nz_xEeprom.h File Reference

Interface for accessing an external SPI EEPROM. More...

#include "HardwareProfile.h"

Go to the source code of this file.

Macros
#define	XEE_SUCCESS   FALSE
#define	XEEInit   xeeInit
#define	XEEBeginWrite   xeeBeginWrite
#define	XEEWrite   xeeWrite
#define	XEEWriteArray   xeeWriteArray
#define	XEEEndWrite   xeeEndWrite
#define	XEEBeginRead   xeeBeginRead
#define	XEERead   xeeRead
#define	XEEReadArray   xeeReadArray
#define	XEEEndRead   xeeEndRead
#define	XEEIsBusy   xeeIsBusy
#define	xeeEndRead()

Typedefs
typedef BOOL	XEE_RESULT

Functions
void	xeeInit (void)
BOOL	xeeBeginWrite (DWORD address)
BOOL	xeeWrite (BYTE val)
void	xeeWriteArray (BYTE *val, WORD wLen)
BOOL	xeeEndWrite (void)
BOOL	xeeBeginRead (DWORD address)
BYTE	xeeRead (void)
BOOL	xeeReadArray (DWORD address, BYTE *buffer, WORD length)
BOOL	xeeIsBusy (void)

Detailed Description

Interface for accessing an external SPI EEPROM.

Author

Modtronix Engineering

Compiler:

MPLAB XC16

Description

Code for reading and writing to and from a external EEPROM chip on the SPI bus. This file defines an interface for an external SPI EEPROM chip. The implementation has to be done in a separate c file by creating instances of these functions. The Netcruzer library contains a default implementations which can be used.

External EEPROM Project Configuration

The following defines are used to configure this module, and should be placed in projdefs.h. Note that all items marked [-DEFAULT-] are defaults, and do not have to be placed in projdefs.h if they contain desired configuration! For details, see Project Configuration.

// *******************************************************
// ----------------- xEeprom Configuration -----------------
// ********************************************************
//#define XEEPROM_BUFFER_SIZE      (32)

External EEPROM Hardware Configuration

The following defines the hardware used for this module, and is located in the board specific file in the "netcruzer/lib" folder (brd_sbc66ec-r2.h for example). They should only be changed if the default EEPROM is replaced with a custom one.

// ********************************************************
// ------------ xEeprom Hardware Configuration ------------
// ********************************************************
#define XEEPROM_SIZE           (8192)      //Default EEPROM is 25LC640 = 64kBits = 8kBytes
#define XEEPROM_PAGE_SIZE      (32)

Software License Agreement

The software supplied herewith is owned by Modtronix Engineering, and is protected under applicable copyright laws. The software supplied herewith is intended and supplied to you, the Company customer, for use solely and exclusively on products manufactured by Modtronix Engineering. The code may be modified and can be used free of charge for commercial and non commercial applications. All rights are reserved. Any use in violation of the foregoing restrictions may subject the user to criminal sanctions under applicable laws, as well as to civil liability for the breach of the terms and conditions of this license.

THIS SOFTWARE IS PROVIDED IN AN 'AS IS' CONDITION. NO WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.

File History

2011-12-10, David H. (DH):

• Initial version, modified version of Microchip's nz_xEeprom.h file from their TCP/IP stack

Macro Definition Documentation

#define xeeEndRead

(

)

Ends read

Returns

TRUE if successful, else FALSE

Function Documentation

BOOL xeeBeginRead

(

DWORD

address)

Sets internal address counter to given address.

Parameters

address

Address at which read is to be performed.

Returns

TRUE if successful, else FALSE

BOOL xeeBeginWrite

(

DWORD

address)

Modifies internal address counter of EEPROM.

Parameters

address

address to be set for writing

Returns

TRUE if successful

BOOL xeeEndWrite

(

void

)

Commits any last uncommitted bytes in cache to physical storage. Call this function when you no longer need to write any more bytes at the selected address.

Pre-Condition:

xeeInit() && xeeBeginWrite() are already called.

Returns

TRUE if successful, else FALSE

void xeeInit

(

void

)

Initialize SPI module to communicate to serial EEPROM.

BOOL xeeIsBusy

(

void

)

Indicates if the external EEPROM is busy

Returns

TRUE if busy, FALSE if available

BYTE xeeRead

(

void

)

Reads next byte from EEPROM; internal address is incremented by one.

Pre-Condition:

xeeInit() && xeeBeginRead() are already called.

Returns

BYTE that was read

BOOL xeeReadArray	(	DWORD	address,
		BYTE *	buffer,
		WORD	length
	)

Reads desired number of bytes in sequential mode. This function performs all necessary steps and releases the bus when finished.

Pre-Condition:

xeeInit() is already called.

Parameters

address	Address from where array is to be read
buffer	Caller supplied buffer to hold the data
length	Number of bytes to read.

Returns

TRUE if successful, else FALSE

BOOL xeeWrite

(

BYTE

val)

Writes a byte to the write cache, and if full, commits the write. Also, if a write boundary is reached the write is committed. When finished writing, xeeEndWrite() must be called to commit any unwritten bytes from the write cache.

Pre-Condition:

xeeInit() && xeeBeginWrite() are already called.

Parameters

val	Byte to be written

Returns

TRUE if successful, else FALSE

void xeeWriteArray	(	BYTE *	val,
		WORD	wLen
	)

This function writes an array of bytes to the EEPROM at the address specified when xeeBeginWrite() was called. Page boundary crossing is handled internally.

Details: The internal write cache is flushed at completion, so it is unnecessary to call xeeEndWrite() after calling this function. However, if you do so, no harm will be done.

Pre-Condition:

xeeInit() was called once and xeeBeginWrite() was called.

Parameters

val	The array to write to the next memory location
wLen	The length of the data to be written