Hi All,
I’m working with the CC430F137 chip.
While it’s P1.7 and P1.6 are connected to a UART source of 4800 I’ve configured the program as follows:
int main(void)
{
i = 0;
P1DIR |= BIT6; // Set P1.6 as TX output
P1SEL |= BIT6 + BIT7; // Select P1.6 & P1.7 to UART function
while (1)
{
UART_function ();
if (i >= 199)
break;
}
}
void UART_function (void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
PMAPPWD = 0x02D52; // Get write-access to port mapping regs
P1MAP6 = PM_UCA0TXD; // Map UCA0TXD output to P1.6
P1MAP7 = PM_UCA0RXD; // Map UCA0RXD output to P1.7
PMAPPWD = 0; // Lock port mapping registers
P1DIR |= BIT6; // Set P1.6 as TX output
P1SEL |= BIT6 + BIT7; // Select P1.6 & P1.7 to UART function
*pNMEA_Buffer = UCA0RXBUF; // Read the info
pNMEA_Buffer++; // update the address
UCA0CTL1 |= UCSWRST; // **Put state machine in reset**
UCA0CTL1 |= UCSSEL_1; // CLK = ACLK
UCA0BR0 = 0x06; // 4800
UCA0BR1 = 0x00; //
UCA0MCTL |= UCBRS_7+UCBRF_0; // Modulation UCBRSx=6, UCBRFx=0
UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine**
UCA0IE |= UCRXIE; // Enable USCI_A1 RX interrupt
}
// Echo back RXed character, confirm TX buffer is ready first
#pragma vector=USCI_A0_VECTOR
__interrupt void USCI_A0_ISR(void)
{
switch(__even_in_range(UCA0IV,4))
{
case 0:break; // Vector 0 - no interrupt
case 2: // Vector 2 - RXIFG
while (!(UCA0IFG&UCTXIFG)); // USCI_A0 TX buffer ready?
UCA0TXBUF = UCA0RXBUF; // TX -> RXed character
break;
case 4:break; // Vector 4 - TXIFG
default: break;
}
}
But it seems that I can’t read the correct baud rate (i.e. 4800).
Can someone check my 4800 configuration?
Thanks,
Shimo
