TMS320F2800157: SCI transmitting and receiving problem.

Hi Siva,

Could you share your configuration code for the case where the last two bytes aren't being received?

Thank you,

Luke

We are using CCS 12.7 and C2000 5.2 examples.

We used sysConfig file to initialize the SCIB.

This is our main.c

#include "driverlib.h"
#include "device.h"
#include "board.h"
#include "c2000ware_libraries.h"

// Main
//
void main(void)
{

    //
    // Initialize device clock and peripherals
    //
    Device_init();

    //
    // Disable pin locks and enable internal pull-ups.
    //
    Device_initGPIO();

    //
    // Initialize PIE and clear PIE registers. Disables CPU interrupts.
    //
    Interrupt_initModule();

    //
    // Initialize the PIE vector table with pointers to the shell Interrupt
    // Service Routines (ISR).
    //
    Interrupt_initVectorTable();

    //
    // PinMux and Peripheral Initialization
    //
    Board_init();

    //
    // C2000Ware Library initialization
    //
    C2000Ware_libraries_init();

    //
    // Enable Global Interrupt (INTM) and real time interrupt (DBGM)
    //
    EINT;
    ERTM;

    uint16_t loopCounter = 0;
    uint16_t receivedChar;
    unsigned char *msg;
    uint16_t rxStatus = 0U;

    msg = "\r\n\n\nHello World!\0";
    SCI_writeCharArray(mySCI0_BASE, (uint16_t*)msg, 17);
    msg = "\r\nYou will enter a character, and the DSP will echo it back!\n\0";
    SCI_writeCharArray(mySCI0_BASE, (uint16_t*)msg, 62);

    //
    // Loop Forever
    //
    for(;;)
    {
        msg = "\r\nEnter a character: \0";
        SCI_writeCharArray(mySCI0_BASE, (uint16_t*)msg, 22);

        //
        // Read a character from the FIFO.
        //
        receivedChar = SCI_readCharBlockingFIFO(mySCI0_BASE);

        rxStatus = SCI_getRxStatus(mySCI0_BASE);
        if((rxStatus & SCI_RXSTATUS_ERROR) != 0)
        {
            //
            //If Execution stops here there is some error
            //Analyze SCI_getRxStatus() API return value
            //
            ESTOP0;
        }

        //
        // Echo back the character.
        //
        msg = "  You sent: \0";
        SCI_writeCharArray(mySCI0_BASE, (uint16_t*)msg, 13);
        SCI_writeCharBlockingFIFO(mySCI0_BASE, receivedChar);

        //
        // Increment the loop count variable.
        //
        loopCounter++;

    }
}

//
// End of File
//

First TX packet.

Excepted output :  "\r\n\n\nHello World!\0"

what we got :  "\r\n\n\nHello World"

Second TX packet

Excepted output :  "\r\nYou will enter a character, and the DSP will echo it back!\n\0"

what we got :  "!\0\r\nYou will enter a character, and the DSP will echo it back!"

we are missing last 2 bytes from the 1st packet 

On second Tx we get the missing 2bytes, then the rest of the second packet. Also the last 2bytes of packet are missing, which we get on 3rd TX. and this pattern continues.

Hi Siva,

I suspect this issue may be due to an overflow of the SCI TX buffer. Could you test this with a message less than 16 bytes long? Are the last two bytes still missing? Do you see this issue in FIFO and non-FIFO mode?

Thank you,

Luke

Yes, we tested with 10 bytes and still getting two missing byte at the end. We see this issue with non-FIFO mode.

When we enable FIFO then, more bytes are missing.

We don't know how to configure the FIFO size as we are using sysConfig to enable the communication protocols.

Hi Sheershak,

Are you testing with a launchpad or control card or custom board? I can test the issue on my side to determine the root cause.

Thank you,

Luke

Hi Luke,

We are using launchpad for testing.

Thank you,

 Siva Kumar