avr单片机IIc总线编程

/*=========================================

IicWrite(uchar ad,uchar da)：ad=寄存器地址,da=数据;
IicRead(uchar ad): ad=寄存器地址
=========================================*/
void IicWrite(uchar ad,uchar da)
{
IIC_Start();
IIC_Wait();
TWDR=0xA2;//从机地址
IIC_Ack();
IIC_Wait();
TWDR=ad;
IIC_Ack();
IIC_Wait();
TWDR=da;
IIC_Ack();
IIC_Wait();
IIC_Stop();
}
uchar IicRead(uchar ad)
{
unsigned char data;
IIC_Start();
IIC_Wait();
TWDR = 0xA2;//从机地址
IIC_Ack();
IIC_Wait();
TWDR = ad;
IIC_Ack();
IIC_Wait();

IIC_Start();
IIC_Wait();
TWDR = 0xA3;
IIC_Ack();
IIC_Wait();
IIC_NoneAck();
IIC_Wait();
data=TWDR;
IIC_Stop();
return data;
}

单片机工作在IIC工作在主机方式下,对从机读取数据及写入数据.已经调试通过.希望大家能够补充完善.