The use of other peripheral devices of single chip microcomputer

Use of buzzer:

The buzzer frequency is roughly set to 20ms or 50hz.

#include

#define uint unsigned int

#define uchar unsigned char

sbit fen = P2^6;

void delay(uint z);

main()

{

    while(1)

    {

        delay(1); //Delay 10 milliseconds Note that the output here is a 20 millisecond square wave

                //Because a square wave must have positive and negative transitions to count as a cycle, here?

                //It jumps every 10 milliseconds, so the period is 200ms and the frequency is 50Hz  

        fen = ~fen;

    }

}

void delay(uint z)

{

    uint x,y;

    for(x=z;x>0;x--)

        for(y=110;y>0;y--);

}

Precise control of buzzer sound: using a timer

#include

#define uint unsigned int

#define uchar unsigned char

sbit 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; //The timing is 50 milliseconds

    TL1 = (65536-5000)%256;

    num++;

    if(num==2)

    {

        num = 0;

        fen = ~fen;

    }

}

The buzzer can emit precise sound (control the frequency of 100ms, 200ms, 300ms, 400ms, 500ms)

error code:

//I have been debugging this program for a whole morning, and I feel something is wrong. The problem is  

//Timer interruption, that is, when two timers are working, will the original timer be interrupted?

//The function of this program is to make the speaker sound.

//100ms, 200, 300, 400, 500

//Originally, 5 frequencies should be heard, but only 3 are actually heard, indicating that the interrupts are misaligned and the interrupts affect each other     

#include

#define uint unsigned int

#define uchar unsigned char

sbit 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; //The timing is 50 milliseconds

    TL1 = (65536-5000)%256;

    num++;

    if(num==flag)

    {

        num = 0;

        fen = ~fen;

    }

}

Correct code

/*                                                          

Use two timers to control the buzzer sound at the same time.  

Timer 0 controls the frequency, and Timer 1 controls the same   

The duration of the frequency is output in sequence at 2s intervals.  

1, 10, 50, 100, 200, 400, 800,

1k (hz) square wave?

Assume the crystal frequency is 12MHz.

*/

#include

#include

#define uint unsigned int

#define uchar unsigned char

sbit 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; //After entering the interrupt function, turn off timer 0 to prevent the internal program interrupt from being lost

    TH0 = (65536-50000)/256;

    TL0 = (65536-50000)%256;

    tt++;

    if(flag<40)

        if(tt==10)

            {

                tt = 0;

                fre = 50000; //Use fre to select the frequency timing of 50ms, so the frequency of the interrupt is 10hz

                beep = ~beep;

            }

    if(flag>=40&&flag<80)

        {

            tt = 0;

            fre = 50000; //Use fre to select the frequency timing of 50ms, so the frequency of the interrupt is 10hz

            beep =~beep;

        }

    if(flag>=80&&flag<120)

        {

            tt = 0;

            fre = 10000; //timing 10ms, period 20ms, frequency 50hz 

            beep =~beep;

        }

     if(flag>=120&&flag<160)

        {

            tt = 0;

            fre = 5000; // Timing 5 milliseconds, period 10ms, frequency 100zh 

            beep =~beep;

        }

     if(flag>=160&&flag<200)

        {

            tt = 0;

            fre = 2500; //timing 2.5, period 5ms, frequency 200  

            beep =~beep;

        }

          if(flag>=200&&flag<240)

        {

            tt = 0;

            fre = 1250; //timing 1.25, period 2.5ms, frequency 400 

            beep =~beep;

        }

        if(flag>=240&&flag<280)

        {

            tt = 0;

            fre = 625; //timing 2.5, period 5ms, frequency 800  

            beep =~beep;

        }

        if(flag>=280&&flag<320)

        {

            tt = 0;

            fre = 312; // frequency is 1600

            beep =~beep;

        }

        if(flag>=320&&flag<360)

        {

            tt = 0;

            fre = 156; // frequency is 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;

        }

}