TMS320F28035: Regarding SCI

Hi RK,

What's the doubt?

Regards,
Gautam

Hi,
I am referring to the Example code:

Example_2803xSci_FFDLB_int

I want to increase the Data Length size.
Here in the example code data array size is:2..

Suppose I want a data size of 5 , I am unable to get the Sdata & Rdata correctly.

Pls suggest me.

ramakrishna dutt said:

Suppose I want a data size of 5 , I am unable to get the Sdata & Rdata correctly.

Pls suggest me.

What changes did you do to the code for achieving the data size of 5?

For your understanding on my problem, Pleass find the atttached code as below: (Example Code Original)

 

At the bottom, I am giving the modified code, please suggest the improvements to be done.

//###########################################################################

//

//!  \addtogroup f2803x_example_list

//!  <h1>SCI Digital Loop Back with Interrupts(scia_loopback_interrupts)</h1>

//!

//!  This program uses the internal loop back test mode of the peripheral.

//!  Other then boot mode pin configuration, no other hardware configuration

//!  is required. Both interrupts and the SCI FIFOs are used.

//!

//!  A stream of data is sent and then compared to the received stream.

//!  The SCI-A sent data looks like this: \n

//!  00 01 \n

//!  01 02 \n

//!  02 03 \n

//!  .... \n

//!  FE FF \n

//!  FF 00 \n

//!  etc.. \n

//!  The pattern is repeated forever.

//!

//!  \b Watch \b Variables \n

//!  - \b sdataA , Data being sent

//!  - \b rdataA , Data received

//!  - \b rdata_pointA ,Keep track of where we are in the datastream.

//!    This is used to check the incoming data

//

//###########################################################################

// $TI Release: F2803x C/C++ Header Files and Peripheral Examples V127 $

// $Release Date: March 30, 2013 $

//###########################################################################

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

#define CPU_FREQ    60E6

#define LSPCLK_FREQ CPU_FREQ/4

#define SCI_FREQ    100E3

#define SCI_PRD     (LSPCLK_FREQ/(SCI_FREQ*8))-1

// Prototype statements for functions found within this file.

__interrupt void sciaTxFifoIsr(void);

__interrupt void sciaRxFifoIsr(void);

__interrupt void scibTxFifoIsr(void);

__interrupt void scibRxFifoIsr(void);

void scia_fifo_init(void);

void scib_fifo_init(void);

void error(void);

// Global variables

Uint16 sdataA[2];    // Send data for SCI-A

Uint16 rdataA[2];    // Received data for SCI-A

Uint16 rdata_pointA; // Used for checking the received data

void main(void)

{

  Uint16 i;

// 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 SCI-A and SCI-B functionality

// This function is found in DSP2803x_Sci.c

  InitSciGpio();

// 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();

// Interrupts that are used in this example are re-mapped to

// ISR functions found within this file.

  EALLOW;  // This is needed to write to EALLOW protected registers

  PieVectTable.SCIRXINTA = &sciaRxFifoIsr;

  PieVectTable.SCITXINTA = &sciaTxFifoIsr;

  EDIS;   // This is needed to disable write to EALLOW protected registers

// Step 4. Initialize all the Device Peripherals:

// This function is found in DSP2803x_InitPeripherals.c

// InitPeripherals(); // Not required for this example

  scia_fifo_init();  // Init SCI-A

// Step 5. User specific code, enable interrupts:

// Init send data.  After each transmission this data

// will be updated for the next transmission

  for(i = 0; i<2; i++)

  {

//      sdataA[i] = i;

  sdataA[0] = 54;

  sdataA[1] = 96;

  }

  rdata_pointA = sdataA[0];

// Enable interrupts required for this example

  PieCtrlRegs.PIECTRL.bit.ENPIE = 1;   // Enable the PIE block

  PieCtrlRegs.PIEIER9.bit.INTx1=1;     // PIE Group 9, INT1

  PieCtrlRegs.PIEIER9.bit.INTx2=1;     // PIE Group 9, INT2

  IER = 0x100; // Enable CPU INT

  EINT;

