//===============================
//define a bit_operation byte to use in shift operation
//use this mode can achieve high operation speed
unsigned char bdata bbyte;
sbit a0=bbyte^0;
sbit a1=bbyte^1;
sbit a2=bbyte^2;
sbit a3=bbyte^3;
sbit a4=bbyte^4;
sbit a5=bbyte^5;
sbit a6=bbyte^6;
sbit a7=bbyte^7;
//========================================
bit IFACK;//record the SDA state to confirn if ACK has happened
//bit NO_ACK;//no ack flag
//bit BUS_FAULT; //bus fault flag
//bit IIC_BUSY; //bus is busy flay
//========================================
//FUNCTION:ROUTES TO PROVIDE A START SIGNAL
void start(void)
{
SCL=0;_Nop();SDA=1;_Nop();SCL=1;_Nop();SDA=0;_Nop();SCL=0;_Nop();
}
//=======================================
//FUNCTION:ROUTES TO PROVIDE A STOP SIGNAL
void stop(void)
{
// SCL=0;_nop_();SDA=0;_nop_();SCL=1;_nop_();SDA=1;_nop_();SCL=0;_nop_();
SCL=0;_Nop();SDA=0;_Nop();SCL=1;_Nop();SDA=1;_Nop();SCL=0;_Nop();
}
//FUNCTION:ROUTES TO RELEASE THE SDA TO RECEIVE A ACK SIGNAL
//OR TO PROVIDE A NO_ACK SIGNAL
bit nack(void)
{
SCL=0;_nop_();SDA=1;_nop_();SCL=1;_nop_();IFACK=SDA;_nop_();SCL=0;_nop_(); return IFACK;
}
//=======================================================
//FUNCTION:THE IIC DEVICE SHIFT OUT A BYTE TO THE MASTER
unsigned char inbyte(void)
{
SDA=1;
SCL=1;_Nop();a7=SDA;SCL=0;_Nop();
SCL=1;_Nop();a6=SDA;SCL=0;_Nop();
SCL=1;_Nop();a5=SDA;SCL=0;_Nop();
SCL=1;_Nop();a4=SDA;SCL=0;_Nop();
SCL=1;_Nop();a3=SDA;SCL=0;_Nop();
SCL=1;_Nop();a2=SDA;SCL=0;_Nop();
SCL=1;_Nop();a1=SDA;SCL=0;_Nop();
SCL=1;_Nop();a0=SDA;SCL=0;_Nop();
return(bbyte);
}
//=======================================================
//FUNCTION:THE IIC DEVICE SHIFT IN A BYTE FROM THE MASTER
void outbyte(unsigned char outdata)
{
bbyte=outdata;
SDA=a7;_Nop();SCL=1;_Nop();SCL=0;_Nop();
SDA=a6;_Nop();SCL=1;_Nop();SCL=0;_Nop();
SDA=a5;_Nop();SCL=1;_Nop();SCL=0;_Nop();
SDA=a4;_Nop();SCL=1;_Nop();SCL=0;_Nop();
SDA=a3;_Nop();SCL=1;_Nop();SCL=0;_Nop();
SDA=a2;_Nop();SCL=1;_Nop();SCL=0;_Nop();
SDA=a1;_Nop();SCL=1;_Nop();SCL=0;_Nop();
SDA=a0;_Nop();SCL=1;_Nop();SCL=0;_Nop();
nack();
}
//======================================================
//FUNCTION:BYTE WRITE.
// 'add' THE WRITE ADDRESS,
// 'wbyte' THE DATA WANT TO WRITE
void writebyte(unsigned char add,unsigned char wbyte)
{
start();
outbyte(IIC_WRITER);
nack();
outbyte(add);
nack();
outbyte(wbyte);
nack();
stop();
}
//=====================================================
//FUNCTION:RANDOM READ.'add' IS THE ADDRESS WANT TO READ
unsigned char readbyte (unsigned char add)
{
unsigned char temp;
start();
outbyte(IIC_WRITER);
nack();
outbyte(add);
nack();
start();
outbyte(IIC_READ);
nack();
temp=inbyte();
nack();
stop();
return(temp);
}
