TMS320F28069: I2C Communiciation with MCP9808

Part Number:TMS320F28069

Hi,

I am trying to read temperature data from MCP9808 via I2C of F28069 MCU. But I could not. Please find the code below. Do you have any suggestion?

MCP9808

// I2C GPIO Configuration
/* Enable internal pull-up for the selected pins */
GpioCtrlRegs.GPBPUD.bit.GPIO32 = 0;    // Enable pull-up for GPIO32 (SDAA)
GpioCtrlRegs.GPBPUD.bit.GPIO33 = 0;    // Enable pull-up for GPIO33 (SCLA)
/* Set qualification for selected pins to asynch only */
GpioCtrlRegs.GPBQSEL1.bit.GPIO32 = 3;  // Asynch input GPIO32 (SDAA)
GpioCtrlRegs.GPBQSEL1.bit.GPIO33 = 3;  // Asynch input GPIO33 (SCLA)
/* Configure I2C pins using GPIO regs*/
GpioCtrlRegs.GPBMUX1.bit.GPIO32 = 1;   // Configure GPIO32 for SDAA operation
GpioCtrlRegs.GPBMUX1.bit.GPIO33 = 1;   // Configure GPIO33 for SCLA operation

void InitI2C()
{
   // Initialize I2C

	I2caRegs.I2CMDR.bit.IRS = 0;
	I2caRegs.I2CPSC.all = 8;		// Prescaler - need 7-12 Mhz on module clk
	I2caRegs.I2CCLKL = 10;			// NOTE: must be non zero
	I2caRegs.I2CCLKH = 5;			// NOTE: must be non zero
	I2caRegs.I2CIER.all = 0x24;		// Enable SCD & ARDY interrupts

	I2caRegs.I2CMDR.all = 0x0020;	// Take I2C out of reset
					// Stop I2C when suspended

	I2caRegs.I2CFFTX.all = 0x6000;	// Enable FIFO mode and TXFIFO
	I2caRegs.I2CFFRX.all = 0x2040;	// Enable RXFIFO, clear RXFFINT,

	return;
}

long GetTemperature(void)
{
	long Temperature;
	long TempUpperByte;
	long TempLowerByte;

	I2caRegs.I2CMDR.bit.IRS = 1;                // reset I2C

	// Make sure I2C is not busy and has stopped
	while (I2caRegs.I2CSTR.bit.BB == 1);        // busy loop
	I2caRegs.I2CSTR.bit.SCD = 1;                // Clear the SCD bit (stop condition bit)
	while(I2caRegs.I2CMDR.bit.STP == 1);        // stop bit loop

	//I2caRegs.I2CMDR.all = 0x6620;                 // start, stop, no rm, reset i2c  01101110 00100000
	I2caRegs.I2CMDR.bit.NACKMOD = 0;            // NACK mode bit
	I2caRegs.I2CMDR.bit.FREE = 1;               // Run free I2C when suspended
	I2caRegs.I2CMDR.bit.STT = 1;                // START condition bit
	I2caRegs.I2CMDR.bit.STP = 0;                // STOP condition bit
	I2caRegs.I2CMDR.bit.MST = 1;                // Master mode
	I2caRegs.I2CMDR.bit.TRX = 1;                // Transmitter mode
	I2caRegs.I2CMDR.bit.XA = 0;                 // 7-bit addressing mode
	I2caRegs.I2CMDR.bit.RM = 0;                 // Nonrepeat mode
	I2caRegs.I2CMDR.bit.DLB = 0;                // Digital loopback mode is disabled
	I2caRegs.I2CMDR.bit.IRS = 1;                // The I2C module is enabled
	I2caRegs.I2CMDR.bit.STB = 0;                // The I2C module is not in the START byte mode
	I2caRegs.I2CMDR.bit.FDF = 1;                // Free data format mode is disabled
	I2caRegs.I2CMDR.bit.BC = 0;                 // 8 bits per data byte

	while(I2caRegs.I2CSTR.bit.XRDY == 0);       // Do nothing till bus is free
	I2caRegs.I2CMDR.bit.STT = 1;                // START condition bit
	I2caRegs.I2CDXR = 0x32;
	while(I2caRegs.I2CSTR.bit.NACK == 1);
	I2caRegs.I2CDXR = 0x05;                      // register address of the sensor (1 byte)
	while(I2caRegs.I2CSTR.bit.NACK == 1);
	I2caRegs.I2CMDR.bit.STT = 1;                // START condition bit
	I2caRegs.I2CDXR = 0x33;
	while(I2caRegs.I2CSTR.bit.NACK == 1);
	TempUpperByte = I2caRegs.I2CDRR;
	while(I2caRegs.I2CSTR.bit.NACK == 1);
	I2caRegs.I2CMDR.bit.NACKMOD == 1;
	TempLowerByte = I2caRegs.I2CDRR;
	while(I2caRegs.I2CSTR.bit.NACK == 0);
	I2caRegs.I2CMDR.bit.STP = 1;

	Temperature = (TempUpperByte * 16 + TempLowerByte / 16);

	return Temperature;
}