---

EEPROM handling

avr-libc declarations
#define	eeprom_is_ready()   bit_is_clear(EECR, EEWE)
unsigned char	eeprom_rb (unsigned int addr)
unsigned int	eeprom_rw (unsigned int addr)
void	eeprom_wb (unsigned int addr, unsigned char val)
void	eeprom_read_block (void *buf, unsigned int addr, size_t n)
IAR C compatibility defines
#define	_EEPUT(addr, val)   eeprom_wb(addr, val)
#define	_EEGET(var, addr)   (var) = eeprom_rb(addr)

---

Detailed Description

#include <avr/eeprom.h> 

This header file declares the interface to some simple library routines suitable for handling the data EEPROM contained in the AVR microcontrollers. The implementation uses a simple polled mode interface. Applications that require interrupt-controlled EEPROM access to ensure that no time will be wasted in spinloops will have to deploy their own implementation.

Note:

All of the read/write functions first make sure the EEPROM is ready to be accessed. Since this may cause long delays if a write operation is still pending, time-critical applications should first poll the EEPROM e. g. using eeprom_is_ready() before attempting any actual I/O.

---

Define Documentation

#define _EEGET (  var, addr    )     (var) = eeprom_rb(addr)

read a byte from EEPROM

#define _EEPUT (  addr, val    )     eeprom_wb(addr, val)

write a byte to EEPROM

#define eeprom_is_ready (    )     bit_is_clear(EECR, EEWE)

return 1 if EEPROM is ready for a new read/write operation, 0 if not

---

Function Documentation

unsigned char eeprom_rb (  unsigned int    addr )

read one byte from EEPROM address addr

void eeprom_read_block (  void *    buf, unsigned int    addr, size_t    n )

read a block of n bytes from EEPROM address addr to buf

unsigned int eeprom_rw (  unsigned int    addr )

read one 16-bit word (little endian) from EEPROM address addr

void eeprom_wb (  unsigned int    addr, unsigned char    val )

write a byte val to EEPROM address addr

---