I2C communication problems with TMS320F28035

Hi Chandini,

Are you following this procedure?

Regards,

Gautam

Gowtham

Am following the same way i verified BB bit is 0 before proceding. my problem is no activity on SCL and SDA.

as soon as the code is run, the SCL goes low and stays low. It's not pulsing at all. I'm not seeing SDATA doing any activity either. It stays as it is, high.

if i check this after 1st data tranfer, execution stops at below line 

while(I2caRegs.I2CMDR.bit.STP == 1) { //// wait until the STP bit is cleared from any previous master communication
}

whatever my big question is why am not getting any signals on SCL and SDA

Someone can help me please

Hello,

I want to confirm:

- How do you set GPIO28 and GPIO29?

- What docking station/kit that you use for TMS320F28035? Is it TI board or custom board?

- Please make sure the hardware connection of your sensor (MPU9150) is correct (typically need pull up).

Best regards,

Maria

Also you can refer to the attached i2c.c file in this thread

http://e2e.ti.com/support/microcontrollers/c2000/f/171/p/266550/931938.aspx#931938

Best regards,

Maria

Maria

am using custom board not TI board ..my hardware connection is proper i think there is internal pull up resistor on SCL and SDA [in MPU9150]. and value of pull up is 10k

ok i ll go through that file and get back to you

-am setting GPIO28 and GPIO29 as follows

void InitI2CGpio()
{

EALLOW;

GpioCtrlRegs.GPAPUD.bit.GPIO28 = 0;
GpioCtrlRegs.GPAPUD.bit.GPIO29 = 0;

GpioCtrlRegs.GPAQSEL2.bit.GPIO28 = 3;

GpioCtrlRegs.GPAQSEL2.bit.GPIO29 = 3;

GpioCtrlRegs.GPAMUX2.bit.GPIO28 = 2; // // 0=GPIO, 1=SCIRX-A, 2=I2CSDA-A, 3=TZ2
GpioCtrlRegs.GPAMUX2.bit.GPIO29 = 2; // // 0=GPIO, 1=SCIRX-A, 2=I2CSDA-A, 3=TZ2

EDIS;
}

Are you using ControlSuite as your project template or are you making it from beginning?

I just want to make sure that GPIO28 and GPIO29 are not set anywhere else. And I want to make sure your GPIO28 and GPIO29 pins don't have contention with SCI/ any other connection in your hardware.

Best regards,

Maria

Maria

new project  ..am sure GPIO28 and GPIO29 are not set anywhere els..bcz this project is only for I2c with MPU9150.

how cn i attach my project code here.??

chandini raj said:

the SCL goes low and stays low.

Did you already enable the I2C clock ( SysCtrlRegs.PCLKCR0.bit.I2CAENCLK = 1;)?

chandini raj said:

how cn i attach my project code here.??

Just paste your code here. Or insert the file using the clip icon in the editor.

zip file of my project is attached here..

--am already enabled the I2C clock ( SysCtrlRegs.PCLKCR0.bit.I2CAENCLK = 1) 

#include "DSP28x_Project.h"     // Device Headerfile and Examples Include File
#include "Piccolo_Mpu9150.h"

void   I2CA_Init(void);

unsigned char accelerometer[6],gyroscope[6];


void main(void)
{

// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2803x_SysCtrl.c file.
   InitSysCtrl();

// Step 2. Initalize GPIO:
// This example function is found in the DSP2803x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio();
// 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 DSP2803x_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 DSP2803x_DefaultIsr.c.
// This function is found in DSP2803x_PieVect.c.
   InitPieVectTable();


    I2CA_Init();

   initSensorWithPiccolo();
   
   EINT;   // Enable Global interrupt INTM
   ERTM;   // Enable Global realtime interrupt DBGM

   while(1)
   	{
   		accelerometer[0]=readRegisterWithPiccolo(ACCEL_XOUT_H);
//   		accelerometer[1]=readRegisterWithPiccolo(ACCEL_XOUT_L);
//   		accelerometer[2]=readRegisterWithPiccolo(ACCEL_YOUT_H);
//   		accelerometer[3]=readRegisterWithPiccolo(ACCEL_YOUT_L);
//   		accelerometer[4]=readRegisterWithPiccolo(ACCEL_ZOUT_H);
//   		accelerometer[5]=readRegisterWithPiccolo(ACCEL_ZOUT_L);
//
//   		gyroscope[0] 	=readRegisterWithPiccolo(GYRO_XOUT_H);
//   		gyroscope[1]	=readRegisterWithPiccolo(GYRO_XOUT_L);
//   		gyroscope[2]	=readRegisterWithPiccolo(GYRO_YOUT_H);
//   		gyroscope[3]	=readRegisterWithPiccolo(GYRO_YOUT_L);
//   		gyroscope[4]	=readRegisterWithPiccolo(GYRO_ZOUT_H);
//   		gyroscope[5]	=readRegisterWithPiccolo(GYRO_ZOUT_L);
   	}

}// end of main

void I2CA_Init(void)
{
	I2caRegs.I2CMDR.all = 0x0000;
   // Initialize I2C
   I2caRegs.I2CSAR = 0x68;		// MEMS address

   I2caRegs.I2CPSC.all = 6;		    // 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 = 0x3E;		// 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;
}
//===========================================================================
// No more.
//===========================================================================

Can you try this main.c and let me know whether you get the pulse or not.

Maria

same thing as before ,no activity on SDA and SCL ..SCL goes low and stays low.

Then I want to know when you test this ControlSuite example (C:\ti\controlSUITE\device_support\f2803x\v127\DSP2803x_examples_ccsv5\i2c_eeprom), do you get any pulse?

Maria

ya already i tried using [C:\ti\controlSUITE\device_support\f2803x\v127\DSP2803x_examples_ccsv5\i2c_eeprom] controlsuit program ..if i simply run that program without connecting EEPROM am getting some signals on SDA and SCL . 

Maria

thanks again for your replay.. ya i tried with those files ..yes now am getting some signals on SCL and SDA lines

That's good as a start!

Then I hope you can continue modifying it for your application.

Good luck!

Best regards,

Maria

ya i ll take care from now on..good thing is that after uncommenting my initSensorWithPiccolo() in the main als am getting some signals on SDA and SCL lines

thanks a lot Maria

That's good. You're welcome!

Best regards,

Maria