感觉AVR的IO模拟I2C和51模拟还是有区别的，下面是AVR和51的模拟I2C的例子。小弟现在有点迷惑，那位达人能解释一下？
/***********************AVR
unsigned char I2C_Read(unsigned char bEnd)
{
unsigned char i,mb;
Set_SDA; //release sda line
mb=0;
for(i=0;i<8;i++)
{
mb=mb<<1;
I2C_Delay();
Set_SCL;
I2C_Delay();
if( SDA_High ) mb++;
I2C_Delay();
Cls_SCL;
if(i!=7) I2C_Delay();
}
if( bEnd ) Set_SDA; //end read
else Cls_SDA; //ack
I2C_Delay();
Set_SCL;
I2C_Delay();
Cls_SCL;
I2C_Delay();
Set_SDA;
return mb;
}
////////////////////////51
unsigned char I2C_Read()
{
unsigned char dat;
unsigned char t = 8;
I2C_SDA = 1; //在读取数据之前，要把SDA拉高，使之处于输入状态
do
{
I2C_SCL = 1; I2C_Delay();
dat <<= 1;
if ( I2C_SDA ) dat++;
I2C_SCL = 0; I2C_Delay();
} while ( --t != 0 );
return dat;
}
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楼主
