MSP430FR5969: I am trying to use the UART port but its not working as intended

Tool/software:

Hello TI Team,

I am using the TI MSP430FR5969 microcontroller to blink a LED P4.6 whenever the UART RX recieves "t" from the keyboard. I have my code copied down to this text and the problem is whenever i am pressing t nothing is happening. I am quite sure that the code is correct and the MSP430 is completetly new. Can someone still review the code or provide solution to this problem.

code 

#include <msp430.h>

/**
* main.c
*/
int main(void)
{
WDTCTL = WDTPW | WDTHOLD; // stop watchdog timer

UCA0CTLW0 |= UCSWRST;

UCA0CTLW0 |= UCSSEL__SMCLK;
UCA0BRW = 8;
UCA0MCTLW = 0XD600;

// Setup the ports

P2SEL0 &= ~BIT1;
P2SEL1 |= BIT1;

P4DIR |= BIT6;
P4OUT &= ~BIT6;

PM5CTL0 &= ~LOCKLPM5;

UCA0CTLW0 &= ~UCSWRST;

UCA1IE |= UCRXIE;
__enable_interrupt();

while(1){

}

return 0;
}

#pragma vector = USCI_A0_VECTOR
__interrupt void RX_vector(void)
{
if (UCA0RXBUF == "t")
{
P4OUT ^= BIT6;

}
} 

Thank you!

Best regards,

Pukhraj Singh