stm32_eeprom.c File Reference

Provides emulated eeprom from flash. More...

#include "stm32_eeprom.h"
#include "stm32yyxx_ll_utils.h"
#include <string.h>
#include <stdbool.h>

Macros
#define	EEPROM_FLASH_PAGE_NUMBER   ((uint32_t)(((LL_GetFlashSize() * 1024) / FLASH_PAGE_SIZE) - 1))
	Flash bank used for the EEPROM emulation.
#define	FLASH_BASE_ADDRESS   ((uint32_t)((FLASH_END + 1) - FLASH_PAGE_SIZE))
	Address of the last byte of the flash area used for the EEPROM emulation.

Functions
uint8_t	eeprom_read_byte (const uint32_t pos)
	Read a byte from the emulated EEPROM (flash).
void	eeprom_write_byte (uint32_t pos, uint8_t value)
	Write a byte to the emulated EEPROM (flash).
uint8_t	eeprom_buffered_read_byte (const uint32_t pos)
	Read a byte from the EEPROM buffer, flash is not read.
void	eeprom_buffered_write_byte (uint32_t pos, uint8_t value)
	Write a byte to the EEPROM buffer, flash is not updated.
void	eeprom_buffer_fill (void)
	Copy the data from flash into the EEPROM buffer.
void	eeprom_buffer_flush (void)
	Write the EEPROM buffer content into flash.
	HAL_FLASH_Lock ()

Variables
static uint8_t	eeprom_buffer [E2END+1] = {0}
	RAM copy of the emulated EEPROM, 8 bytes aligned for the flash programming.

Detailed Description

Provides emulated eeprom from flash.

Attention

Copyright (c) 2016-2021, STMicroelectronics All rights reserved.

This software component is licensed by ST under BSD 3-Clause license, the "License"; You may not use this file except in compliance with the License. You may obtain a copy of the License at: opensource.org/licenses/BSD-3-Clause

Macro Definition Documentation

EEPROM_FLASH_PAGE_NUMBER

#define EEPROM_FLASH_PAGE_NUMBER   ((uint32_t)(((LL_GetFlashSize() * 1024) / FLASH_PAGE_SIZE) - 1))

Flash bank used for the EEPROM emulation.

Can be overridden before including this file.

Flash sector used for the EEPROM emulation. Can be overridden before including this file.

Flash page number used for the EEPROM emulation. Can be overridden before including this file.

FLASH_BASE_ADDRESS

#define FLASH_BASE_ADDRESS   ((uint32_t)((FLASH_END + 1) - FLASH_PAGE_SIZE))

Address of the last byte of the flash area used for the EEPROM emulation.

Can be overridden.

Start address of the flash area used for the EEPROM emulation. Can be overridden.

By default, use the last page of the flash to store data in order to prevent overwriting program data.

Function Documentation

eeprom_buffer_fill()

void eeprom_buffer_fill

(

)

Copy the data from flash into the EEPROM buffer.

Note

Any pending change in the buffer which was not flushed is overwritten.

eeprom_buffer_flush()

void eeprom_buffer_flush

(

)

Write the EEPROM buffer content into flash.

Note

Use it after eeprom_buffered_write_byte() to make the changes persistent.

eeprom_buffered_read_byte()

uint8_t eeprom_buffered_read_byte

(

const uint32_t

pos

)

Read a byte from the EEPROM buffer, flash is not read.

Parameters

pos	Address to read.

Returns

Data read from the EEPROM buffer.

eeprom_buffered_write_byte()

void eeprom_buffered_write_byte	(	uint32_t	pos,
		uint8_t	value
	)

Write a byte to the EEPROM buffer, flash is not updated.

Parameters

pos	Address to write.
value	Value to write.

eeprom_read_byte()

uint8_t eeprom_read_byte

(

const uint32_t

pos

)

Read a byte from the emulated EEPROM (flash).

With a real data EEPROM, pos is a relative address and 0 is returned if it is out of range. Otherwise the flash content is first copied into the EEPROM buffer.

Parameters

pos	Address to read.

Returns

Data read from EEPROM.

eeprom_write_byte()

void eeprom_write_byte	(	uint32_t	pos,
		uint8_t	value
	)

Write a byte to the emulated EEPROM (flash).

With a real data EEPROM, pos is a relative address and the write is ignored if it is out of range. Otherwise the byte is written to the EEPROM buffer, then the whole buffer is written into flash.

Parameters

pos	Address to write.
value	Value to write.