51 MCU IIC & EEPROM driver

#include

#include "./delay/delay.h"

sbit SCL = P2^0;

sbit SDA = P2^1;

bit ack = 0;

unsigned char flag = 1;

#define LCDPORT P0

#define LCD_WRITE_DATA 1

#define LCD_WRITE_COM 0

sbit RS = P2^4;

sbit RW = P2^5;

sbit E = P2^6;

#define SUCC 0

#define ERR 1

void iic_start()

{

SDA = 1; //Operate SDA first, then SCL

  SCL = 1;

  delay_us(1);

  SDA = 0;

delay_us(1);

  SCL = 0; //Clamp the bus

}

void iic_stop()

{

SDA = 0;

SCL = 1;

delay_us(1);

SDA = 1;

delay_us(1);

SCL = 0; //Clamp the bus

}

bit iic_send_byte(unsigned char byte) //Send data, send high bit first, then send low bit. Only send one byte

{

unsigned char i;

for(i = 0; i < 8; i++)

{

SDA = byte & 0x80; //When the AND bit is non-zero, SDA = 1; When the AND bit is zero, SDA = 0;

SCL = 1;

delay_us(1); //delay 1us

  SCL = 0;

  byte <<= 1;

}

SCL = 1;

SDA = 1;

delay_us(2);

if(0 == SDA)

{

ack = 1;

}

else

{

ack = 0;

}

SCL = 0;

return ack;

}

unsigned char iic_rcv_byte() //Receive data

{

unsigned char i;

unsigned char temp = 0;

unsigned char a;

SDA = 1;

for(i = 0; i < 8; i++)

{

SCL = 0;

delay_us(1);

SCL = 1;

if(SDA)

{

a = 0x01;

}

else

{

a = 0;

}

temp |= (a << (7 - i));

delay_us(1);

}

SCL = 0;

return temp;

}

void iic_ack() //response signal

{

SDA = 0; //Pull the data bus low

SCL = 1; // Clock bus pull high

delay_us(1);

SCL = 0; //Clamp the bus

}

void iic_noack() //non-response signal

{

SDA = 1; //Release data bus

SCL = 1; //Pull up the clock bus

delay_us(1);

SCL = 0; //Clamp the bus

}

unsigned char AT24c02_send_byte(unsigned char devaddr, unsigned char romaddr, unsigned char *s, unsigned char num)     //发送字符串

{

unsigned char i;

iic_start(); //Start signal

iic_send_byte(devaddr); //Write hardware address

if(0 == ack) //wait for response

{

return ERR;

}

iic_send_byte(romaddr); //write physical address

if(0 == ack) //wait for response

{

return ERR;

}

for(i = 0; i < num; i++) //Send num characters

{

iic_send_byte(*s); //Send byte by byte

if(0 == ack)

{

return ERR;

}

s++;

}

iic_stop();

return SUCC;

}

unsigned char AT24c02_rcv_byte(unsigned char devaddr, unsigned char romaddr, unsigned char *s, unsigned char num)

{

unsigned char i;

iic_start();

delay_us(10);

iic_send_byte(devaddr); //Write hardware address

if(0 == ack) //wait for response

{

return ERR;

}

iic_send_byte(romaddr); //write physical address

if(0 == ack) //wait for response

{

return ERR;

}

iic_start();

iic_send_byte(devaddr + 1);

if(0 == ack) //wait for response

{

return ERR;

}

for(i = 0; i < num -1; i++) //Start reading data

{

*s = iic_rcv_byte();

iic_ack();

s++;

}

*s = iic_rcv_byte();

iic_noack();

  delay_us(10);

iic_stop();

return SUCC;

}

void lcd1602_write(unsigned char byte, unsigned char flag)

{

if(flag)

{

RS = 1; 

}

else

{

RS = 0;     

}

RW = 0;     

E = 1;      

LCDPORT = byte;

delay_ms(5);

E = 0;   

}

void lcd_init()

{

delay_ms(15);

  lcd1602_write(0x38,LCD_WRITE_COM);

  delay_ms(5);

  lcd1602_write(0x38,LCD_WRITE_COM);

  delay_ms(5);

  lcd1602_write(0x38,LCD_WRITE_COM);

  delay_ms(5);

  lcd1602_write(0x38,LCD_WRITE_COM);

  delay_ms(5);

  lcd1602_write(0x08,LCD_WRITE_COM);

  delay_ms(5);

  lcd1602_write(0x01,LCD_WRITE_COM);

  delay_ms(5);

  lcd1602_write(0x06,LCD_WRITE_COM);

  delay_ms(5);

  lcd1602_write(0x0c,LCD_WRITE_COM);

  delay_ms(5);

}

void lcd_dis_char(unsigned char x, unsigned char y, unsigned char *str)

{

if((x > 15) || (y > 1))

{

return ;

}

if(0 == y)

{

lcd1602_write(0x80 + x, LCD_WRITE_COM);

}

else 

{

lcd1602_write(x + 0xc0,LCD_WRITE_COM);

}

while(*str != '')

{

lcd1602_write(*str , LCD_WRITE_DATA);

str++;

}

}

void main()

{

//unsigned char i;

unsigned char test[10] = {'0','1','2','3','4','5','6','7','8','9'};

unsigned char temp[11];

lcd_init();

AT24c02_send_byte(0xae,100,test,10);

delay_s(1);

AT24c02_rcv_byte(0xae,100,temp,10);

temp[10] = '';

lcd_dis_char(0,0,temp);

lcd_dis_char(0,1,temp);

while(1)

{

}

}