/**************************************************************************//**
* \brief EEPROM 24C512 library.
* \author Copyright (C) 2012 Julien Le Sech - www.idreammicro.com
* \version 1.0
* \date 20121031
*
* This file is part of the iDreamMicro library.
*
* This library is free software: you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License as published by the Free
* Software Foundation, either version 3 of the License, or (at your option) any
* later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see http://www.gnu.org/licenses/
******************************************************************************/
/**************************************************************************//**
* \file eeprom_24c512.c
******************************************************************************/
/******************************************************************************
* Header file inclusions.
******************************************************************************/
#include "../eeprom_24c512.h"
#include <twi/twi.h>
#include <util/delay.h>
#include <assert.h>
#include <stdint.h>
#include <stdlib.h>
/******************************************************************************
* Private macro definitions.
******************************************************************************/
/**************************************************************************//**
* \def EEPROM_24C512__ADDRESS
* \brief EEPROM 24C512 address. Given by datasheet.
******************************************************************************/
#define EEPROM_24C512__ADDRESS 0xA0
/**************************************************************************//**
* \def EEPROM_24C512__PAGE_SIZE
* \brief Size of a page in EEPROM memory.
* This size is given by EEPROM memory datasheet.
******************************************************************************/
#define EEPROM_24C512__PAGE_SIZE 128
/******************************************************************************
* Private function prototypes.
******************************************************************************/
/**************************************************************************//**
* \fn static void eeprom_24c512__write_page(
* uint16_t address,
* uint8_t length,
* uint8_t* p_data)
*
* \brief Write a page in memory.
*
* \param address Start address of data to write.
* \param length Number of bytes to write.
* \param[in] p_data Bytes to write.
******************************************************************************/
static
void
eeprom_24c512__write_page
(
uint16_t address
,
uint8_t length
,
uint8_t* p_data
);
/******************************************************************************
* Private variable declarations.
******************************************************************************/
static uint8_t device_address
= 0;
/******************************************************************************
* Public function definitions.
******************************************************************************/
/**************************************************************************//**
* \fn void eeprom_24c512__initialize(uint8_t hardware_address)
*
* \brief Initialize EEPROM 24C512.
*
* \param hardware_address Hardware address. Pins A0 to A1.
******************************************************************************/
void
eeprom_24c512__initialize
(
uint8_t hardware_address
){
// Compute device address.
device_address
= EEPROM_24C512__ADDRESS
| ((hardware_address
& 0x03) << 1);
// We don't initialize TWI here: we may have several devices on the bus.
// Initialize TWI.
//twi__initialize(EEPROM_24C512__CLOCK_RATE);
}
/**************************************************************************//**
* \fn void eeprom_24c512__write_byte(uint16_t address, uint8_t data)
*
* \brief Write a byte into memory.
*
* \param address Address in memory.
* \param data Byte to write.
******************************************************************************/
void
eeprom_24c512__write_byte
(
uint16_t address
,
uint8_t data
){
twi__start
();
twi__send_slaw
(device_address
);
twi__send_data
(address
>> 8);
twi__send_data
(address
& 0xFF);
twi__send_data
(data
);
twi__stop
();
}
/**************************************************************************//**
* \fn void eeprom_24c512__write_bytes(
* uint16_t address,
* uint16_t length,
* uint8_t* p_data)
*
* \brief Write bytes into memory.
*
* \param address Start address.
* \param length Number of bytes to write.
* \param[in] p_data Bytes to write.
******************************************************************************/
void
eeprom_24c512__write_bytes
(
uint16_t address
,
uint16_t length
,
uint8_t* p_data
){
// Check the preconditions.
assert(NULL
!= p_data
);
// Write first page if not aligned.
uint8_t not_aligned_length
= 0;
uint8_t page_offset
= address
% EEPROM_24C512__PAGE_SIZE
;
if (page_offset
> 0)
{
not_aligned_length
= EEPROM_24C512__PAGE_SIZE
- page_offset
;
eeprom_24c512__write_page
(address
, not_aligned_length
, p_data
);
length
-= not_aligned_length
;
}
if (length
> 0)
{
address
+= not_aligned_length
;
p_data
+= not_aligned_length
;
// Write complete and aligned pages.
uint16_t page_count
= length
/ EEPROM_24C512__PAGE_SIZE
;
for (uint16_t i
= 0; i
< page_count
; i
++)
{
eeprom_24c512__write_page
(address
, EEPROM_24C512__PAGE_SIZE
, p_data
);
address
+= EEPROM_24C512__PAGE_SIZE
;
p_data
+= EEPROM_24C512__PAGE_SIZE
;
length
-= EEPROM_24C512__PAGE_SIZE
;
}
if (length
> 0)
{
// Write remaining uncomplete page.
eeprom_24c512__write_page
(address
, length
, p_data
);
}
}
}
/**************************************************************************//**
* \fn uint8_t eeprom_24c512__read_byte(uint16_t address)
*
* \brief Read a byte in memory.
*
* \param address Address to read.
*
* \return Read byte.
******************************************************************************/
uint8_t
eeprom_24c512__read_byte
(
uint16_t address
){
uint8_t data
= 0;
twi__start
();
twi__send_slaw
(device_address
);
twi__send_data
(address
>> 8);
twi__send_data
(address
& 0xFF);
twi__repeat_start
();
twi__send_slar
(device_address
);
twi__receive_data_nack
(&data
);
twi__stop
();
return data
;
}
/**************************************************************************//**
* \fn void eeprom_24c512__read_bytes(
* uint16_t address,
* uint16_t length,
* uint8_t* p_data)
*
* \brief Read bytes in memory.
*
* \param address Start address of data to read.
* \param length Number of bytes to read.
* \param[in] p_data Buffer to fill with read bytes.
******************************************************************************/
void
eeprom_24c512__read_bytes
(
uint16_t address
,
uint16_t length
,
uint8_t* p_data
){
// Check the preconditions.
assert(NULL
!= p_data
);
twi__start
();
twi__send_slaw
(device_address
);
twi__send_data
(address
>> 8);
twi__send_data
(address
& 0xFF);
twi__repeat_start
();
twi__send_slar
(device_address
);
for (uint16_t i
= 0; i
< length
- 1; i
++)
{
twi__receive_data_ack
(p_data
+ i
);
}
twi__receive_data_nack
(p_data
+ length
- 1);
twi__stop
();
}
/******************************************************************************
* Private function definitions.
******************************************************************************/
/**************************************************************************//**
* \fn static void eeprom_24c512__write_page(
* uint16_t address,
* uint8_t length,
* uint8_t* p_data)
*
* \brief Write a page in memory.
*
* \param address Start address of data to write.
* \param length Number of bytes to write.
* \param[in] p_data Bytes to write.
******************************************************************************/
static
void
eeprom_24c512__write_page
(
uint16_t address
,
uint8_t length
,
uint8_t* p_data
){
// Check the preconditions.
assert(NULL
!= p_data
);
twi__start
();
twi__send_slaw
(device_address
);
twi__send_data
(address
>> 8);
twi__send_data
(address
& 0xFF);
for (uint8_t i
= 0; i
< length
; i
++)
{
twi__send_data
(p_data
[i
]);
}
twi__stop
();
// Write cycle time (tWR). See EEPROM memory datasheet for more details.
_delay_ms
(10);
}