(3)读写单个字节的段

u8 I2C_Send_Byte(u8 bytedata)

{

u8 i,ack;

I2C_SDA_Mode(1);  //SDA输出

I2C_SCL_OUTP();

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

{

if (bytedata & 0x80)

{

I2C_SDA_Output(1);

}

else

{

I2C_SDA_Output(0);

}

bytedata <<= 1;

I2C_SCL_Output(1);

udelay(3);

I2C_SCL_Output(0);

udelay(1);

}

I2C_SDA_Output(1);  //release

udelay(3);

I2C_SDA_Mode(0);  //设定SDA输入

I2C_SCL_Output(1);

udelay(3);

ack = I2C_SDA_Read();   //读应答

I2C_SDA_Mode(1);

I2C_SCL_Output(0);

udelay(3);

return ack;

}

u8 I2C_Receive_Byte(void)

{

u8 i;

u8 bytedata = 0x00;

u8 temp;

I2C_SDA_Mode(0);

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

{

I2C_SCL_Output(1);

udelay(3);

bytedata <<= 1;

temp = I2C_SDA_Read();

printk("reda SDA'value is:%d\n",temp);

if (temp)

bytedata |= 0x01;

printk("  bytedata is:%x\n",bytedata);

I2C_SCL_Output(0);

udelay(1);

}

I2C_SDA_Mode(1);

return bytedata;

}

(4)读写单个字节的I2C应用函数

u8 I2C_Byte_Write(u8 device_ID,u8 address,u8 bytedata)

{

u8 ack;

printk("device_ID is:%x\n",device_ID);

printk("address is:%x\n",address);

printk("date is:%x\n",bytedata);

I2C_Start();

ack=I2C_Send_Byte(device_ID);

printk("ack is:%d\n",ack);

if(ack)

I2C_Stop();

I2C_Send_Byte(address);

I2C_Send_Byte(bytedata);

I2C_Stop();

I2C_Wait();

return 0;

}

u8 I2C_Byte_Read(u8 device_ID,u8 address)

{

u8 bytedata;

I2C_Start();

I2C_Send_Byte(device_ID);

I2C_Send_Byte(address);

I2C_Start();

I2C_Send_Byte(device_ID+1);

bytedata = I2C_Receive_Byte();  //读单个字节，不需要再发应答

I2C_Stop();

return bytedata;

}

(5)类似可以完成读写多个字节的函数，暂不补充。