25AAxxxx/25LCxxxx EEPROM

Functions
ssize_t	eeprom_spi_command (eeprom_25xxx_t eeprom, uint8_t *cmd, uint8_t len)
	Sends a generic command to the SPI memory. More...
ssize_t	eeprom_spi_erase (eeprom_25xxx_t eeprom, uint32_t addr, size_t len)
	Erases an array of bytes in the EEPROM. Erase Page command is used. More...
ssize_t	eeprom_spi_read (eeprom_25xxx_t eeprom, void *rxbuf, uint32_t addr, size_t len)
	Reads the specified number of bytes from the EEPROM. More...
ssize_t	eeprom_spi_read_status (eeprom_25xxx_t eeprom)
	Reads the status register of the memory. More...
ssize_t	eeprom_spi_write (eeprom_25xxx_t eeprom, uint8_t *data, uint32_t addr, size_t len)
	Writes an array of bytes in the EEPROM. More...
ssize_t	eeprom_spi_write_enable (eeprom_25xxx_t eeprom)
	Sets the Write-Enable Latch in the memory. More...

Detailed Description

Platform-specific layer provides a consistent Virtual EEPROM API to upper layers of the driver.

EEPROM API Overview

This API contains the functions to initialize and control 25AAxxxx/25LCxxxx family of EEPROMs (25xx010/25xx020/25xx040/25xx080/25xx160/25xx320/25xx640/25xx128/25xx256/25xx512/25xx1024) of for the Programmable XBee devices. These EEPROMs are user-modifiable read-only memories (ROM) that are connected to the XBee modules trough the SPI interface. They can be erased and reprogrammed (written to) repeatedly.

• Functions to read/write/erase the 25xxx EEPROMs:
  • eeprom_spi_write()
  • eeprom_spi_erase()
  • eeprom_spi_read()
  • eeprom_spi_write_enable()
  • eeprom_spi_command()
  • eeprom_spi_read_status()

Platform-specific layer provides a consistent MACROS API to upper layers of the driver.

25AA/25LC SPI EEPROMs macros

The 25AA/25LC EEPROMs have 11 commands, which may be used along the eeprom_spi_command() function. Such commands are defined by the following macros: -SPI EEPROM 25AA/25LC commands:

• EEPROM_WREN : Set the write enable latch (enable write operations).
• EEPROM_WRITE : Write data to memory array beginning at selected address.
• EEPROM_READ : Read data from memory array beginning at selected address.
• EEPROM_WRDI : Reset the write enable latch (disable write operations).
• EEPROM_RDSR : Read STATUS register.
• EEPROM_WRSR : Write STATUS register.
• EEPROM_PE : Page Erase - erase one page in memory array.
• EEPROM_SE : Sector Erase - erase one sector in memory array.
• EEPROM_CE : Chip Erase - erase all sectors in memory array.
• EEPROM_RDID : Release from Deep power-down and read electronic signature.
• EEPROM_DPD : Deep Power-Down mode.

Also, the status-register's bits are defined by the following macros: -SPI EEPROM 25AA/25LC status register bits:

• EEPROM_SR_WIP : Write-In-Progress bit.
• EEPROM_SR_WEL : Write-Enable-Latch bit.
• EEPROM_SR_WPEN : Write-Protect-Enable bit.
• EEPROM_SR_BP : Block-Protecion bit.

Function Documentation

ssize_t eeprom_spi_command	(	eeprom_25xxx_t	eeprom,
		uint8_t *	cmd,
		uint8_t	len
	)

Sends a generic command to the SPI memory.

Parameters

[in]	eeprom	eeprom index to configure (use the name of the component defined by the config.xml)
[in]	cmd	buffer containing the bytes to be written. This may be one of the 25AA/25LC SPI EEPROMs macros defined.
[in]	len	number of bytes to write from the buffer.

Return values

<0	if there is an error while writing in the EEPROM.

ssize_t eeprom_spi_erase	(	eeprom_25xxx_t	eeprom,
		uint32_t	addr,
		size_t	len
	)

Erases an array of bytes in the EEPROM. Erase Page command is used.

Parameters

[in]	eeprom	eeprom index to configure (use the name of the component defined by the config.xml)
[in]	addr	address of the EEPROM to start the erasing process.
[in]	len	number of bytes to write from the buffer.

Return values

ssize_t	number of bytes that were erased.
ERANGE	out of range
<0	if there is an error while erasing in the EEPROM.

ssize_t eeprom_spi_read	(	eeprom_25xxx_t	eeprom,
		void *	rxbuf,
		uint32_t	addr,
		size_t	len
	)

Reads the specified number of bytes from the EEPROM.

Parameters

[in]	eeprom	eeprom index to configure (use the name of the component defined by the config.xml)
[out]	rxbuf	buffer where the read bytes will be stored.
[in]	addr	address of the EEPROM to start reading from.
[in]	len	number of bytes to read from the EEPROM.

Return values

ssize_t	the number of bytes read.
ERANGE	out of range.
<0	if there is an error while reading the EEPROM.

ssize_t eeprom_spi_read_status

(

eeprom_25xxx_t

eeprom

)

Reads the status register of the memory.

Parameters

[in]	eeprom	eeprom index to configure (use the name of the component defined by the config.xml)
[in]	cmd	buffer containing the bytes to be written.
[in]	len	number of bytes to write from the buffer.

Return values

Returns	the status register.
<0	if there is an error while writing in the EEPROM.

ssize_t eeprom_spi_write	(	eeprom_25xxx_t	eeprom,
		uint8_t *	data,
		uint32_t	addr,
		size_t	len
	)

Writes an array of bytes in the EEPROM.

Parameters

[in]	eeprom	eeprom index to configure (use the name of the component defined by the config.xml)
[in]	data	buffer containing the bytes to be written.
[in]	addr	address of the EEPROM to start the writing process.
[in]	len	number of bytes to write from the buffer.

Return values

ssize_t	number of bytes that where written.
ERANGE	out of range
<0	if there is an error while writing in the EEPROM.

ssize_t eeprom_spi_write_enable

(

eeprom_25xxx_t

eeprom

)

Sets the Write-Enable Latch in the memory.

Parameters

[in]

eeprom

eeprom index to configure (use the name of the component defined by the config.xml)

Return values

<0	if there is an error while writing in the EEPROM.