AVR internal EEPROM read and write program - write data first, then read it out to see if it is consistent

/*This program is to perform read and write operations on the internal EEPROM of the AVR to test the EEPROM. The main purpose is to first write to */

/*Write data into the internal EEPROM, then read it out to see if it is consistent. Finally, it is proven to be correct. This program can be used*/

/*20110414 Tianjin Fourth Project Department Dormitory Wang Junwei*/

#include

#define uchar unsigned char

#define uint unsigned int

#define set_bit(a,b) a|=(1<#define clr_bit(a,b) a&=~(1<#define get_bit(a,b) a&(1<

void write_eeprom (uchar add,uchar date) // write EEPROM

{

        while(get_bit(EECR,1));//Check if EEWE=0 is there a write operation? If =1, then wait; if =0, then it proves that it is idle and can be written down.

         EEARH=0;//Not used

   EEARL=add; //Address preparation

   EEDR=date; //Data preparation

   clr_bit(EECR,3); //Disable EEPROM interrupt

   SREG=0; //Disable general interruption to prevent sudden interruption from interrupting the CPU's EEPROM write operation

   set_bit(EECR,2); //Turn on the master write enable bit

   set_bit(EECR,1); //enable write enable bit

   ;;;;;//Write to the on-chip EEPROM

}

uchar read_eeprom(uchar add) //Read EEPROM

{

while(get_bit(EECR,1));//Check if EEWE=0 is there a write operation? If =1, then wait; if =0, then it proves that it is idle and can be written down.

EEARH=0;//Not used

EEARL=add; //Address preparation

SREG=0; //Disable general interruption to prevent sudden interruption from interrupting the CPU's EEPROM reading operation

set_bit(EECR,0); //Start read operation

;;;;//wait

return (EEDR);

}

void main () //Main function

{

DDRA=0xff;

PORTA=0x00; //Port A initialization

write_eeprom(0x00,0x88); //Write the first eight bits of address 0x00; and data 0x33; Note that I did not use EEARH, only EERHL, so I can only search for 256 bytes

PORTA=read_eeprom(0x00);//address inside brackets

}