msp430f5529在修改主时钟频率为40mhz后就串口接受不到数据,注释掉修改语句后数据会出现问题输入数据的是1,debug测试出来的是50多
void USART0_Config(void)
{
//串口初始化
P3SEL |= BIT3+BIT4 ; // P5.6,7 = USCI_A1 TXD/RXD
UCA0CTL1 |= UCSWRST; // Put state machine in reset
UCA0CTL1 |= UCSSEL_1; // ACLK
UCA0BR0 = 0x03; //0x03; // 32768Hz 9600 波特率为9600
UCA0BR1 = 0x00; //0x00; // 32768Hz 9600
UCA0MCTL |= UCBRS_3 + UCBRF_0 ; // Modulation UCBRSx=1, UCBRFx=0
UCA0CTL1 &= ~UCSWRST; // Initialize USCI state machine
UCA0IE |= UCRXIE; // Enable USCI_A1 RX interrupt 使能中断
_EINT();
}
void USART1_Config(void)
{
//串口初始化
P4SEL |= BIT4+BIT5 ; // P5.6,7 = USCI_A1 TXD/RXD
UCA1CTL1 |= UCSWRST; // **Put state machine in reset**
UCA1CTL1 |= UCSSEL_1; // ACLK
UCA1BR0 = 0x03; // 32768Hz 9600 波特率为9600
UCA1BR1 = 0x00; // 32768Hz 9600
UCA1MCTL |= UCBRS_3 + UCBRF_0; // Modulation UCBRSx=1, UCBRFx=0
UCA1CTL1 &= ~UCSWRST; // **Initialize USCI state machine**
UCA1IE |= UCRXIE; // Enable USCI_A1 RX interrupt 使能中断 //
_EINT();
}
void send0_buf(unsigned char *ptr) //发送字符串
{
while(*ptr != '\0')
{
while(!(UCA0IFG & UCTXIFG));
UCA0TXBUF = *ptr;
ptr++;
delay(10);
}
}
void send1_buf(unsigned char *ptr) //发送字符串
{
while(*ptr != '\0')
{
while(!(UCA1IFG & UCTXIFG));
UCA1TXBUF = *ptr;
ptr++;
delay(10);
}
}
//uart0 接受中断过
#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
//阻塞式返回值
while (!(UCA0IFG&UCRXIFG)); // USCI_A0 TX buffer ready?
UCA0IFG &= ~UCRXIFG;//清除标志位
rx = UCA0RXBUF;
break;
case 4:
break; // Vector 4 - TXIFG
default:
break;
}
}
![img](}
我就是想问一下为什么改成40mhz就不行,debug时数据为什么会有多余的值