AT24C04.h 代码

sbit ATCLK=P1^6;
sbit SDA=P1^7;
sbit a7=ACC^7;
sbit a6=ACC^6;
sbit a5=ACC^5;
sbit a4=ACC^4;
sbit a3=ACC^3;
sbit a2=ACC^2;
sbit a1=ACC^1;
sbit a0=ACC^0;
/*********************
*******24C04的初始化**
**** **************/
void init_24C04()
{
SDA=1;
_nop_();
ATCLK=1;
_nop_();
}
/*********************
****启动24C04*********
*******************/
void start_24C04()
{

SDA=1;
_nop_();
ATCLK=1;
_nop_();

SDA=0;
_nop_();
ATCLK=0;
_nop_();
}
/********************
*****停止24C04*******
*********************/
void stop_24C04()
{
SDA=0;
_nop_();

ATCLK=1;
_nop_();
SDA=1;
_nop_();

}
/*********************
****24C04应答*********
*******************/
void response()
{
unsigned char i;
ATCLK=1;
_nop_();
while((SDA==1)&&(i<250))i++;
ATCLK=0;
_nop_();
}
/********************
*****读取24C04一个字节**
**************************/
unsigned char read_byte()
{
SDA=1;
ATCLK=1;a7=SDA;ATCLK=0;
ATCLK=1;a6=SDA;ATCLK=0;
ATCLK=1;a5=SDA;ATCLK=0;
ATCLK=1;a4=SDA;ATCLK=0;
ATCLK=1;a3=SDA;ATCLK=0;
ATCLK=1;a2=SDA;ATCLK=0;
ATCLK=1;a1=SDA;ATCLK=0;
ATCLK=1;a0=SDA;ATCLK=0;
SDA=1;
ATCLK=0;
return ACC;
}
/*************************
**写入24C04一个字节******
*************************/
void write_byte(unsigned char addr)
{
ACC=addr;
SDA=a7;ATCLK=1;ATCLK=0;
SDA=a6;ATCLK=1;ATCLK=0;
SDA=a5;ATCLK=1;ATCLK=0;
SDA=a4;ATCLK=1;ATCLK=0;
SDA=a3;ATCLK=1;ATCLK=0;
SDA=a2;ATCLK=1;ATCLK=0;
SDA=a1;ATCLK=1;ATCLK=0;
SDA=a0;ATCLK=1;ATCLK=0;
SDA=1;
ATCLK=0;

}
/***********************
**写24C04的数据*******
*****************/
void write_24C04(unsigned char addr,unsigned char dat)
{
start_24C04();
write_byte(0xa0);
response();
write_byte(addr);
response();
write_byte(dat);
response();
stop_24C04();
}
/**********************
***读24C04的数据*******
*****************/
unsigned char read_24C04(unsigned char addr)
{
unsigned char t;
start_24C04();
write_byte(0xa0);
response();
write_byte(addr);
response();
start_24C04();
write_byte(0xa1);
response();
t=read_byte();
stop_24C04();
return t;
}