TMS320F280025C: TMS320F280025C SCI Communication not working in standalone mode

//
// Included Files
//
#include "driverlib.h"
#include "device.h"

// Globals
//
uint16_t frequency, measured_voltage;
float  voltage,  duty;
volatile uint16_t Data_Available = 0, Data_Available_TX=0 ;
//
// Send data for SCI-A
//
uint16_t tx_buffer[17];

//
// Received data for SCI-A
//
uint16_t rx_buffer[17];

//
// Function Prototypes
//
__interrupt void sciaTXFIFOISR(void);
__interrupt void sciaRXFIFOISR(void);
void initSCIAFIFO(void);
void error(void);

//

extern uint16_t RamfuncsLoadStart;
extern uint16_t RamfuncsLoadSize;
extern uint16_t RamfuncsRunStart;
// Main
//
void main(void)
{

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

    //
    // Setup GPIO by disabling pin locks and enabling pullups
    //
    Device_initGPIO();

    //
    // GPIO28 is the SCI Rx pin.
    //
    GPIO_setPinConfig(DEVICE_GPIO_CFG_SCIRXDA);
    GPIO_setDirectionMode(DEVICE_GPIO_PIN_SCIRXDA, GPIO_DIR_MODE_IN);
    GPIO_setPadConfig(DEVICE_GPIO_PIN_SCIRXDA, GPIO_PIN_TYPE_STD);
    GPIO_setQualificationMode(DEVICE_GPIO_PIN_SCIRXDA, GPIO_QUAL_ASYNC);

    //
    // GPIO29 is the SCI Tx pin.
    //
    GPIO_setPinConfig(DEVICE_GPIO_CFG_SCITXDA);
    GPIO_setDirectionMode(DEVICE_GPIO_PIN_SCITXDA, GPIO_DIR_MODE_OUT);
    GPIO_setPadConfig(DEVICE_GPIO_PIN_SCITXDA, GPIO_PIN_TYPE_STD);
    GPIO_setQualificationMode(DEVICE_GPIO_PIN_SCITXDA, GPIO_QUAL_ASYNC);

    //
    // 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();

    //
    // Interrupts that are used in this example are re-mapped to
    // ISR functions found within this file.
    //
    Interrupt_register(INT_SCIA_RX, sciaRXFIFOISR);
    Interrupt_register(INT_SCIA_TX, sciaTXFIFOISR);

    //
    // Initialize the Device Peripherals:
    //
    initSCIAFIFO();

    //
    measured_voltage=123;


    Interrupt_enable(INT_SCIA_RX);
    Interrupt_enable(INT_SCIA_TX);

    Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP9);

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

    //
    // IDLE loop. Just sit and loop forever (optional):
    //
    for(;;);
}

//
// error - Function to halt debugger on error
//
void error(void)
{
    asm("     ESTOP0"); // Test failed!! Stop!
    for (;;);
}

//
// sciaTXFIFOISR - SCIA Transmit FIFO ISR
//
__interrupt void sciaTXFIFOISR(void)
{

    //
    Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP9);
}

//
// sciaRXFIFOISR - SCIA Receive FIFO ISR
//
__interrupt void sciaRXFIFOISR(void)
{

    //
       //Parameters for transmit the VDC voltage to display
       //    measured_voltage = adcA7_VDC2_pu_avg*800;
                  tx_buffer[0] = 0x76;//(V)
                  tx_buffer[1] = 0x6f;//(o)
                  tx_buffer[2] = 0x6c;//(l)
                  tx_buffer[3] = 0x74;//(t)
                  tx_buffer[4] = 0x2E;//(.)
                  tx_buffer[5] = 0x74;//(t)
                  tx_buffer[6] = 0x78;//(x)
                  tx_buffer[7] = 0x74;//(t)
                  tx_buffer[8] = 0x3D;//(=)
                  tx_buffer[9] = 0x22;//(")
                  tx_buffer[10] = ((measured_voltage/100)+0x30);//(Voltage)
                  tx_buffer[11] = (((measured_voltage%100)/10)+0x30);//(Voltage)
                  tx_buffer[12] = ((measured_voltage%10)+0x30);//(Voltage)
                  tx_buffer[13] = 0x22;//(")
                  tx_buffer[14] = 0xFF;
                  tx_buffer[15] = 0xFF;
                  tx_buffer[16] = 0xFF;
           //end transmit the VDC voltage to display

        // Enable the TXFF interrupt again.
        //


      // Receive 17 Byte in Uart ISR
                              SCI_readCharArray(SCIA_BASE, rx_buffer, 17);
      //If the First Byte is Ox65, then move data in an actual variable from the Receive Buffer
                              if (rx_buffer[0] == 0x65)
                              {
                                  voltage = (((rx_buffer[7] - 0x30) * 100) + ((rx_buffer[8] - 0x30) * 10) + (rx_buffer[9] - 0x30));
                                  frequency = (((rx_buffer[12] - 0x30) * 100) + ((rx_buffer[13] - 0x30) * 10) + (rx_buffer[14] - 0x30));
                                  duty=(((rx_buffer[15] - 0x30)*10) + (rx_buffer[16] - 0x30));
                              }


               //   }
             SCI_writeCharArray(SCIA_BASE, tx_buffer, 17);

                          // Clear the SCI RXFF interrupt and acknowledge the PIE interrupt.
                          //
                         SCI_clearOverflowStatus(SCIA_BASE);
                          SCI_clearInterruptStatus(SCIA_BASE, SCI_INT_RXFF);
                          Interrupt_clearACKGroup(INTERRUPT_ACK_GROUP9);
}

//
// initSCIAFIFO - Configure SCIA FIFO
//
void initSCIAFIFO()
{
    //
    // 8 char bits, 1 stop bit, no parity. Baud rate is 9600.
    //
    SCI_setConfig(SCIA_BASE, DEVICE_LSPCLK_FREQ, 9600, (SCI_CONFIG_WLEN_8 |
                                                        SCI_CONFIG_STOP_ONE |
                                                        SCI_CONFIG_PAR_NONE));
    SCI_enableModule(SCIA_BASE);
    //SCI_enableLoopback(SCIA_BASE);
    SCI_resetChannels(SCIA_BASE);
    SCI_enableFIFO(SCIA_BASE);

    //
    // RX and TX FIFO Interrupts Enabled
    //
    SCI_enableInterrupt(SCIA_BASE, (SCI_INT_RXFF | SCI_INT_TXFF));
    SCI_disableInterrupt(SCIA_BASE, SCI_INT_RXERR);

    //
    // The transmit FIFO generates an interrupt when FIFO status
    // bits are less than or equal to 2 out of 16 words
    // The receive FIFO generates an interrupt when FIFO status
    // bits are greater than equal to 2 out of 16 words
    //
    SCI_setFIFOInterruptLevel(SCIA_BASE, SCI_FIFO_TX2, SCI_FIFO_RX2);
    SCI_performSoftwareReset(SCIA_BASE);

    SCI_resetTxFIFO(SCIA_BASE);
    SCI_resetRxFIFO(SCIA_BASE);
}

//
// End of file
//