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超聲波測距的IAR程序- #include <msp430x14x.h>
- #include "cry1602.h"
- uchar tishi[]={"the distance is:"};
- uchar geshi[]={".cm"};//26.2cm
- uchar num[]={"0123456789 "};
- uchar Edge=1;
- uint RiseCapVal; //上升沿時(shí)刻捕獲值存放變量
- //uint TA_Overflow_Cnt; //TA溢出次數(shù)存放變量，可能距離遠(yuǎn)超過65535
- unsigned long int Period; //脈寬存放結(jié)果變量,高電平時(shí)間
- unsigned long int S; // 定義距離長度，單位厘米
- #define RISE 1
- #define FALL 0
- uint one,two,three;
- void Delay_ms(void);
- /**
- * main.c
- */
- void Conut(void)
- {
- one=S%1000/100;
- two=S%1000%100/10;
- three=S%1000%10 %10;
- Disp1Char(10,1,num[one]);
- Disp1Char(11,1,num[two]);
- Disp1Char(13,1,num[three]);
- }
- #pragma vector=TIMERA1_VECTOR
- __interrupt void Timer_A(void)
- {
- switch(TAIV)
- {
- case 2 :if(Edge==RISE)
- {
- RiseCapVal = TACCR1;
- TACCTL1 |= CAP+CM_2+CCIS_0+SCS+CCIE;//改為下降沿捕獲
- Edge = FALL;//下降沿捕獲標(biāo)志
- }
- else
- {
- _DINT();
- Period = TACCR1-RiseCapVal; //這里要注意是否考慮溢出，跟測試距離有關(guān)，希望大家拓展
- S=(Period*17)/100; // 距離計(jì)算 s=340m/s*Period/2*10^(-6)*1000(mm)
- TACCR1 = 0;
- TACCTL1|= CAP+CM_1+CCIS_0+SCS+CCIE;//改為上升沿捕獲
- Edge = RISE;//上升沿捕獲標(biāo)志
- _EINT();
- }
- break;
- case 4 : break;
- case 10: //TA_Overflow_Cnt++; //溢出標(biāo)志
- break;
- }
- }
- void init_timerA(void)
- {
- TACTL |= TASSEL_2+MC_2+TAIE+TACLR+ ID_3;//SMCLK,8MHz,8分頻，連續(xù)計(jì)數(shù)，中斷允許，計(jì)數(shù)器清零
- TACCTL1 |= CAP+CM_1+CCIS_0+SCS+CCIE;//捕獲模式，上升沿捕獲(CM_2)，CCI1A輸入，同步捕獲，中斷允許
- }
- void init_IO(void)
- {
- P1DIR |= BIT1; //P1.1輸出，普通I/O
- P1DIR &=~ BIT2; //P1.2輸入
- P1SEL |= BIT2; //P1.2第二功能，捕獲輸入
- P1OUT &=~BIT1; // 開始低電平，控制驅(qū)動(dòng)波形發(fā)生
- }
- void init_clk(void)
- {
- uchar i;
- BCSCTL1&=~XT2OFF; //打開XT振蕩器
- BCSCTL2|=SELM_2+SELS;//MCLK 8M and SMCLK 8M
- do
- {
- IFG1 &= ~OFIFG;//清除振蕩錯(cuò)誤標(biāo)志
- for(i = 0; i < 0xff; i++) _NOP();//延時(shí)等待
- }
- while ((IFG1 & OFIFG) != 0);//如果標(biāo)志為1繼續(xù)循環(huán)等待晶振起振
- IFG1&=~OFIFG;
- }
- void main(void)
- {
- /*下面六行程序關(guān)閉所有的IO口*/
- P1DIR = 0XFF;P1OUT = 0XFF;
- P2DIR = 0XFF;P2OUT = 0XFF;
- P3DIR = 0XFF;P3OUT = 0XFF;
- P4DIR = 0XFF;P4OUT = 0XFF;
- P5DIR = 0XFF;P5OUT = 0XFF;
- P6DIR = 0XFF;P6OUT = 0XFF;
- WDTCTL = WDTPW | WDTHOLD; // stop watchdog timer
- LcdReset();
- DispStr( 0, 0,tishi);
- Disp1Char(12,1,geshi[0]);
- Disp1Char(14,1,geshi[1]);
- Disp1Char(15,1,geshi[2]);
- init_clk();
- init_IO();
- _EINT(); //開全局中斷
- while(1)
- {
- init_timerA();
- P1OUT |= BIT1; // P1.1 高電平，超過10us
- Delay5ms();
- P1OUT &=~BIT1;
- Delay5ms();
- Conut();
- Delay_ms();
- }
- }
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超聲波測距.zip
2020-9-18 19:21 上傳
點(diǎn)擊文件名下載附件
下載積分: 黑幣 -5
115.6 KB, 下載次數(shù): 18, 下載積分: 黑幣 -5
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