TI的UART源代码例子感觉用不了

纹身灬猎人 2013-1-22 09:47 楼主

//******************************************************************************
// MSP430F5438 Demo - USCI_A0, 9600 UART, SMCLK, LPM0, Echo with over-sampling
//
// Description: Echo a received character, RX ISR used. Normal mode is LPM0.
// USCI_A0 RX interrupt triggers TX Echo.
// If UCOS16=1, UCBRx=Fbrclk/(16*Baudrate)
// Baud rate divider with UCBRx = 1MHz/(16*9600) = ~6.8
// ACLK = REFO = ~32768Hz, MCLK = SMCLK = default DCO = 32 x ACLK = 1048576Hz
// See User Guide for baud rate divider table
//
//             MSP430F5438
//          -----------------
//       /|\|                |
//       | |                |
//       --|RST             |
//          |                |
//          |    P3.4/UCA0TXD|------------>
//          |                | 9600 - 8N1
//          |    P3.5/UCA0RXD|<------------
//
// M Smertneck / W. Goh
// Texas Instruments Inc.
// September 2008
// Built with CCE Version: 3.2.2 and IAR Embedded Workbench Version: 4.11B
//******************************************************************************

#include "msp430x54x.h"

unsigned char x;

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                // Stop WDT
  P3SEL = 0x30;                            // P3.4,5 = USCI_A0 TXD/RXD
  UCA0CTL1 |= UCSWRST;                   // **Put state machine in reset**
  UCA0CTL1 |= UCSSEL_2;                   // SMCLK
  UCA0BR0 = 6;                            // 1MHz 9600 (see User's Guide)
  UCA0BR1 = 0;                            // 1MHz 9600
  UCA0MCTL = UCBRS_0 + UCBRF_13 + UCOS16; // Modln UCBRSx=0, UCBRFx=0,
                                          // over sampling
  UCA0CTL1 &= ~UCSWRST;                   // **Initialize USCI state machine**
  UCA0IE |= UCRXIE;                      // Enable USCI_A0 RX interrupt

  __bis_SR_register(LPM0_bits + GIE);    // Enter LPM0, interrupts enabled
  __no_operation();                      // For debugger
}

// 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:                         // Vector 4 - TXIFG
  break;
  default: break;
  }
}
按照里面所说，应该是PC机发送什么就是应该返回什么，但是程序烧完，也是出不来，出来也是乱码，       作为新手头痛啊！

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沙发纹身灬猎人

#include
#define uint  unsigned int
#define uchar unsigned char

int k,i;

uchar temp,sendchar,receivechar;
/*

unsigned char UCA3Read()
{
while (!(UCA3IFG&UCRXIFG));
return UCA3RXBUF;
}

void UCA3Write(  unsigned char sendchar)
{
  while (!(UCA3IFG&UCTXIFG));
UCA3TXBUF = sendchar;

}
*/
void main()
{
WDTCTL = WDTPW + WDTHOLD; // 关闭看门狗
P5DIR |= BIT4;

P5SEL|= (BIT2+BIT3); // 端口功能选择外部晶振XT2=24MHz
UCSCTL6 &= ~XT2OFF ; // XT2振荡器使能
UCSCTL6 |= XT2DRIVE0 + XT2DRIVE1  ; // XT2 最大驱动模式 24~32MHz
UCSCTL3 |= SELREF_2; //FLLREFCLK =REFOCLK  .且FLLREFCLK不分频
UCSCTL4 |= (SELA__REFOCLK+SELM__XT2CLK+SELS__XT2CLK); // ACLK=REFO,SMCLK=XT2,MCLK=XT2
do
{
   UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + XT1HFOFFG + DCOFFG); // 清除 XT2,XT1,DCO 错误标志
   SFRIFG1 &= ~OFIFG ; //清除晶振失效中断标志
}while(SFRIFG1&OFIFG);// 检测振荡器错误标志

UCA3CTL1|=UCSWRST; // 使能关闭状态机。USCI在复位后逻辑电平保持不变
P10SEL|= 0X30; // 选择引脚功能0x30
P10DIR|= 0X10 ; // 选择引脚功能
UCA3CTL1|= UCSSEL__SMCLK ; // UART_CLK = SMCLK

UCA3BR0= 0x0d ;  //粗调波特率控制寄存器0(UCA3BRx的低八位)9600
UCA3BR1=0x00 ;  //粗调波特率控制寄存器0(UCA3BRx的高八位)

