modbus-RTU implementation on MSP430FG4618 through UART at 9600 boudrate pls help me

hi this my uart code for msp430fg4618 this code is working so i want modbus plc signal communicate with msp430fg4618 through uart . how to change this code . pls send corrected code

modbus signal how to configure boud rate etc in this code\

pls send corrected code

with modbus implementation code

#include <msp430xg46x.h>

int main(void)
{
  volatile unsigned int i;

  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  P4SEL |= 0x03;                            // P4.1,0 = USART1 TXD/RXD
  FLL_CTL0 |= XCAP14PF;                     // Configure load caps

  do
  {
  IFG1 &= ~OFIFG;                           // Clear OSCFault flag
  for (i = 0x47FF; i > 0; i--);             // Time for flag to set
  }
  while ((IFG1 & OFIFG));                   // OSCFault flag still set?

  ME2 |= UTXE1 + URXE1;                     // Enable USART1 TXD/RXD
  U1CTL |= CHAR;                            // 8-bit character
  U1TCTL |= SSEL1 + SSEL0 + URXSE;          // UCLK = SMCLK, start edge detect
  U1BR0 = 0x37;                             // 1MHz 19200
  U1BR1 = 0x00;                             // 1MHz 19200
  U1MCTL = 0x6B;                            // 1MHz 19200 modulation
  U1CTL &= ~SWRST;                          // Initialize USART state machine
  IE2 |= URXIE1;                            // Enable USART1 RX interrupt

  for (;;)
  {
    while (!(U1TCTL & TXEPT));              // Confirm no TXing before --> LPM3
    _DINT();                                // Disable interrupts for flag test
    _NOP();
    if (!(U1TCTL & SSEL0))
     _BIS_SR(LPM0_bits + GIE);              // RX'ing char, LPM, int's active
    else
     _BIS_SR(LPM3_bits + GIE);              // Enter LPM3, int's active
  }
}

#pragma vector=USART1RX_VECTOR
__interrupt void usart1_rx (void)
{
  if ((IFG2 & URXIFG1))                     // Test URXIFG0
  {
    while (!(IFG2 & UTXIFG1));              // USART1 TX buffer ready?
    U1TXBUF = U1RXBUF;                      // RXBUF0 to TXBUF0
    _BIC_SR_IRQ(LPM3_bits);                 // Exit LPM3 after reti
    U1TCTL |= SSEL0;                        // SSEL0 = 1, no RX activity
  }
  else                                      // Start edge
  {
    U1TCTL &= ~URXSE;                       // Clear URXS signal
    U1TCTL |= URXSE;                        // Re-enable edge detect
    _BIC_SR_IRQ(SCG1 + SCG0);               // DCO reamins on after reti
    U1TCTL &= ~SSEL0;                       // SSEL0= 0, RX activity
  }
}