proteus仿真：I2c总线和EEPROM2404的读写

仿真电路图：

 

仿真程序：

#include

#include

#define uchar unsigned char

#define uint unsigned int

sbit SCL=P1^0;

sbit SDA=P1^1;

void delay(void)

{

_nop_();

_nop_();

_nop_();

_nop_();

}

void InitI2C(void)

{

SDA = 1;

SCL = 1;

}

void I2CStart(void)

{

SDA=1;

delay();

SCL=1;

delay();

SDA=0;

delay();

SCL=0;

}

void I2CStop(void)

{

SCL=0;

delay();

SDA=0;

delay();

SCL=1;

delay();

SDA=1;

delay();

}

void I2CSend(uchar byte)

{

uchar mask;

uchar i,j;

mask=0x80;

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

{

SCL=0;

delay();

if((mask & byte)==0)

{

SDA=0;

}

else

{

SDA=1;

}

mask>>=1;

delay();

SCL=1;

delay();

}

SCL=0;

SDA=1;

delay();

SCL=1;

j=SDA;

delay();

SCL=0;

}

void write_eeprom(uchar addr, uchar databyte)

{

I2CStart();

I2CSend(0xa0);

I2CSend(addr);

I2CSend(databyte);

I2CStop();

}

uchar I2CRead(void)

{

uchar byte;

uchar i;

byte = 0;

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

{

SCL = 0;

SDA = 1;

delay();

SCL = 1;

delay();

byte <<= 1;

if(SDA == 1)

{

byte |= 0x01;

}

delay();

}

SCL = 0;

SDA = 1;

delay();

SCL = 1;

delay();

SCL = 0;

return byte;

}

uchar read_eeprom(uchar addr)

{

uchar databyte;

I2CStart();

I2CSend(0xa0);

I2CSend(addr);

I2CStart();

I2CSend(0xa1);

databyte = I2CRead();

I2CStop();

return databyte;

}

main()

{

uchar addr=0x00,databyte=0xaa;

uchar c=0;

uint i;

InitI2C();

while(1)

{

write_eeprom(addr,databyte);

for(i = 0; i < 1000; i++)

{

delay();

}

c = read_eeprom(addr);

P2=c;

}

}