UCA3MCTL|=(UCBRS_0 + UCBRF_3+UCOS16); // UCBRSx=0, UCBRFx=3  UCOS16=1过采样模式使能
UCA3CTL1&= ~UCSWRST  ; // 启动状态机

   while(1)
{
      receivechar = UCA3RXBUF;
      UCA3TXBUF = 0x55;
      for( i = 8000; i > 0; i--);

}

}

// 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 (!(UCA3IFG&UCRXIFG));
UCA3TXBUF = receivechar;
break;
  case 4:
while (!(UCA3IFG&UCTXIFG));
UCA3TXBUF = sendchar;
break;
  default: break;
  }
}

修改了一下，懵懵懂懂的，参照TI及一些厂家的程序，这个又可以用，而且关于那TXD与RXD的定义，定义在P10却是接在P5.4，5可以正常运行

点赞 2013-1-22 10:23

板凳纹身灬猎人

有修改了一个，但是无法进行收发，在12864液晶上显示，从PC机接收到的也是不准确的...

/////////////////////////////////////////////////////////////
//                MSP430F5438
//          -----------------
//       /|\|                |
//       | |                |
//       --|RST             |
//          |                |
//          |    P3.4/UCA0TXD|------------>
//          |                | 9600 - 8N1
//          |    P3.5/UCA0RXD|<------------
/////////////////////////////////////////////////////////////////

#include
#include "LCD12864.h"
#include "XT2.h"
#include "key_4_4.h"
#define CPU_F ((double)8000000)
#define delay_us(x) __delay_cycles((long)(CPU_F*(double)x/1000000.0))
#define delay_ms(x) __delay_cycles((long)(CPU_F*(double)x/1000.0))
#define uchar unsigned char
#define uint unsigned int
#define ulong unsigned long

unsigned char Key_Val;  //存放键值
uchar dat;

void max232()          //max232串口设置
{
  P3SEL = 0x30;                //P3.4/P3.5 = USCI_A0 TXD/RXD
  UCA0CTL1 |= UCSWRST;          //要在UCSWRST=1的情况下设置串口
  UCA0CTL1 |= UCSSEL__SMCLK;    //选择SMCLK=1.5MHz
  UCA0BR0 = 0x9c;                   // 1.5MHz/9600=156.25=0x009c
  UCA0BR1 = 0x00;
  UCA0MCTL |= UCBRS_2 + UCBRF_0; //0.25*8≈2,波特率调整
  UCA0CTL1 &= ~UCSWRST;          //初始化UART状态机
//  UCA0IE |= UCRXIE+UCTXIE;       //使能USART0 TXD/RXD
}

void key_P1()             //P1.0，P1.1独立键盘
{
  if((P1IN&0x0f)==0x02)
  {
delay_ms(5);
if((P1IN&0x0f)==0x02)
{
   P1OUT=BIT4;
   UCA0IE |= UCTXIE;       //(UCTxIE 置1 和UCRxIE 置 0)开发送中断，关闭收中断
}
while((P1IN&0x0f)==0x02);
  }

  if((P1IN&0x0f)==0x01)
  {
delay_ms(5);
if((P1IN&0x0f)==0x01)
{
   P1OUT=BIT5;
   UCA0IE|= UCRXIE;       //（UCTxIE 置0 和UCRxIE 置 1）关闭发送中断，开接收中断
}
while((P1IN&0x0f)==0x01);
  }
}

void main(void)
{
  // Stop watchdog timer to prevent time out reset
  WDTCTL = WDTPW + WDTHOLD;
  initsys();//TX2时钟初始化

  max232(); //max232串口设置

  P9DIR|=0xff;
  P9OUT =0xff;

  P8DIR|=0xff;
  P8OUT =0xff;

  P2DIR=0xf0;//按键接口设置P2.0-P2.3 为输入方向
  P2OUT|=0xf0;

  P1DIR=0xfC;//P1.0，P1.1为独立键盘

  LCD_Init(); //LCD12864初始化
  diaply();    //数据显示

_EINT();//打开全局中断
  while(1)
  {
key_P1();    //P1.0，P1.1独立键盘
key_display();//按键值显示
  }

}

// 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
  // Vector 2 - RXIFG
  case 2:
      dat = UCA0RXBUF; //接收数据
      LCD_WriteComm(0x8D);//写命令
      LCD_WriteByte(0x30+dat/100);
      LCD_WriteByte(0x30+dat/10%10);
      LCD_WriteByte(0x30+dat%10);
      UCA0IE=0x02;       //开发送中断，关闭收中断
      break;
  // Vector 4 - TXIFG
  case 4: delay_us(500);
      UCA0TXBUF = Key_Val;
      UCA0IE=0x01;       //关闭发送中断，开接收中断
      break;
  default: break;
  }
}

点赞 2013-1-24 16:34