LAUNCHXL-F28069M: request by I2C to Gyro sensor - I2CDRR never ready to be read

Part Number: LAUNCHXL-F28069M
Other Parts Discussed in Thread: MOTORWARE

Hi,

I'm using gyro sensor MPU-6050 https://www.invensense.com/wp-content/uploads/2015/02/MPU-6000-Register-Map1.pdf

In my code I try to request data of gyro readings at 0x3B, and 0x3C registers, but program always stuck in line:

            while(I2caRegs.I2CSTR.bit.RRDY == 0){};     //I2CDRR not ready to read?

It means data has not been copied from I2CRSR to I2CDRR, but I dont have idea why.

Could you check my code please?

#include "DSP28x_Project.h"
#include <stdio.h>


Uint16 PassCount;
Uint16 FailCount;
Uint16 Data[]={0x6B,0x3B};
Uint16 RxdData[10];


void main(void)
{
    // Step 1. Initialize System Control:
    // PLL, WatchDog, enable Peripheral Clocks
    // This example function is found in the F2806x_SysCtrl.c file.
    //
    InitSysCtrl();

    //
    // Setup only the GP I/O only for I2C functionality
    //
    InitI2CGpio();

    //
    // Step 3. Clear all interrupts and initialize PIE vector table:
    // Disable CPU interrupts
    //
    DINT;

    //
    // Initialize PIE control registers to their default state.
    // The default state is all PIE interrupts disabled and flags
    // are cleared.
    // This function is found in the F2806x_PieCtrl.c file.
    //
    InitPieCtrl();

    //
    // Disable CPU interrupts and clear all CPU interrupt flags
    //
    IER = 0x0000;
    IFR = 0x0000;

    //
    // Initialize the PIE vector table with pointers to the shell Interrupt
    // Service Routines (ISR).
    // This will populate the entire table, even if the interrupt
    // is not used in this example.  This is useful for debug purposes.
    // The shell ISR routines are found in F2806x_DefaultIsr.c.
    // This function is found in F2806x_PieVect.c.
    //
    InitPieVectTable();


    PassCount = 0;
    FailCount = 0;

    //
    // Enable interrupts required for this example
    //

    //
    // Enable I2C interrupt 1 in the PIE: Group 8 interrupt 1
    //
    PieCtrlRegs.PIEIER8.bit.INTx1 = 1;

    //
    // Enable CPU INT8 which is connected to PIE group 8
    //
    IER |= M_INT8;
    EINT;

	
	
    //////////////////////////
    // Write data to EEPROM //
    //////////////////////////

    I2caRegs.I2CSAR = 0x68;            				//Set slave address
    I2caRegs.I2CCNT = 2;          					//Set count to 5 characters plus 2 address bytes
    I2caRegs.I2CDXR = 0x6B;							//register where i will write 0x40 (reset)
    I2caRegs.I2CMDR.bit.TRX = 1;               		//Set to Transmit mode
    I2caRegs.I2CMDR.bit.MST = 1;          	     	//Set to Master mode
    I2caRegs.I2CMDR.bit.FREE = 1;           	  	//Run in FREE mode
    I2caRegs.I2CMDR.bit.STP = 1;            	    //Stop when internal counter becomes 0
    I2caRegs.I2CMDR.bit.STT = 1;           	     	//Send the start bit, transmission will follow

    while(I2caRegs.I2CSTR.bit.XRDY == 0){};     	//Do nothing till data is shifted out
    I2caRegs.I2CDXR = 0x40;

    for(i = 0; i < 3; i++){
        RxdData[i] = 0x00;
    }

    for(;;)
    {

		//////////////////////////
		// Read data from EEPROM//
		//////////////////////////
		
        //while(I2caRegs.I2CSTR.bit.XRDY == 0){};      //Do nothing till data is shifted out
        I2caRegs.I2CSAR = 0x68;                      //Set slave address
        I2caRegs.I2CCNT = 1;                         //Set count to 2 address bytes
        I2caRegs.I2CDXR = 0x3B;                      //Send high address of register to read
        I2caRegs.I2CMDR.bit.TRX = 1;                 //Set to Transmit mode
        I2caRegs.I2CMDR.bit.MST = 1;                 //Set to Master mode
        I2caRegs.I2CMDR.bit.FREE = 1;                //Run in FREE mode
        I2caRegs.I2CMDR.bit.STP = 0;                 //Dont release the bus after Tx
        I2caRegs.I2CMDR.bit.STT = 1;                 //Send the start bit, transmission will follow

        while(I2caRegs.I2CSTR.bit.XRDY == 0){};      //Do nothing till data is shifted out
        //I2caRegs.I2CDXR = 0x3B;                      //Send low address of register to read
        //while(I2caRegs.I2CSTR.bit.XRDY == 0){};      //Do nothing till data is shifted out
        I2caRegs.I2CCNT = 2;                         //read 5 bytes from eeprom
        I2caRegs.I2CMDR.bit.TRX = 0;                 //Set to Recieve mode
        I2caRegs.I2CMDR.bit.MST = 1;                 //Set to Master mode
        I2caRegs.I2CMDR.bit.FREE = 1;                //Run in FREE mode
        I2caRegs.I2CMDR.bit.STP = 1;                 //Stop when internal counter becomes 0
        I2caRegs.I2CMDR.bit.STT = 1;                 //Repeated start, Reception will follow
		
        for(i = 0; i < 2; i++){
             while(I2caRegs.I2CSTR.bit.RRDY == 0){};     //I2CDRR not ready to read?   program stuck here in endless loop
             RxdData[i] = I2caRegs.I2CDRR;
             PassCount++;
        }


    }
}