CCS/TMS320F28027: CCS/TMS320F28027: I2C EEPROM

Hi Dave,

You would need to edit the example program. I'd suggest looking at the AT24C08 datasheet as it has a slightly different protocol than the 24WC256 for reads/writes.

When setting up a read/write for the 24WC256 you send two 8-bit address words (HIGH and LOW addresses) before actually sending or receiving data:

    //
    // Setup number of bytes to send MsgBuffer + Address
    //
    I2caRegs.I2CCNT = msg->NumOfBytes+2;

    //
    // Setup data to send
    //
    I2caRegs.I2CDXR = msg->MemoryHighAddr;
    I2caRegs.I2CDXR = msg->MemoryLowAddr;

    for (i=0; i<msg->NumOfBytes; i++)
    {
        I2caRegs.I2CDXR = *(msg->MsgBuffer+i);
    }

For your AT24C08, if you look at its datasheet, reads/writes only use one 8-bit address word instead of two. There may be some other caveats as well, that's just what I noticed looking at the DS.

Best,

Kevin

Dear Kevin thanks for suggestion.

eventually I could write and read 2byte to/from EEPROM by removing  

MemoryHighAddr form I2CA_WriteData(struct I2CMSG *msg) and Uint16 I2CA_ReadData(struct I2CMSG *msg) functions and changing  I2caRegs.I2CCNT register. 

for I2CA_WriteData function I2caRegs.I2CCNT register is equal 3(1 address ,2 data) and for I2CA_ReadData function I2caRegs.I2CCNT register is equal 1(1 address ).

So ,now I need to store 25 word into EEPROM ,and read them ,so to continue to work I removed for(;;) form pass and fail functions.

to program be in main loop at all time .

void pass()
{
 //   asm("   ESTOP0");
 //   for(;;);
}

void fail()
{
 //   asm("   ESTOP0");
 //  for(;;);
}

and also for storing 25 word I wrote

		     //cnt initialize cnt=0
                     cnt++;
		     I2cMsgOut1.MsgBuffer[0]=cnt;
		     cnt++;
		     I2cMsgOut1.MsgBuffer[1]=cnt;
                     
                     //adrs initialize adrs=0
		     adrs++;
		     I2cMsgOut1.MemoryLowAddr = adrs;
           
                     if(adrs==25) {for(;;);}

		     CurrentMsgPtr = &I2cMsgOut1;

		     I2cMsgOut1.MsgStatus == I2C_MSGSTAT_SEND_WITHSTOP;

so by doing that we expect to store 25 word 

 but sadly none of datas was stored.

I got confused please help me to solve my problem ,

  // Application loop
   for(;;)
   {


             // for making delay on every write/ read
	     for(j=0;j<10000;j++)

		     I2cMsgOut1.MsgStatus=I2C_MSGSTAT_SEND_WITHSTOP;
		     I2cMsgOut1.SlaveAddress=I2C_SLAVE_ADDR;
		     I2cMsgOut1.NumOfBytes=I2C_NUMBYTES;
		     I2cMsgOut1.MemoryHighAddr=I2C_EEPROM_HIGH_ADDR;

		     cnt++;
		     I2cMsgOut1.MsgBuffer[0]=cnt;
		     cnt++;
		     I2cMsgOut1.MsgBuffer[1]=cnt;
		     adrs++;
		     I2cMsgOut1.MemoryLowAddr = adrs;

		     CurrentMsgPtr = &I2cMsgOut1;

		     I2cMsgOut1.MsgStatus == I2C_MSGSTAT_SEND_WITHSTOP;


      //////////////////////////////////
      // Write data to EEPROM section //
      //////////////////////////////////
      // Check the outgoing message to see if it should be sent.
      // In this example it is initialized to send with a stop bit.
      if(I2cMsgOut1.MsgStatus == I2C_MSGSTAT_SEND_WITHSTOP)
      {
         Error = I2CA_WriteData(&I2cMsgOut1);
         // If communication is correctly initiated, set msg status to busy
         // and update CurrentMsgPtr for the interrupt service routine.
         // Otherwise, do nothing and try again next loop. Once message is
         // initiated, the I2C interrupts will handle the rest. Search for
         // ICINTR1A_ISR in the i2c_eeprom_isr.c file.
         if (Error == I2C_SUCCESS)
         {
            CurrentMsgPtr = &I2cMsgOut1;
            I2cMsgOut1.MsgStatus = I2C_MSGSTAT_WRITE_BUSY;
         }
      }  // end of write section

// for making delay on every write/ read
for(j=0;j<100000;j++){}

 
    I2cMsgIn1.MsgStatus=I2C_MSGSTAT_SEND_NOSTOP;
     I2cMsgIn1.SlaveAddress=I2C_SLAVE_ADDR;
     I2cMsgIn1.NumOfBytes=I2C_NUMBYTES;
    I2cMsgIn1.MemoryHighAddr=I2C_EEPROM_HIGH_ADDR;

   //It will read the previous Data from EEPROM
    I2cMsgIn1.MemoryLowAddr = adrs-1;

      ///////////////////////////////////
      // Read data from EEPROM section //
      ///////////////////////////////////
      // Check outgoing message status. Bypass read section if status is
      // not inactive.
      if (I2cMsgOut1.MsgStatus == I2C_MSGSTAT_INACTIVE)
      {
         // Check incoming message status.
         if(I2cMsgIn1.MsgStatus == I2C_MSGSTAT_SEND_NOSTOP)
         {
            // EEPROM address setup portion
            while(I2CA_ReadData(&I2cMsgIn1) != I2C_SUCCESS)
            {
               // Maybe setup an attempt counter to break an infinite while
               // loop. The EEPROM will send back a NACK while it is performing
               // a write operation. Even though the write communique is
               // complete at this point, the EEPROM could still be busy
               // programming the data. Therefore, multiple attempts are
               // necessary.
            }
            // Update current message pointer and message status
            CurrentMsgPtr = &I2cMsgIn1;
            I2cMsgIn1.MsgStatus = I2C_MSGSTAT_SEND_NOSTOP_BUSY;
         }

         // Once message has progressed past setting up the internal address
         // of the EEPROM, send a restart to read the data bytes from the
         // EEPROM. Complete the communique with a stop bit. MsgStatus is
         // updated in the interrupt service routine.
         else if(I2cMsgIn1.MsgStatus == I2C_MSGSTAT_RESTART)
         {
            // Read data portion
            while(I2CA_ReadData(&I2cMsgIn1) != I2C_SUCCESS)
            {
               // Maybe setup an attempt counter to break an infinite while
               // loop.
            }
            // Update current message pointer and message status
            CurrentMsgPtr = &I2cMsgIn1;
            I2cMsgIn1.MsgStatus = I2C_MSGSTAT_READ_BUSY;
         }
       }  // end of read section

   }   // end of for(;;)
}   // end of main

 I need to store 25 word into EEPROM ,and read them, I really need your help to solve my problem .

Regards.


Dave.

thanks dear Kevin

I am going to see e2e.ti.com/.../2627724

then I will tell you if my issue is solved or not .

regards

Dave.