AVR 1-99 seconds 1602 start and stop display-EEWORLD

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#include

#define uchar unsigned char
#define uint unsigned int

uint sec=0; //second variable
uint cnt=0; //count variable
uint on=0; //start/stop status variable

uchar str1[16]="The time: sec"; //All strings here have a certain length to eliminate display abnormalities caused by the pointer deviation of uncertain display codes
uchar start[16]=" start ";
uchar stop[16]=" stop ";

#include "1602.h"

void port_init()
{
PORTA=0xff;
DDRA=0xff;
PORTB=0xff;
DDRB=0xff;
PORTD=0xff;
DDRD=0xff;
}

void init()
{
MCUCR=0x0a;
GICR=0xc0;
SREG=0x80;
}

void time0_init()
{
TCCR0=0x03;
TIMSK=0x01;
TCNT0=0x83;
}

void showtime(uint time)
{
displayonechar(10,0,(time/10)+48);
displayonechar(11,0,(time%10)+48);
}

void main()
{

port_init();

//1602 device initialization
delay(15);
writecmd(0x38);
delay(5);
writecmd(0x38);
delay(5);
writecmd(0x38);
writecmd(0x80);
writecmd(0x01);
writecmd(0x06);
writecmd(0x0c);
delay(500);
//End of initialization

      init();
time0_init();
while(1)
{

   displaychar(0,0,str1);
   showtime(sec); //Display time value (seconds) Repeatedly overwrite these 2 digits to achieve the display effect
   delay(20);
}
}

#pragma vector = 0x24 //Timer 0 overflow (timing seconds)
__interrupt void time0()
{
TCNT0=0x83;
if(on==1) //Start flag
{
cnt++;
if(cnt==1000)
{
sec++;cnt=0;
}
if(sec>100)sec=0;
}
}

#pragma vector = 0x04 //INT0 interrupt service routine
__interrupt void int0()
{
on=1;
writecmd(0x01); // Clear screen
displaychar(0,1,start); // Display start character
displaychar(0,0,str1); // Display original character
showtime(sec);

}

#pragma vector = 0x08 //INT1 interrupt service routine
__interrupt void int1()
{
on=0;
writecmd(0x01); //Clear screen
displaychar(0,1,stop); //Display stop character
displaychar(0,0,str1); //Display original character
showtime(sec);

}

Keywords：AVR Reference address：AVR 1-99 seconds 1602 start and stop display

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