1.線接對(duì)了沒有；2.速率是否符合要求；3.給你發(fā)一下我的這個(gè)發(fā)送函數(shù)你對(duì)照著看看吧
bit I2C_Write(unsigned char dat)
{
    bit ack;
    unsigned char pos;
   
    for (pos=0x80; pos; pos>>=1)
    {
        if (dat & pos)
            I2C_SDA = 1;
        else
            I2C_SDA = 0;
        I2C_Delay(0);
        I2C_SCL = 1;
        I2C_Delay(1);
        I2C_SCL = 0;
        I2C_Delay(0);
    }
    I2C_SDA = 1;  //釋放SDA
    I2C_Delay(0);
    I2C_SCL = 1;
    I2C_Delay(0);
    ack = I2C_SDA;  //
    I2C_Delay(0);
    I2C_SCL = 0;
    I2C_Delay(1);

    return !ack;
}