// Step 6. IDLE loop. Just sit and loop forever (optional):

   for(;;);

}

void error(void)

{

   __asm("     ESTOP0"); // Test failed!! Stop!

   for (;;);

}

__interrupt void sciaTxFifoIsr(void)

{

   Uint16 i;

   for(i=0; i< 2; i++)

   {

      SciaRegs.SCITXBUF=sdataA[i];     // Send data

   }

   for(i=0; i< 2; i++)                 //Increment send data for next cycle

   {

      sdataA[i] = (sdataA[i]+1) & 0x00FF;

   }

   SciaRegs.SCIFFTX.bit.TXFFINTCLR=1;  // Clear SCI Interrupt flag

   PieCtrlRegs.PIEACK.all|=0x100;      // Issue PIE ACK

}

__interrupt void sciaRxFifoIsr(void)

{

   Uint16 i;

   for(i=0;i<2;i++)

   {

      rdataA[i]=SciaRegs.SCIRXBUF.all;  // Read data

   }

   for(i=0;i<2;i++)                     // Check received data

   {

      if(rdataA[i] != ( (rdata_pointA+i) & 0x00FF) ) error();

   }

   rdata_pointA = (rdata_pointA+1) & 0x00FF;

   SciaRegs.SCIFFRX.bit.RXFFOVRCLR=1;   // Clear Overflow flag

   SciaRegs.SCIFFRX.bit.RXFFINTCLR=1;   // Clear Interrupt flag

   PieCtrlRegs.PIEACK.all|=0x100;       // Issue PIE ack

}

void scia_fifo_init()

{

  SciaRegs.SCICCR.all =0x0007;   // 1 stop bit,  No loopback

                                 // No parity,8 char bits,

                                 // async mode, idle-line protocol

  SciaRegs.SCICTL1.all =0x0003;  // enable TX, RX, internal SCICLK,

                                 // Disable RX ERR, SLEEP, TXWAKE

  SciaRegs.SCICTL2.bit.TXINTENA =1;

  SciaRegs.SCICTL2.bit.RXBKINTENA =1;

  SciaRegs.SCIHBAUD = 0x0000;

//  SciaRegs.SCILBAUD = SCI_PRD;

  SciaRegs.SCILBAUD = 0x00C2;

  SciaRegs.SCICCR.bit.LOOPBKENA =1; // Enable loop back

  SciaRegs.SCIFFTX.all=0xC022;

  SciaRegs.SCIFFRX.all=0x0022;

  SciaRegs.SCIFFCT.all=0x00;

  SciaRegs.SCICTL1.all =0x0023;     // Relinquish SCI from Reset

  SciaRegs.SCIFFTX.bit.TXFIFOXRESET=1;

  SciaRegs.SCIFFRX.bit.RXFIFORESET=1;

}

//===========================================================================

// No more.

//===========================================================================

Note: Here I am changing  the following lines:

Uint16 sdataA[5];    // Send data for SCI-A

Uint16 rdataA[5];    // Received data for SCI-A

Uint16 rdata_pointA; // Used for checking the received data

--> In the main loop the change is:

for(i = 0; i<5; i++)

  {

    sdataA[i] = i;

 }

--> In the TX  ISR the change is:

for(i=0; i< 5; i++)

   {

      SciaRegs.SCITXBUF=sdataA[i];     // Send data

   }

   for(i=0; i<5; i++)                 //Increment send data for next cycle

   {

      sdataA[i] = (sdataA[i]+1) & 0x00FF;

   }

--> In the RX  ISR the change is:

   for(i=0;i<5;i++)

   {

      rdataA[i]=SciaRegs.SCIRXBUF.all;  // Read data

   }

   for(i=0;i<5;i++)                     // Check received data

   {

      if(rdataA[i] != ( (rdata_pointA+i) & 0x00FF) ) error();

   }

Pls give me reply any one..