I2C not getting started on TMS320F28033

Hi Joe, After you setup your I2C, you can try the following code to see if you pick up anything on the scope. Ive used this code to check bus activity and eeprom functionality.

// Capture bus and see SCL  on scope

// This code fills the first 64K of your eeprom with 0x55 and you should be able to see it on the scope.

// Once the Master captures the I2C bus, the SCL line is held LOW.

// No activity on the bus till it actually starts transmitting the start bit and address.

//Mode -Master Transmitter, Repeat mode, Single Start, !!!NO STOP BIT!!!, Master will hold bus indefinitely until a reset is issued or the loop hits

//FFFF after which a stop bit is issued

     I2caRegs.I2CSAR = 0x50;

     I2caRegs.I2CMDR.all = 0x66A0;

     while(I2caRegs.I2CSTR.bit.XRDY== 0){}; //Wait till registers can be accessed

    I2caRegs.I2CDXR = 0x00; //Send high byte of the eeprom write location

     while(I2caRegs.I2CSTR.bit.XRDY== 0){}; //Wait till registers can be accessed   

    I2caRegs.I2CDXR = 0x00; //Send low byte of the eeprom write location

    //NOTE : First two transmissions to an eeprom must always be the address you want to read/write to

      for(i = 0; i < 0xFFFF; i++)

      {

        while(I2caRegs.I2CSTR.bit.XRDY== 0){}; //Wait till registers can be accessed

        I2caRegs.I2CDXR = 0x55; //Write a bunch of 0x55's to the EEPROM starting at address location 0x0000 of the eeprom

      }

I2caRegs.I2CMDR.bit.STP = 1; //Send stop bit now

Thanks Vishal,

Just the kind of thing I was looking for to force some data!

Still no transitions on the clock line!

My setup is: SYSCLK 60 MHz, PSC = 6, CLKH = 10, CLKL = 5

I would think that once the address is set, then the write to the command register will immediately cause the Start bit and the first byte (A0) to go out.  I am triggering on a GPIO that I set at the start of your code, and unfortunately, the only pulse I see is my trigger going high!

I am going to try another board in the morning just in case, but since the other ports work, I don't think the board is the problem.

Joe

This is the setup I use

void vInitSystem()

{

//------------Setting up CLKs, PIE-------------------------------------------------

  InitSysCtrl();            //Start up the clocks, SysCtrl.c

  InitPieCtrl();            //Initialize the PIE

  InitPieVectTable();        //Copy PIE tables from the bootROM to the RA

  //------------Setting up the I2C-------------------------------------------------

  InitI2CGpio();            //Switch GPIO pins to be I2C pins

  I2caRegs.I2CPSC.all = 9; //PSC = (SYSCLKOUT/MODCLK)-1 ,@100MHz sysclk and 10MHz Modclk

  I2caRegs.I2CCLKL = 10;            // NOTE: must be non zero

  I2caRegs.I2CCLKH = 5;            // NOTE: must be non zero

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

}