at49bv.c File Reference

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Detailed Description

Routines for Atmel AT49 flash memory chips.

 *
 * $Log: at49bv.c,v $
 * Revision 1.3  2006/10/08 16:48:09  haraldkipp
 * Documentation fixed
 *
 * Revision 1.2  2006/05/25 09:33:35  haraldkipp
 * Bugfix. At49bvParamWrite() returned an error when flash sector contents
 * was equal to the contents to write.
 *
 * Revision 1.1  2006/04/07 13:51:36  haraldkipp
 * AT49BV flash memory support added. A single sector may be used to
 * store system configurations in case there is no EEPROM available.
 *
 *
 * 

Defines
#define	FLASH_CHIP_BASE   0x10000000
	Base address of the flash memory chip.
#define	FLASH_CONF_SECTOR   0x6000
	Address offset of the configuration sector.
#define	FLASH_CONF_SIZE   512
	Size of the configuration area.
#define	FLASH_ERASE_WAIT   3000
#define	FLASH_CHIP_ERASE_WAIT   50000
#define	FLASH_WRITE_POLLS   1000
#define	FLASH_UNLOCK(base)
#define	FLASH_COMMAND(base, cmd)
#define	FLASH_CMD_ERASE   0x80
#define	FLASH_CMD_ERASE_CHIP   0x10
#define	FLASH_CMD_ERASE_SECTOR   0x30
#define	FLASH_CMD_ENTER_ID   0x90
#define	FLASH_CMD_EXIT_ID   0xF0
#define	FLASH_CMD_PROGRAM   0xA0
Typedefs
typedef unsigned short	flashdat_t
typedef unsigned long	flashadr_t
typedef volatile flashdat_t *	flashptr_t
Functions
unsigned long	At49bvInit (void)
int	At49bvSectorErase (u_int off)
	Erase sector at the specified offset.
int	At49bvChipErase (void)
	Erase entire flash memory chip.
int	At49bvSectorRead (u_int off, void *data, u_int len)
	Read data from flash memory.
int	At49bvSectorWrite (u_int off, CONST void *data, u_int len)
	Write data into flash memory.
int	At49bvParamRead (u_int pos, void *data, u_int len)
	Load configuration parameters from flash memory.
int	At49bvParamWrite (u_int pos, CONST void *data, u_int len)
	Store configuration parameters in flash memory.

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Define Documentation

#define FLASH_CONF_SIZE   512

Size of the configuration area. During write operations a buffer with this size is allocated from heap and may cause memory problems with large sectors. Thus, this value may be less than the size of the configuration sector, in which case the rest of the sector is unused.

#define FLASH_UNLOCK (  base   )

Value: { \ base[0x0555] = 0xAA; \ base[0x0AAA] = 0x55; \ }

#define FLASH_COMMAND (  base, cmd   )

Value: { \ base[0x0555] = cmd; \ }

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Function Documentation

int At49bvSectorRead (  u_int  off, void *  data, u_int  len )

Read data from flash memory. Parameters: off  Start location within the chip, starting at 0. data  Points to a buffer that receives the data. len  Number of bytes to read. Returns: 0 on success or -1 in case of an error.

int At49bvSectorWrite (  u_int  off, CONST void *  data, u_int  len )

Write data into flash memory. The related sector must have been erased before calling this function. Parameters: off  Start location within the chip, starting at 0. data  Points to a buffer that contains the bytes to be written. len  Number of bytes to write. Returns: 0 on success or -1 in case of an error.

int At49bvParamRead (  u_int  pos, void *  data, u_int  len )

Load configuration parameters from flash memory. Parameters: pos  Start location within configuration sector. data  Points to a buffer that receives the contents. len  Number of bytes to read. Returns: Always 0.

int At49bvParamWrite (  u_int  pos, CONST void *  data, u_int  len )

Store configuration parameters in flash memory. Parameters: pos  Start location within configuration sector. data  Points to a buffer that contains the bytes to store. len  Number of bytes to store. Returns: 0 on success or -1 in case of an error.

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