ATxmega256A3_EEPROM.c File Reference

Writing EEPROM and Flash in ATxmega256A3 / ATxmega256A3B - Rev B. More...

#include "avr_compiler.h"

Go to the source code of this file.

Defines
#define	PAGESIZE   32
Functions
void	EEPROM_write_page (uint8_t *page, uint8_t page_no)
	ISR (NVM_EE_vect)
int	main (void)

---

Detailed Description

Writing EEPROM and Flash in ATxmega256A3 / ATxmega256A3B - Rev B.

This file contains an example application that demonstrates Self-programming for ATxmega256A3 / ATxmega256A3B - Rev B.

Application note:

AVR1008: Writing EEPROM and Flash in ATxmega256A3 / ATxmega256A3B - Rev B

Documentation

For comprehensive code documentation, supported compilers, compiler settings and supported devices see readme.html

Author:

Atmel Corporation: http://www.atmel.com
Support email: avr@atmel.com

Revision

2742

Date

2009-09-02 13:39:09 +0200 (on, 02 sep 2009)

Copyright (c) 2009, Atmel Corporation All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

3. The name of ATMEL may not be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Definition in file ATxmega256A3_EEPROM.c.

---

Define Documentation

#define PAGESIZE   32

Definition at line 52 of file ATxmega256A3_EEPROM.c.

Referenced by EEPROM_write_page(), and main().

---

Function Documentation

void EEPROM_write_page	(	uint8_t *	page,
		uint8_t	page_no
	)

Definition at line 94 of file ATxmega256A3_EEPROM.c.

References PAGESIZE.

Referenced by main().

{
        /* Set the NVM command to load to the EEPROM buffer */
        NVM.CMD = NVM_CMD_LOAD_EEPROM_BUFFER_gc;
        
        /* Max buffersize is PAGESIZE, hence the upper addresses are not needed */
        NVM.ADDR2 = 0;
        NVM.ADDR1 = 0;  

        /* Load buffer with data */
        for(int i = 0; i < PAGESIZE; i++)
        {
                /* Set the location where data is going to be put in the buffer */
                NVM.ADDR0 = i;
                /* Writing to the DATA register will trigger a write to the buffer */
                NVM.DATA0 = page[i];
        }
        
        /* Load the NVM command with erase and then write EEPROM page */
        NVM.CMD = NVM_CMD_ERASE_WRITE_EEPROM_PAGE_gc;

        /* Calculate address */
        uint16_t address = (uint16_t)(page_no*PAGESIZE);

        /* Set address to write to. */
        NVM.ADDR0 = address & 0xFF;
        NVM.ADDR1 = (address >> 8) & 0x1F;
        NVM.ADDR2 = 0x00;

        /* Save the Sleep register */
        uint8_t sleepCtr = SLEEP.CTRL;
        /* Set sleep mode to IDLE */
        SLEEP.CTRL = (SLEEP.CTRL & ~SLEEP.CTRL) | SLEEP_SMODE_IDLE_gc; 
        /* Save the PMIC Status and control registers */
        uint8_t statusStore = PMIC.STATUS;                                                              
        uint8_t pmicStore = PMIC.CTRL;          
        
        /* Enable only the highest level of interrupts */                                                                       
        PMIC.CTRL = (PMIC.CTRL & ~PMIC_HILVLEN_bm) | PMIC_HILVLEN_bm;
        /* Save SREG for later use */
        uint8_t globalInt = SREG;
        /* Enable global interrupts */
        sei();
        /* Set sleep enabled */
        SLEEP.CTRL |= SLEEP_SEN_bm; 
        /* Save eeprom interrupt settings for later */ 
        uint8_t eepromintStore = NVM.INTCTRL;
        
        
        /* Write the "safety code" to the CCP regiter */
        /* EEPROM write has to be executed within 4 cycles */
        CCP = CCP_IOREG_gc;
        /* Execute command to write buffer page to EEPROM */
        NVM.CTRLA = NVM_CMDEX_bm;
        /* Enable EEPROM interrupt */
        NVM.INTCTRL =  NVM_EELVL0_bm | NVM_EELVL1_bm;
        /* Sleep before 2.5uS has passed */
        __sleep();
        
        
        /* Restore sleep settings */
        SLEEP.CTRL = sleepCtr;
        /* Restore PMIC status and control registers */
        PMIC.STATUS = statusStore;
        PMIC.CTRL = pmicStore;
        /* Restore EEPROM interruptsettings */
        NVM.INTCTRL = eepromintStore;
        /* Restore global interrupt settings */
        SREG = globalInt;
}

ISR

(

NVM_EE_vect

)

Definition at line 63 of file ATxmega256A3_EEPROM.c.

{
        /* Disable the EEPROM interrupt */
        NVM.INTCTRL = (NVM.INTCTRL & ~NVM_EELVL_gm);
        return;
}

int main

(

void

)

Definition at line 72 of file ATxmega256A3_EEPROM.c.

References EEPROM_write_page(), and PAGESIZE.

{
        uint8_t eeprom_page[PAGESIZE];

        /* Just create some data to put in the EEPROM */
        for(int i = 0; i < PAGESIZE; i++)
        {
                eeprom_page[i] = i;
        }
        
        /* Call to the write page function */
        /* Write the contents of eeprom_page to EEPROM page nr. 2 */
        EEPROM_write_page(eeprom_page, 2);
        
        
        while(1){}      
}