51 MCU C language program (II) Timer/Counter interrupt

Use the timer/counter T0 to output a square wave with a period of 1s from P1.0
to make the light-emitting diode flash at 1HZ.
#include  //52 single-chip header file
#include //Library containing left and right circular shift sub-functions
#define uint unsigned int    //macro definition
#define uchar unsigned char  //macro definition
sbit P1_0=P1^0;
uchar tt;
void main()      //main function
{
 TMOD=0x01;//Set timer 0 to working mode 1
 TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 EA=1;//Open the total interrupt
 ET0=1;//Open the timer 0 interrupt
 TR0=1;//Start timer 0
 while(1);//Wait for the interrupt to occur
 
}

void timer0() interrupt 1
{
 TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 tt++;
 if(tt==20)
 {
  tt=0;
  P1_0=~P1_0;
 }
}

Procedure 2

Use timer/counter T1 to generate a timing clock, and
control 8 light-emitting diodes through P1 port,
so that the 8 indicator lights flash one by one in turn, with
a flashing frequency of 10 times/second (8 lights light up in turn for one cycle), in a cycle.
#include  //52 MCU header file
#include //Library containing left and right circular shift sub-functions
#define uint unsigned int    //Macro definition
#define uchar unsigned char  //Macro definition
sbit P1_0=P1^0;
uchar tt,a;
void main()      //Main function
{
 TMOD=0x01; //Set timer 0 to working mode 1
 TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 EA=1; //Open total interrupt
 ET0=1; //Open timer 0 interrupt
 TR0=1; //Start timer 0
 a=0xfe;
 while(1); //Wait for interrupt to occur
 
}

void timer0() interrupt 1
{
 TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 tt++;
 if(tt==2)
 {
  tt=0;
  P1=a;
  a=_crol_(a ,1);
 }
}

Procedure 3

 Two timers are used to control the buzzer sound at the same time. Timer 0 controls the frequency, and timer 1 controls the duration of
the same frequency. The square waves of 1, 10, 50, 100, 200, 400, 800, and 1k (hz) are output in turn at intervals of 2s.

#include  //52 MCU header file
#include //Library containing left and right circular shift sub-functions
#define uint unsigned int    //macro definition
#define uchar unsigned char  //macro definition
sbit beep=P2^3;
uchar tt;
uint fre,flag;

void main()      //Main function
{
 fre=50000;
 beep=0;
 TMOD=0x11;//Set timer 0 and timer 1 to working mode 1
 TH0=(65536-fre)/256;
 TL0=(65536-fre)%256;
 TH1=(65536-50000)/256;
 TL1=(65536-50000)%256;
 EA=1;//Open total interrupt
 ET0=1;//Open timer 0 interrupt
 ET1=1;
 TR1=1;
 TR0=1;//Start timer 0
 while(1);//Wait for interrupt to occur
 
}[page]

void timer0() interrupt 1   //Timer 0 interrupt
{
 TR0=0;    //After entering the interrupt, turn off the timer 0 interrupt to prevent the interrupt from being lost due to too many internal programs
 TH0=(65536-fre)/256;
 TL0=(65536-fre)%256;
 tt++;
 if(flag<40)    //The following ifs are used to select different frequencies
  if(tt==10)
   {
    tt=0;
    fre=50000;
    beep=~beep;
   }
 if(flag>=40&&flag<80)
  {
   tt=0;
   fre=50000;
   beep=~beep; 
  }
 if(flag>=80&&flag<120)
  {
   tt=0;
   fre=10000;
   beep=~beep; 
  }
 if(flag>=120&&flag<160)
  {
   tt=0;
   fre=5000;
   beep=~beep; 
  }
 if(flag>=160&&flag<200)
  {
   tt=0;
   fre=2500;
   beep=~beep; 
  }
 if(flag>=200&&flag<240)
  {
   tt=0;
   fre=1250;
   beep=~beep; 
  }
 if(flag>=240&&flag<280)
  {
   tt=0;
   fre=625;
   beep=~beep; 
  }
 if(flag>=280&&flag<320)
  {
   tt=0;
   fre=312;
   beep=~beep; 
  }
 if(flag>=320&&flag<360)
  {
   tt=0;
   fre=156;
   beep=~beep; 
  }
 TR0=1;
}
void timer1() interrupt 3  //Timer 1 interrupt is used to generate 2 seconds of time
{
 TH1=(65536-50000)/256;
 TL1=(65536-50000)%256;
 flag++;
 if(flag==360)
  {
    flag=0;
    fre=50000;
  }
}

Procedure 4

Use a timer to display 0, 1, 2, 3...C, D, E, F on the 6-digit digital tube in sequence at intervals of 500MS, and repeat.

#include  //52 MCU header file
#include //Library containing left and right circular shift sub-functions
#define uint unsigned int    //macro definition
#define uchar unsigned char  //macro definition
sbit dula=P2^6;       //digital tube segment selection latch end
sbit wela=P2^7;       ////digital tube bit selection latch end
uchar num,tt;
uchar code table[]={
0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};
void main()
{
 num=0;
 tt=0;
 TMOD=0x01;//Set timer 0 to working mode 1
 TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 EA=1;//Open the total interrupt
 ET0=1;//Open the timer 0 interrupt
 TR0=1;//Start timer 0
 dula=1;
 P0=0x3f;  //Send display 0 to the segment start
 . dula=0;//Close the segment selection latch to prevent garbled characters at the beginning.
 wela=1;//11101010
 P0=0xc0; //Open the six digital tubes and select
 wela=0;
 while(1)
 {
  if(tt==10)   //Every 10 interrupts are 500ms, and a display change is executed.
    {
    tt=0;
    num++;
    if(num==16)
    num=0;
    dula=1;
    P0=table[num];
    dula=0; 
   }
 }
}

void exter0() interrupt 1    // Timer 0 interrupt
{
 TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 tt++;
}