找到一个国外人写的at24c1024的c51读写程序

cpubbs

原贴地址:http://www.edaboard.com/topic293845.html

24XX512.h


#include "i2c.h" /* Need i2c bus */

#define EEPROMS_ID 0xA0 /* Microchip 24xx512 */

unsigned char EEPROM_get(unsigned int addr)
{
unsigned char dat;

I2C_start(); /* Start i2c bus */

I2C_write(EEPROMS_ID); /* Connect to EEPROM */
I2C_write(addr&0xF0); /* Request RAM address (Hight byte) */
I2C_write(addr&0x0F); /* Request RAM address (Low byte) */

I2C_start(); /* Start i2c bus */

I2C_write(EEPROMS_ID+1);/* Connect to EEPROM for Read */
dat = I2C_read(); /* Receive data */

I2C_noack();

I2C_stop(); /* Stop i2c bus */

return dat;
}

void EEPROM_set(unsigned int addr, unsigned char val)
{
I2C_start();

I2C_write(EEPROMS_ID); /* Connect to EEPROM */
I2C_write(addr&0xF0); /* Request RAM address (Hight byte) */
I2C_write(addr&0x0F); /* Request RAM address (Low byte) */

I2C_write(val); /* Write sec on RAM specified address */

I2C_stop(); /* Stop i2c bus */
}

Added after 2 minutes:

i2c.h

#define SDA P2_2 /* Set P2.7 = SDA */
#define SCL P2_3 /* Set P2.6 = SCL */
#define I2C_DELAY 0x0F /* For delay i2c bus */

void I2C_delay(void)
{
unsigned char i;

for(i=0; i<I2C_DELAY; i++);
}

void I2C_clock(void)
{
I2C_delay();

SCL = 1; /* Start clock */

I2C_delay();

SCL = 0; /* Clear SCL */
}

void I2C_start(void)
{
if(SCL)
SCL = 0; /* Clear SCL */

SDA = 1; /* Set SDA */
SCL = 1; /* Set SCL */

I2C_delay();

SDA = 0; /* Clear SDA */

I2C_delay();

SCL = 0; /* Clear SCL */
}

void I2C_stop(void)
{
if(SCL)
SCL = 0; /* Clear SCL */

SDA = 0; /* Clear SDA */
I2C_delay();

SCL = 1; /* Set SCL */

I2C_delay();

SDA = 1; /* Set SDA */
}

bit I2C_write(unsigned char dat)
{
bit data_bit;
unsigned char i;

for(i=0;i<8;i++) /* For loop 8 time(send data 1 byte) */
{
data_bit = dat & 0x80; /* Filter MSB bit keep to data_bit */
SDA = data_bit; /* Send data_bit to SDA */

I2C_clock(); /* Call for send data to i2c bus */

dat = dat<<1;
}

SDA = 1; /* Set SDA */

I2C_delay();

SCL = 1; /* Set SCL */

I2C_delay();

data_bit = SDA; /* Check acknowledge */
SCL = 0; /* Clear SCL */

I2C_delay();

return data_bit; /* If send_bit = 0 i2c is valid */
}

unsigned char I2C_read(void)
{
bit rd_bit;
unsigned char i, dat;

dat = 0x00;

for(i=0;i<8;i++) /* For loop read data 1 byte */
{
I2C_delay();

SCL = 1; /* Set SCL */

I2C_delay();

rd_bit = SDA; /* Keep for check acknowledge */
dat = dat<<1;
dat = dat | rd_bit; /* Keep bit data in dat */

SCL = 0; /* Clear SCL */
}

return dat;
}

void I2C_ack()
{
SDA = 0; /* Clear SDA */

I2C_delay();

I2C_clock(); /* Call for send data to i2c bus */

SDA = 1; /* Set SDA */
}

void I2C_noack()
{
SDA = 1; /* Set SDA */

I2C_delay();

I2C_clock(); /* Call for send data to i2c bus */

SCL = 1; /* Set SCL */
}

Added after 49 seconds:

main

#include <AT89X51.H>
#include <24xx512.h>

unsigned int del,i,x,temp;

char getCharacter (void)
{
char chr; // variable to hold the new character
while (RI != 1) {;}
chr = SBUF;
RI = 0;
return(chr);
}
void send (char a)
{
SBUF = a;
while (TI != 1);
TI=0;
}

void main (void){
char chr;
int i=0,j=0,count=0,inc=47;//inc=47
int index=0;
P1=0X00;
P2=0X00;

SCON = 0x50; // mode 1, 8-bit uart, enable receiver
TMOD = 0x20; // timer 1, mode 2, 8-bit reload
TH1 = 0XE6; // 1200
TL1 = 0XE6;
TR1 = 1;
TI = 0;
SBUF =0;

while(1){
your code

}
}