EEPROM AT24Cxx Series

Low-level driver for the AT24CXX Series EEPROM controller.

This driver provides access to the main features of the AT24CXX Series EEPROM.

Macros
#define	at24c_build_word_address(p_u8, addr)

Functions
static void	at24cxx_acknowledge_polling (twi_package_t *twi_package)
	Poll the acknowledge from AT24CXX. More...
uint32_t	at24cxx_fill_pattern (uint32_t u32_start_address, uint32_t u32_end_address, uint8_t u8_pattern)
	Fill the specified pattern to AT24CXX. More...
uint32_t	at24cxx_read_byte (uint32_t u32_address, uint8_t *p_rd_byte)
	Read single byte from AT24CXX. More...
uint32_t	at24cxx_read_continuous (uint32_t u32_start_address, uint16_t u16_length, uint8_t *p_rd_buffer)
	Read multiple bytes continuously from AT24CXX. More...
uint32_t	at24cxx_read_page (uint32_t u32_page_address, uint32_t u32_page_size, uint8_t *p_rd_buffer)
	Read data from the specified page in AT24CXX. More...
void	at24cxx_reset (void)
	Reset AT24CXX. More...
uint32_t	at24cxx_write_byte (uint32_t u32_address, uint8_t u8_value)
	Write single byte to AT24CXX. More...
uint32_t	at24cxx_write_continuous (uint32_t u32_start_address, uint16_t u16_length, uint8_t const *p_wr_buffer)
	Write multiple bytes continuously to AT24CXX. More...
uint32_t	at24cxx_write_page (uint32_t u32_page_address, uint32_t u32_page_size, uint8_t const *p_wr_buffer)
	Write data to the specified page in AT24CXX. More...

#define at24c_build_word_address	(		p_u8,
			addr
	)

Value:

do {\
        p_u8[0] = (uint8_t)(addr >> 8);\
        p_u8[1] = (uint8_t)(addr >> 0);\
    } while (0)

Referenced by at24cxx_read_byte(), at24cxx_read_continuous(), at24cxx_read_page(), at24cxx_write_byte(), at24cxx_write_continuous(), and at24cxx_write_page().

static void at24cxx_acknowledge_polling ( twi_package_t *  twi_package )

static

Poll the acknowledge from AT24CXX.

Parameters

twi_package

Pointer to TWI data package. Only the slave address is used in the acknowledge polling.

References twi_packet::addr, addr, twi_packet::addr_length, BOARD_AT24C_TWI_INSTANCE, buffer, twi_packet::buffer, data, twi_packet::length, twi_master_write(), and TWI_SUCCESS.

Referenced by at24cxx_write_byte(), at24cxx_write_continuous(), and at24cxx_write_page().

uint32_t at24cxx_fill_pattern	(	uint32_t	u32_start_address,
		uint32_t	u32_end_address,
		uint8_t	u8_pattern
	)

Fill the specified pattern to AT24CXX.

Parameters

u32_start_address	The first address to be filled.
u32_end_address	The last address to be filled.
u8_pattern	The pattern to be filled.

Returns

AT24C_WRITE_SUCCESS if the pattern was filled, AT24C_WRITE_FAIL otherwise.

References addr, AT24C_WRITE_FAIL, AT24C_WRITE_SUCCESS, and at24cxx_write_byte().

uint32_t at24cxx_read_byte	(	uint32_t	u32_address,
		uint8_t *	p_rd_byte
	)

Read single byte from AT24CXX.

Parameters

u32_address	Address of the byte to read.
p_rd_byte	Pointer to memory where the read byte will be stored.

Returns

AT24C_READ_SUCCESS if one byte was read, AT24C_READ_FAIL otherwise.

References twi_packet::addr, twi_packet::addr_length, at24c_build_word_address, AT24C_MEM_ADDR_LEN, AT24C_READ_FAIL, AT24C_READ_SUCCESS, BOARD_AT24C_ADDRESS, BOARD_AT24C_TWI_INSTANCE, twi_packet::buffer, twi_packet::chip, twi_packet::length, twi_master_read(), and TWI_SUCCESS.

uint32_t at24cxx_read_continuous	(	uint32_t	u32_start_address,
		uint16_t	u16_length,
		uint8_t *	p_rd_buffer
	)

Read multiple bytes continuously from AT24CXX.

Parameters

u32_start_address	Address of the first byte to read.
u16_length	Number of bytes to read.
p_rd_buffer	Pointer to memory where the read bytes will be stored.

Returns

AT24C_READ_SUCCESS if one byte was read, AT24C_READ_FAIL otherwise.

