MSP430F2132 - UART Transmission

Hi everyone,

I'm trying to use the UART with a MSP430F2132 but the output is constantly giving be weird results. I want a standard 9600 - 8N1 output and send string of characters.

Here is the code :

#include <msp430.h> 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define GREEN_LED 		BIT7					// Greend led on P1OUT BIT 7
#define GREEN_LED_ON	(P1OUT |= GREEN_LED)	// Turn on green led

void Init_board( void );
void uart_init( void );

static inline void Wait_1sec( void );			// Wait 1 sec
static void UART_start_sending( void );			// Start sending throught UART
static unsigned char UART_get_rx( void );		// Get UART RX byte

volatile char UART_rx_string[32] = {0} ;			// Rx array
volatile char UART_tx_string[] = { '@', '1', '\r', '\0' } ;	// Tx array
volatile unsigned char i = 0 ;				// Counter for array
volatile unsigned char UART_sending = 0 ;	// UART sending flag

void main(void)
{
	WDTCTL = WDTPW | WDTHOLD;	// stop watch dog timer
	_EINT();					// Enable interrupts

	Init_board();				// Init inputs/outputs

	Wait_1sec();				// Wait Power-up

	// UART test
	{
		uart_init();			// Init UART in 9600 - 8N1
		unsigned int rxd = 0 ;	// Read byte

		UCA0TXBUF = 'A' ;		// Sample, test only
		Wait_1sec();
		UART_start_sending();	// Start sending string

		while(rxd == 0)
		{
			rxd = UART_get_rx();			// Get RX byte
			Wait_1sec();
		}

		GREEN_LED_ON ;
	}
}

static void UART_start_sending(void)
{
	UART_sending = 1 ;	// UART is sending
	IE2 |= UCA0TXIE;	// Enable interrupt
	UCA0TXBUF = UART_tx_string[i++] ;	// Fill buffer
}

static unsigned char UART_get_rx( void )
{
	return UART_rx_string[0];
}

static inline void Wait_1sec(void)
{
	// Enable WDT for 16ms waiting
	BCSCTL1 |= DIVA_0;			// ACLK /1 (diminue l'interval)
	WDTCTL 	= WDT_ADLY_250;		// WDT interval timer in ms (divided by BSCTL1)
	IE1 	|= WDTIE;           // Enable WDT interrupt

	volatile unsigned char i = 0;
	// Wait system to power-up	( 4 x 250ms )
	for(i = 4 ; i > 0 ; i--)
		__bis_SR_register(LPM0_bits + GIE);	// Enter LPM0

	WDTCTL = WDTPW | WDTHOLD;	// stop watch dog timer
}
void Init_board(void)
{
	/*
	 * P1.7		OUTPUT		GREEND LED					1
	 */
	P1DIR = 0x80;
	P2DIR = 0x00;

	/*
	 * P3.4		OUTPUT		UART_TXD					1
	 * P3.5		INPUT		UART_RXD					0
	 * P3.6		INPUT		UART_CLEAR_TO_SEND			0	// CTS and RTS connected
	 * P3.7		OUTPUT		UART_REQUEST_TO_SEND		1	// on Pmod RS232
	 */
	P3DIR = 0x90;

	P1OUT = 0x00;	// No outputs on P1DIR
	P2OUT = 0x00;	// No outputs on P2DIR
	P3OUT = 0x00;	// No outputs on P3DIR
}

void uart_init()
{
	WDTCTL = WDTPW + WDTHOLD;  				// Stop WDT

	if (CALBC1_1MHZ==0xFF)  				// If calibration constant erased
		while(1);          					// do not load, trap CPU!!

	DCOCTL = 0;                             // Select lowest DCOx and MODx settings
	BCSCTL1 = CALBC1_1MHZ;                  // Set DCO
	DCOCTL = CALDCO_1MHZ;

	//------------ Configuring the UART(USCI_A0) ----------------//

	P3SEL = 0x30;                          	// P3.4,5 = USCI_A0 TXD/RXD
	UCA0CTL1 |= UCSSEL_2;                   // SMCLK
	UCA0BR0 = 104;                          // 1MHz 9600
	UCA0BR1 = 0;                            // 1MHz 9600
	UCA0MCTL = UCBRS0;                      // Modulation UCBRSx = 1
	UCA0CTL1 &= ~UCSWRST;                   // **Initialize USCI state machine**
	IE2 |= UCA0RXIE;                        // Enable USCI_A0 RX interrupt

	//---------------- Enabling the interrupts ------------------//

	IE2 &= ~UCA0TXIE;		// Disable the Transmit interrupt
	IE2 |= UCA0RXIE;        // Enable the Receive  interrupt
}

#pragma vector=WDT_VECTOR
__interrupt void watchdog_timer (void)
{
	__bic_SR_register_on_exit(LPM0_bits);	// Clear LPM0 bits from 0(SR)
}
#pragma vector = USCIAB0RX_VECTOR
__interrupt void USCIAB0RX_ISR(void)
{
	// Check for UART RX
	if (UC0IFG & UCA0RXIFG)
	{
		IFG2 &= ~UCA0RXIFG; 			// Clear RX flag
		UART_rx_string[0] = UCA0RXBUF;
	}
}
#pragma vector = USCIAB0TX_VECTOR
__interrupt void USCIAB0TX_ISR(void)
{
	// Check for UART TX
	if (UART_sending)
	{
		char current_str = UART_tx_string[i++] ; // TX next character

		if( '\0' == current_str ) 	// TX over?
		{
			UART_sending = 0 ;		// UART stop sending
			i = 0;					// Counter to zero
			IE2 &= ~UCA0TXIE;		// Disable interrupt
		}
		else
			UCA0TXBUF = current_str;
	}
}

The 'A' character, alone, is giving me this :