uploading Z80 firmware when needed.

Detailed Description

MIE board identification, EEPROM, and firmware init

Function Documentation

mie_eeprom_crc16()

uint16_t mie_eeprom_crc16	(	const uint8_t *	buf,
		size_t	size )

Compute Sega NAOMI EEPROM CRC-16.

CRC-16-CCITT variant with seed 0xDEBDEB00 and an extra round over a trailing 0x00 byte. Used by MIE EEPROM and NAOMI backup SRAM bookkeeping blocks.

Parameters

buf	Data to checksum.
size	Length in bytes.

Returns

CRC-16 value.

See also

mie_eeprom_fix_crc

mie_eeprom_fix_crc()

void mie_eeprom_fix_crc

(

uint8_t *

eeprom

)

Recompute NAOMI EEPROM CRC fields in a 128-byte buffer.

Updates the duplicated CRC16 headers for the system-settings block (bytes 0–17) and the game-settings block (bytes 36–43).

Parameters

eeprom

Buffer to update (MIE_EEPROM_SIZE bytes).

See also

mie_eeprom_crc16, mie_get_eeprom, mie_set_eeprom

mie_get_eeprom()

bool mie_get_eeprom

(

void *

dst

)

Read the MIE on-board EEPROM.

Performs a synchronous EEPROM fetch over the MIE IO protocol.

Parameters

dst	Destination buffer (MIE_EEPROM_SIZE bytes).

Return values

true	Read succeeded.
false	Invalid buffer or I/O failed.

See also

MIE_EEPROM_SIZE, mie_set_eeprom

mie_get_id()

char * mie_get_id

(

char *

dst

)

Read the MIE board identifier string.

Sends the MIE GET ID command and copies the response into dst.

Parameters

dst	Destination buffer (MIE_ID_SIZE bytes).

Returns

dst on success, NULL on failure.

See also

MIE_ID_SIZE

mie_init_fw()

bool mie_init_fw

(

const char *

fw_path

)

Initialize MIE/JVS, uploading Z80 firmware when needed.

Registers the driver if needed, probes whether the Z80 bridge is already active (for example after the original NAOMI BIOS or DreamShell), and uploads fw_path when JVS communication is not yet available.

Intended for early boot on NAOMI hardware before the normal Maple scan completes JVS setup. Returns false on retail Dreamcast.

Parameters

fw_path

Path to mie_z80.bin firmware image.

Return values

true	Z80/JVS initialization succeeded.
false	Invalid path, not NAOMI hardware, or init failed.

See also

mie_init_scan

mie_set_eeprom()

bool mie_set_eeprom

(

uint8_t *

eeprom

)

Write the MIE on-board EEPROM.

Performs a synchronous EEPROM write over the MIE IO protocol. Data is written in 16-byte chunks with pacing between transfers.

Parameters

eeprom

Source buffer (MIE_EEPROM_SIZE bytes).

Return values

true	Write succeeded.
false	Invalid buffer or I/O failed.

See also

MIE_EEPROM_SIZE, mie_get_eeprom