References twi_packet::addr, twi_packet::addr_length, at24c_build_word_address, AT24C_MEM_ADDR_LEN, AT24C_READ_FAIL, AT24C_READ_SUCCESS, BOARD_AT24C_ADDRESS, BOARD_AT24C_TWI_INSTANCE, twi_packet::buffer, twi_packet::chip, twi_packet::length, twi_master_read(), and TWI_SUCCESS.

uint32_t at24cxx_read_page	(	uint32_t	u32_page_address,
		uint32_t	u32_page_size,
		uint8_t *	p_rd_buffer
	)

Read data from the specified page in AT24CXX.

Parameters

u32_page_address	The page number.
u32_page_size	The size of the page (which varies with the chips).
p_rd_buffer	Pointer to array where the bytes read are to be stored.

Returns

AT24C_READ_SUCCESS if the page was read, AT24C_READ_FAIL otherwise.

References twi_packet::addr, twi_packet::addr_length, at24c_build_word_address, AT24C_MEM_ADDR_LEN, AT24C_READ_FAIL, AT24C_READ_SUCCESS, BOARD_AT24C_ADDRESS, BOARD_AT24C_TWI_INSTANCE, twi_packet::buffer, twi_packet::chip, twi_packet::length, twi_master_read(), and TWI_SUCCESS.

void at24cxx_reset

(

void

)

Reset AT24CXX.

Send 9 clock cycles to reset memory state.

Note

IO mode is used in this function, so it can be used even if TWI is not enabled.

References BOARD_CLK_TWI_EEPROM, BOARD_CLK_TWI_MUX_EEPROM, delay_us, IOPORT_DIR_OUTPUT, ioport_disable_pin(), ioport_enable_pin(), ioport_set_pin_dir(), ioport_set_pin_level(), and ioport_set_pin_mode().

uint32_t at24cxx_write_byte	(	uint32_t	u32_address,
		uint8_t	u8_value
	)

Write single byte to AT24CXX.

Parameters

u32_address	Address of the byte to write.
u8_value	Value that will be written to the specified address.

Returns

AT24C_WRITE_SUCCESS if single byte was written, AT24C_WRITE_FAIL otherwise.

References twi_packet::addr, twi_packet::addr_length, at24c_build_word_address, AT24C_MEM_ADDR_LEN, AT24C_WRITE_FAIL, AT24C_WRITE_SUCCESS, at24cxx_acknowledge_polling(), BOARD_AT24C_ADDRESS, BOARD_AT24C_TWI_INSTANCE, twi_packet::buffer, twi_packet::chip, twi_packet::length, twi_master_write(), and TWI_SUCCESS.

Referenced by at24cxx_fill_pattern().

uint32_t at24cxx_write_continuous	(	uint32_t	u32_start_address,
		uint16_t	u16_length,
		uint8_t const *	p_wr_buffer
	)

Write multiple bytes continuously to AT24CXX.

Parameters

u32_start_address	Address of the first byte in transaction.
u16_length	Number of bytes to write.
p_wr_buffer	Pointer to array where the bytes to be written are stored.

Returns

AT24C_WRITE_SUCCESS if single byte was written, AT24C_WRITE_FAIL otherwise.

References twi_packet::addr, twi_packet::addr_length, at24c_build_word_address, AT24C_MEM_ADDR_LEN, AT24C_WRITE_FAIL, AT24C_WRITE_SUCCESS, at24cxx_acknowledge_polling(), BOARD_AT24C_ADDRESS, BOARD_AT24C_TWI_INSTANCE, twi_packet::buffer, twi_packet::chip, twi_packet::length, twi_master_write(), and TWI_SUCCESS.

uint32_t at24cxx_write_page	(	uint32_t	u32_page_address,
		uint32_t	u32_page_size,
		uint8_t const *	p_wr_buffer
	)

Write data to the specified page in AT24CXX.

Parameters

u32_page_address	The page number.
u32_page_size	The size of the page (which varies with the chips).
p_wr_buffer	Pointer to array where the bytes to be written are stored.

Returns

AT24C_WRITE_SUCCESS if the page was written, AT24C_WRITE_FAIL otherwise.

References twi_packet::addr, twi_packet::addr_length, at24c_build_word_address, AT24C_MEM_ADDR_LEN, AT24C_WRITE_FAIL, AT24C_WRITE_SUCCESS, at24cxx_acknowledge_polling(), BOARD_AT24C_ADDRESS, BOARD_AT24C_TWI_INSTANCE, twi_packet::buffer, twi_packet::chip, twi_packet::length, twi_master_write(), and TWI_SUCCESS.