MSP430FR2311: UART Commincation: Unable to Transmit Serial Data

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//******************************************************************************
//   MSP430FR231x Demo - USCI_A0 External Loopback test @ 115200 baud
//
//  Description: This demo connects TX to RX of the MSP430 UART
//  The example code shows proper initialization of registers
//  and interrupts to receive and transmit data. If data is incorrect P1.0 LED is
//  turned ON.
//  ACLK = n/a, MCLK = SMCLK = BRCLK = DCODIV ~1MHz.
//
//                MSP430FR2311
//             -----------------
//         /|\|                 |
//          | |                 |
//          --|RST              |
//            |                 |
//            |                 |
//            |     P1.7/UCA0TXD|----
//            |                 |   |
//            |     P1.6/UCA0RXD|----
//            |                 |
//            |            P1.0 |--> LED
//            |                 |
//
//   Darren Lu
//   Texas Instruments Inc.
//   Oct. 2015
//   Built with IAR Embedded Workbench v6.30 & Code Composer Studio v6.1
//******************************************************************************
#include <msp430.h>

unsigned char RXData = 0;
unsigned char TXData = 1;

int main(void)
{
    WDTCTL = WDTPW | WDTHOLD;                 // Stop watchdog timer

    PM5CTL0 &= ~LOCKLPM5;                     // Disable the GPIO power-on default high-impedance mode
                                              // to activate previously configured port settings
    P1DIR |= BIT0;
    P1OUT &= ~BIT0;                           // P1.0 out low

    // Configure UART pins
    P1SEL0 |= BIT6 | BIT7;                    // set 2-UART pin as second function

    // Configure UART
    UCA0CTLW0 |= UCSWRST;                     // Put eUSCI in reset
    UCA0CTLW0 |= UCSSEL__SMCLK;
    // Baud Rate calculation
    UCA0BR0 = 8;                              // 1000000/115200 = 8.68
    UCA0MCTLW = 0xD600;                       // 1000000/115200 - INT(1000000/115200)=0.68
                                              // UCBRSx value = 0xD6 (See UG)
    UCA0BR1 = 0;
    UCA0CTLW0 &= ~UCSWRST;                    // Initialize eUSCI
    UCA0IE |= UCRXIE;                         // Enable USCI_A0 RX interrupt

    while (1)
    {
        while(!(UCA0IFG & UCTXIFG));
        UCA0TXBUF = TXData;                   // Load data onto buffer

        __bis_SR_register(LPM0_bits|GIE);     // Enter LPM0
        __no_operation();                     // For debugger
    }
}

#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=USCI_A0_VECTOR
__interrupt void USCI_A0_ISR(void)
#elif defined(__GNUC__)
void __attribute__ ((interrupt(USCI_A0_VECTOR))) USCI_A0_ISR (void)
#else
#error Compiler not supported!
#endif
{
    switch(__even_in_range(UCA0IV,USCI_UART_UCTXCPTIFG))
    {
        case USCI_NONE: break;
        case USCI_UART_UCRXIFG:
              UCA0IFG &=~ UCRXIFG;            // Clear interrupt
              RXData = UCA0RXBUF;             // Clear buffer
              if(RXData != TXData)            // Check value
              {
                  P1OUT |= BIT0;              // If incorrect turn on P1.0
                  while(1);                   // trap CPU
              }
              TXData++;                             // increment data byte
              __bic_SR_register_on_exit(LPM0_bits); // Exit LPM0 on reti
              break;
        case USCI_UART_UCTXIFG: break;
        case USCI_UART_UCSTTIFG: break;
        case USCI_UART_UCTXCPTIFG: break;
    }
}