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CC430F6137: UART Problem When Only DC Powered - wihout Debugger

Part Number: CC430F6137

Hi everyone,

My problem is so weird and I couldn't handle it. 

I have a customized board which uses CC430F6137 uP and I programmed it. I would like to implement UART application and my code is that ;

#include <msp430.h>
#include "cc430x613x.h"
#include <msp430.h>
#include <string.h>
void terminal_write();
void UART_open();
void UART_close();
void main(void) {

WDTCTL = WDTPW | WDTHOLD; // Stop watchdog timer
//__delay_cycles( 2 * 1e7);
while(1)

{
UART_open();
printf("system working\r\n");
terminal_write("AT\r\n");

__delay_cycles(5000000);

//_bis_SR_register(LPM3_bits + GIE);
UART_close();

}

}

void terminal_write(char *info)
{
unsigned int i;


unsigned int len = strlen(info) ;
for(i=0;i<len;i++)
{

UCA0TXBUF=info[i];
__delay_cycles(10000);

}
}

void UART_open(){
P1SEL |= BIT5 + BIT6;
//UART Settings
UCA0CTL1 |= UCSWRST;
UCA0CTL1 |= UCSSEL0 ; // ACLK
UCA0BR0=3; //UCA0BR0 = 3 ; //32Khz / 9600 –>> 3
UCA0BR1=0; //UCA0BR1=0; // BAUD 9600; ( UCABR1 * 256 ) + UCABR0 = UCABRx see "slau259e.pdf"

UCA0MCTL=6 ; // see "slau259e.pdf" page 602 //
//UCA0MCTL =| BIT7 | BIT6 | BIT5 | BIT4 | BIT3 | BIT2 | BIT1 | BIT0 |
// |------- UCBRFx --------------|----UCBRSx----------|UCOS16|
// for 9600 baudrate at 32kHz UCBRFx = 0 , UCBRSx = 3 , UCOS16 = 0
// | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 |
// 0b00000110 = 0x06 = 6
UCA0CTL1 &=~ UCSWRST;//
UCA0CTL1 |= UCDORM;
}
void UART_close(){

P1SEL &= ~(BIT5 + BIT6);
UCA0CTL1 |= UCSWRST;
UCA0CTL1 &=~ UCDORM;

}

I'm using FET430--UIF debugger and there is no problem with it. If I run my program with debugger than it runs and there is no problem with UART communication but if I try to run it without debugger 

[I mean there is no need for debugging operation , I expect that program can run without debugger] I can't see any UART output when I use DC power supply(3.3 volt).Beside if I use only debugger without 3.3 v power supply then I can't receive the output signals properly. If I use both power supply and debugger than I can get the signals properly.

Thanks for your replies.

Huseyin.

  

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