单片机其他外围设备的使用

蜂鸣器的使用：

蜂鸣器粗略设定频率，以20ms即50hz发声

#include#define uint unsigned int#define uchar unsigned charsbit fen = P2^6;void delay(uint z);main(){    while(1)    {        delay(1);//延时10毫秒注意这里输出的是20毫秒的方波                //因为方波要有正负的跳变才能算一个周期，这里?                //每隔10毫秒跳变一次，因此周期是200ms，频率是50Hz          fen = ~fen;    }}void delay(uint z){    uint x,y;    for(x=z;x>0;x--)        for(y=110;y>0;y--);    }

蜂鸣器精确控制发声：使用定时器

#include#define  uint unsigned int#define uchar unsigned charsbit  fen = P2^6;uchar num,ben;void init();void main(){    init();    while(1);}void init(){    TMOD = 0x11;    TH1 = (65536-50000)/256;    TL1 = (65536-50000)%256;    ET1 = 1;    EA = 1;    TR1 =1;    }void time1()interrupt 3{    TH1 = (65536-5000)/256;//定时一次是50毫秒    TL1 = (65536-5000)%256;    num++;    if(num==2)    {        num = 0;        fen = ~fen;    }}

蜂鸣器精确发声（控制其发出100ms,200ms,300ms,400ms,500ms 的频率

错误代码：

//这个程序调试了一上午吧，感觉有点不对劲，问题是出在  //定时器的打断上，即两个定时器都在工作的时候，会不会打断原来的定时器//这个程序实习实现的功能本来是使喇叭发声，发出//以100ms，200，300,400,500//本来应该听到5个频率，但是实际只是听到3个，说明中断发生了错位，中断之间产生了相互的影响     #include#define  uint unsigned int#define uchar unsigned charsbit  fen = P2^6;uchar num,flag,tt;void init();void main(){    init();    while(1);}void init(){    TMOD = 0x11;    TH1 = (65536-50000)/256;    TL1 = (65536-50000)%256;    TH0 = (65536-50000)/256;    TL0 = (65536-50000)%256;    ET1 = 1;    ET0 =1;    EA = 1;    TR0 =1;    TR1 =1;    }void time0()interrupt 1{    TH0 = (65536-50000)/256;    TL0 = (65536-50000)%256;    tt++;    switch(tt/20)    {        case 0:            flag = 1;            break;        case 1:            flag = 2;            break;        case 2:            flag = 3;            break;        case 3:            flag = 4;            break;        case 4:            tt=0;            flag = 5;            break;    }}void time1()interrupt 3{    TH1 = (65536-5000)/256;//定时一次是50毫秒    TL1 = (65536-5000)%256;    num++;    if(num==flag)    {        num = 0;        fen = ~fen;    }}

正确代码

/*                                                          同时用两个定时器控制蜂鸣器发声，  定时器0控制频率，定时器1控制同个   频率持续的时间，间隔2s依次输出  1，10，50,100，200,400,800,1k（hz）的方波?设晶振频率为12MHz。*/#include#include#define uint unsigned int#define uchar unsigned charsbit beep = P2^3;uchar tt;uint fre,flag;void main(){    fre = 50000;    beep = 0;    TMOD = 0x11;    TH0 = (65536-fre)/256;    TL0 = (65536-fre)%256;    TH1 = (65536- 50000)/256;    TL1 = (65536-50000)%256;    EA = 1;    ET0 = 1;    ET1 =1;    TR0 =1;    TR1 = 1;    while(1);}void timer0()interrupt 1{    TR0 = 0;//进入中断函数后关闭定时器0，以防止内部程序中断丢失    TH0 = (65536-50000)/256;    TL0 = (65536-50000)%256;    tt ++;    if(flag<40)        if(tt==10)            {                tt = 0;                fre = 50000;//分别用fre来选取频率定时50ms，所以中断产生的频率为10hz                beep = ~beep;            }    if(flag>=40&&flag<80)        {            tt = 0;            fre = 50000;//分别用fre来选取频率定时50ms，所以中断产生的频率为10hz            beep =~beep;        }    if(flag>=80&&flag<120)        {            tt = 0;            fre = 10000;//定时10ms，周期为20ms，频率为50hz             beep =~beep;        }     if(flag>=120&&flag<160)        {            tt = 0;            fre = 5000;//定时5毫秒，周期为10ms，频率为100zh             beep =~beep;        }     if(flag>=160&&flag<200)        {            tt = 0;            fre = 2500;//定时2.5，周期5ms，频率为200              beep =~beep;        }          if(flag>=200&&flag<240)        {            tt = 0;            fre = 1250;//定时1.25，周期2.5ms，频率400             beep =~beep;        }        if(flag>=240&&flag<280)        {            tt = 0;            fre = 625;//定时2.5，周期5ms，频率为800              beep =~beep;        }        if(flag>=280&&flag<320)        {            tt = 0;            fre = 312;//频率为1600            beep =~beep;        }        if(flag>=320&&flag<360)        {            tt = 0;            fre = 156;//频率为3200            beep =~beep;        }        TR0 = 1;        }void timer1()interrupt 3{        TH1 = (65536 - 50000)/256;        TL1 = (65536 - 50000)%256;        flag++;        if(flag == 360)        {            flag = 0;            fre = 50000;        }}