Using timer to realize simple clock function

#include


#define PORTLEN P0


sbit bit_select = P2^0;
sbit seg_select = P2^1;


unsigned char src[16] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f ,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
unsigned char qrc [8] = {0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f}; unsigned
char second1[8];
shi = 0;
unsigned char fen = 0;
unsigned char miao = 0;


void timer0_init(void)
{
 EA = 1;
 TMOD |= 0x01;
 TH0 = (65536 - 1000) / 256;
 TL0 = (65536 - 1000) % 256; //Set the initial value of timer T0, generate an interrupt once every 1ms
 ET0 = 1; //Open Timer T0 interrupt
 TR0 = 1; //Turn on timer T0 and start adding 1 every 1ms
} 


void timer1_init(void)
{
 EA = 1;
 TMOD |= 0x10;
 TH1 = (65536 - 1000) / 256;
 TL1 = ( 65536 - 1000) % 256; //Set the initial value of timer T1, generate an interrupt every 1ms
 ET1 = 1; //Turn on timer T1 interrupt
 TR1 = 1; //Turn on timer T1, start adding 1 every 1ms
}


void main()
{
        timer0_init();
 imer1_init();
 while(1);
}


void display()//Dynamic display clock
{
         static unsigned char i = 0;
 PORTLEN = 0x0; // Eliminate ghosting
 seg_select = 1;
 seg_select = 0;

 PORTLEN = 0xff;
 bit_select = 1;
 bit_select = 0;

 PORTLEN = second1[i];
 seg_select = 1;
 seg_select = 0;

 PORTLEN = qrc[i];
 bit_select = 1;
 bit_select = 0;
 
 i++;
 if(8 == i)
{
 i = 0;
}

}



void timer0_isr() interrupt 1
{
 static unsigned char i = 0;
          TH0 = (65536 - 20000) / 256;
 TL0 = (65536 - 20000) % 256; //Set the initial value of the timer to generate an interrupt every 20ms

 i++;
 if(50 == i) //Count down to 1s
  {
 i = 0;
                          miao++;
 if(60 == miao)
  {   
  miao = 0;
           fen++;
   if (60 == fen)
    {
    fen = 0;
    shi++;
    if(24 == shi)
     {
    shi = 0;
      }
   }
}
         }
second1[0] = src[shi / 10]; // Assign values ​​to each digit of the digital tube
second1[ 1] = src[shi % 10];
second1[2] = 0x40;
second1[3] = src[fen / 10];
second1[4] = src[fen % 10];
second1[5] = 0x40;
second1[ 6] = src[miao / 10];
second1[7] = src[miao % 10];
}


void timer1_isr() interrupt 3
{
          TH1 = (65536 - 1000) / 256; re-initialize
 TL1 = (65536 - 1000) % 256;
 display();
}