void IIC_Start(void)
{
SDA_OUT(); //sdaÏßÊä³ö
IIC_SDA=1;
IIC_SCL=1;
delay_us(5);
IIC_SDA=0;//START:when CLK is high,DATA change form high to low
delay_us(5);
IIC_SCL=0;
}
void IIC_Stop(void)
{
SDA_OUT();
IIC_SCL=0;
IIC_SDA=0;//STOP:when CLK is high DATA change form low to high
delay_us(5);
IIC_SCL=1;
IIC_SDA=1;
delay_us(5);
}
u8 IIC_Wait_Ack(void)
{
u16 ucErrTime=0;
SDA_IN(); //SDAÉèÖÃΪÊäÈë
IIC_SDA=1;
delay_us(2);
IIC_SCL=1;
delay_us(2);
while(READ_SDA)
{
ucErrTime++;
if(ucErrTime>200)
{
IIC_Stop();
return 1;
}
}
IIC_SCL=0;
return 0;
}
void IIC_Ack(void)
{
IIC_SCL=0;
SDA_OUT();
IIC_SDA=0;
delay_us(2);
IIC_SCL=1;
delay_us(2);
IIC_SCL=0;
}
void IIC_NAck(void)
{
IIC_SCL=0;
SDA_OUT();
IIC_SDA=1;
delay_us(2);
IIC_SCL=1;
delay_us(2);
IIC_SCL=0;
}
void IIC_Send_Byte(u8 txd)
{
u8 t;
SDA_OUT();
IIC_SCL=0;
for(t=0;t<8;t++)
{
if((((txd&0x80)>>7)&0x01)==0x01)
IIC_SDA=1;
else
IIC_SDA=0;
txd<<=1;
delay_us(5);
IIC_SCL=1;
delay_us(5);
IIC_SCL=0;
delay_us(5);
}
}
u8 IIC_Read_Byte()
{
unsigned char i,receive=0;
SDA_IN();//SDAÉèÖÃΪÊäÈë
for(i=0;i<8;i++ )
{
IIC_SCL=0;
delay_us(5);
IIC_SCL=1;
receive<<=1;
if(READ_SDA)receive++;
delay_us(5);
}
return receive;
}
u8 IIC_read_data()
{
uint8_t receive_data;
IIC_Start();
IIC_Send_Byte(0xa0);
IIC_Wai_Ack();
IIC_Send_Byte(0x0d);
IIC_Wait_Ack();
delay_us(50);
IIC_Start();
IIC_Send_Byte(0xa1);
IIC_Wait_Ack();
delay_us(40);
receive_data= IIC_Read_Byte();
IIC_Ack();
delay_us(40);
return receive_data;
}
频谱分析仪分析的图片
