用法UART与PC通信实现msp430g2553单片机超声波测距示例_

1、用法UART与PC通信实现msp430g2553单片机超声波测距示例_ 这篇文章主要介绍了用法UART与PC通信实现msp430g2553单片机超声波测距示例,需要的伴侣可以参考下. 适用于msp430g2553单片机 用法到了hc-sr04超声测距模块，用法UART与PC通信。 代码如下: #include long current_time;/最近一次测得时间 /*MyPro*/ #define LED_1 BIT0 #define SW_2 BIT3 #define TA1_1 BIT2 /TA0.1 HC-SR04 Echo #define TRIG BIT4 /HC-SR04 Tri

2、g #define ACCU_GRD 7 /Accuracy Grade xxx.x+ #define MIN_UNIT_TO1M 1000 /1 m to 1 mm /*TIMER0*/ #define SOUR_CLK 1045000 #define DIV_CLK_1 1 #define SYS_CLK_SIG_1 SOUR_CLK/DIV_CLK_1 #define DISTANCE 45/dm #define TIMER_RIG_MAX 0xffff #define MAX_TIME_1 DISTANCE*2/34*SYS_CLK_SIG_1 #ifdef MAX_TIME_1 #d

3、efine SYS_CLK SYS_CLK_SIG_1 #endif #define UART_TXD BIT2 void init_timer1() P2SEL |= TA1_1; /TA1.1 CCI1B be used P2DIR = TA1_1; TA1CTL = MC_0 + TASSEL_2; /TimerA_0 stop mode,clock=1Mhz TA1CCTL1 = CCIE + SCCI + CCIS_1 + SCS + CAP + CM_2; /TA0CC1 capture mode + down edge /*UART*/ void init_uart() /USC

4、I 初始化函数 UCA0CTL1 |= UCSWRST; /初始化串口寄存器 UCA0CTL1 |= UCSSEL_2; /选择子系统时钟 1.045MHz UCA0BR0 = 0x6d; /波特率为9600 UCA0BR1 = 0x00; P1SEL |= UART_TXD; P1SEL2 |= UART_TXD; P1DIR |= UART_TXD; /将P1.2设为其次功能 UCA0CTL1 = UCSWRST; /初始化结束 long cal_distance() /通过测得时间计算距离 return (long)(340*(0.5000*current_time/SYS_CLK)*M

5、IN_UNIT_TO1M); void delay() /粗略延迟 unsigned char i,j; for(i=124;i0;i-) for(j=8;j0;j-); static char * translater(long distance) /将测得的距离以字符串形式存储 static char transACCU_GRD; int i; long f; trans0= ; if(distance) for(i=1,f=MIN_UNIT_TO1M;i if(i=4) transi = .; continue; transi = 0+ distance/f; distance %= f

6、; f /= 10; transACCU_GRD-1 = ; return trans; void once_pro() /发一次超声波 if(TA1CCTL1 COV) TA1CCTL1 = COV; if(!(P1IN BIT3) TA1R = 0; P1OUT |= TRIG; /Trig 10 us 高电平 _EINT(); TA1CTL |= MC_2; /continue mode P1OUT = TRIG; P1OUT |= LED_1; while(TA1CCTL1 CCIFG); /等待 捕捉中断结束 else P1OUT = LED_1; _DINT(); void uar

7、t_txstring(char *string) /UART_TX 发送一个串 int i=0; while(stringi+) switch (i) /过滤无效 0 case 1:if(stringi=0) continue; case 2:if(stringi=0stringi-1=0) continue; UCA0TXBUF = stringi; delay(); /*UART_ISR*/ #pragma vector = USCIAB0TX_VECTOR _interrupt void usci_txdistance() /向 PC 发送 测得的距离 uart_txstring(nr)

8、; uart_txstring( Current ); uart_txstring( distance: ); uart_txstring(translater(cal_distance(); uart_txstring( cm); IE2 = UCA0TXIE; /*TIMER0_INT_ISR*/ #pragma vector = TIMER1_A1_VECTOR _interrupt void capture() current_time = TA1CCR1; TA1CTL = MC_2; TA1CCTL1 = CCIFG; /清CC1中断标记位 IE2 |= UCA0TXIE; /*Main*/ void main() WDTCTL = WDTPW + WDTHOLD; /关狗 DCOCTL = 0; BCSCTL1 = CALBC1_1MHZ; DCOCTL = CALDCO_1MHZ; P1OUT = 0; P2OUT = 0; P1REN |= SW_2; P2REN |= TA1_1; P1OUT |= SW_2; P1DIR = SW_2; P1DIR = TRIG + L