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Problem in Receiving char on MSP430F449

Started by Unknown April 3, 2005
Hi,
I am having problem in receiving any char using the following code on
MSP430-449STK2 board from OLIMEX.

This code is as it is taken from example "fet440_usart01_19200" given
with IAR.

I have been struggling with this since ages.... :-(

Any help in this matter willbe appreciated.

Regards,
-mkh

#include <msp430x44x.h>

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;             // Stop WDT
  FLL_CTL0 |= XCAP14PF;                 // Configure load caps
  UTCTL0 = SSEL1;                       // UCLK = SMCLK
  UBR00 = 0x36;                         // 1MHz 19200
  UBR10 = 0x00;                         // 1MHz 19200
  UMCTL0 = 0x00;                        // no modulation
  UCTL0 = CHAR;                         // 8-bit character *SWRST*
  ME1 |= UTXE0 + URXE0;                 // Enable USART0 TXD/RXD
  IE1 |= URXIE0;                        // Enable USART0 RX interrupt
  P2SEL |= 0x30;                        // P2.4,5 = USART0 TXD/RXD
  P2DIR |= 0x10;                        // P2.4 output direction
  _EINT();                              // Enable interrupts

  for (;;)                              //
  {
    _BIS_SR(CPUOFF);                    // Enter LPM0
    _NOP();                             // Required only for C-spy
  }
}

interrupt[UART0RX_VECTOR] void usart0_rx (void)
{
  while ((IFG1 & UTXIFG0) == 0);        // USART0 TX buffer ready?
  TXBUF0 = RXBUF0;                      // RXBUF0 to TXBUF0
}

mahesh_shobhraj@hotmail.com wrote:
> Hi, > I am having problem in receiving any char using the following code on > MSP430-449STK2 board from OLIMEX. > > This code is as it is taken from example "fet440_usart01_19200" given > with IAR. > > I have been struggling with this since ages.... :-( > > Any help in this matter willbe appreciated. >
I can't go into it in detail, but how about this for an approach: (1) Take the character echo out of interrupt into a tight loop in main(). That eliminates interrupt snafus. Remember to test for character received etc. (2) Make it flash a LED when it receiuves a character. If it doesn't, the problem is on the receive side (have you selected port alternate functions etc.?) (3) Use a scope to check that the character is getting to the board at all, and if so, if anything at all comes out of the transmit port. Paul Burke