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Mplabx -I2C-Temperature sensor TMP102 2015-07-09

i got ack from the slave bt its not receivng right value of temperature.its receiving continously FF
here is the code.....i need help...

int main()

{
I2C1CONbits.GCEN = 1;
TRISA=0;
// SDA=0;
// SCL=0;
char y;

// unsigned int data2,data1,data3;
unsigned char data1,data2,data3;
int data4,data5,data6;
//while(1){
InitI2C();
//while(1){
I2C_Start();
// AckI2C1();// send start sequence
y = I2C_Write_Byte(0x48);
y = I2C_Write_Byte(0x00);
//y = I2C_Write_Byte(0x06);

// I2C1CONbits.RCEN =1;
// while(I2C1CONbits.RCEN==0);
I2C_ReStart();

y = I2C_Write_Byte(0x49);
//astergetsI2C1(0x04, 0x10, 0x03);
//data1= MastergetsI2C1(0x02,0x10,0x02);
while(1){
data1 = I2C_Read_Byte(0);
data2 = I2C_Read_Byte(1);

data3=data2>>4;
data4=(data1<<4)&0xff0;
data5=data3|data4;
data6=data5*0.0625;
PORTA=data6;
LATA=data6;
__delay_ms(7000);
}
I2C_Stop();

return(EXIT_SUCCESS);

}

void InitI2C(void)
{
SDA_dir = 0; // Data pin direction
SCL_dir = 0; // clock pin direction
SCL= 1;
SDA=1;
int temp;
TRISA = 0x00;
OSCCON = 0x7701;
CLKDIV = 0x0000;
OSCTUN = 0x0000;
I2C1ADD = 0x0027;
// slave device address
I2C1BRG = 0x0004;

I2C1CONbits.I2CEN = 0; // Disable I2C Mode
I2C1CONbits.DISSLW =0; // Disable slew rate control
IFS1bits.MI2C1IF = 0; // Clear Interrupt
I2C1CONbits.I2CEN = 1; // Enable I2C Mode

temp = I2C1RCV; // read buffer to clear buffer full
I2C_Stop(); // set bus to idle

}

void I2C_Start(void)
{

int x = 0;
I2C1CONbits.ACKDT = 0; //Reset any previous Ack
__delay_us(10);
I2C1CONbits.SEN = 1; //Initiate Start condition
Nop();

//the hardware will automatically clear Start Bit
//wait for automatic clear before proceding
while (I2C1CONbits.SEN)
{
__delay_us(1);
x++;
if (x > 20)
break;
}
__delay_us(2);

}

void I2C_Stop(void)
{

int x = 0;

//initiate stop bit
I2C1CONbits.PEN = 1;

//wait for hardware clear of stop bit
while (I2C1CONbits.PEN)
{
__delay_us(1);
x ++;
if (x > 20)
break;
}
//I2C1CONbits.RCEN = 0;
IFS1bits.MI2C1IF = 0; // Clear Interrupt
I2C1STATbits.IWCOL = 0;
I2C1STATbits.BCL = 0;
__delay_us(10);

}

void I2C_ReStart(void)
{

int x = 0;

I2C1CONbits.RSEN = 1; //Initiate restart condition
Nop();

//the hardware will automatically clear restart bit
//wait for automatic clear before proceding
while (I2C1CONbits.RSEN)
{
__delay_us(1);
x++;
if (x > 20)
break;
}

__delay_us(2);

}

//void I2C_Send_ACK(void)
//{
// I2C1CONbits.ACKDT = 0;
// I2C1CONbits.ACKEN = 1;
// while(I2C1CONbits.ACKEN);
//}
//
//void I2C_Send_NACK(void)
//{
// I2C1CONbits.ACKDT = 1;
// I2C1CONbits.ACKEN = 1;
// while(I2C1CONbits.ACKEN);
//}

unsigned char I2C_Write_Byte(unsigned char data)
{

int i;
while(I2C1STATbits.BCL ==1);
while (I2C1STATbits.TBF==1){}
// Clear Interrupt

I2C1TRN = data; // load the outgoing data byte
while(I2C1STATbits.IWCOL==1);
while( IFS1bits.MI2C1IF == 0)
IFS1bits.MI2C1IF = 0;
// wait for transmission
for (i=0; i<500; i++)
{
if (!I2C1STATbits.TRSTAT) break;
__delay_us(1);
}
if (i == 500)
{
return(1);
}

// Check for NO_ACK from slave, abort if not found
if (I2C1STATbits.ACKSTAT == 1)
{
//I2C_Stop();
return(1);
}
__delay_us(2);

return(0);

}

//function reads data, returns the read data, with ack

unsigned char I2C_Read_Byte( char ack)
{
//int j;
I2C1CONbits.RCEN = 1;
while(I2C1CONbits.RCEN==0);
// I2C1STATbits.I2COV = 0;
// j=I2C1RCV<<8;
// AckI2C1();
int i,data = 0;
// I2C1CONbits.RCEN = 1;
data= I2C1RCV;


while (I2C1STATbits.RBF != 1);

data= I2C1RCV;
__delay_us(300);
data = I2C1RCV ;


I2C1CONbits.ACKDT = 1;
I2C1CONbits.ACKEN = 1;




// set I2C module to receive
//I2C1CONbits.RCEN = 1;
data = I2C1RCV ;
//if no response, break

__delay_us(2);
//get data from I2CRCV register
data = I2C1RCV;
if(ack==0){
I2C1CONbits.ACKDT = 0;
}
else{
I2C1CONbits.ACKDT = 1;
}
// set ACK to high
I2C1CONbits.ACKEN = 1;

//wait before exiting
__delay_us(10);

return data;
}
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NIKITA PATEL
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