Question

This is a atmega128 source to make a clock using the timer interrupt. I want to add source if i press switch (PIND==0x0FE&&PIND==0x0FD) then below program would be running .

#include<io.h>

int position=0,BJT[4]={0xFE,0xFD,0xFB,0xF7};

int number=0,segment[10]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};

int msec=0, sec=0, min=0;

void main()

{

DDRA=0xFF;

PORTA=0XFF;

DDRB=0xFF;

PORTB=0xFF;

TCCR0=0x04;

TIMSK=0x01;

SREG=0x80;

while(1){}

}

interrupt[TIM0_OVF]void timer0_ovf_isr()

{

TCNT0=0x06;

PORTA=BJT[position];

if(position==0)number=sec%10;

if(position==1)number=sec/10;

if(position==2)number=min%10;

if(postion==3)number=min/10;

PORTB=segment[number];

position++;

if(position>3)position=0;

msec++;

if(msec==1000)

{

msec=0;

sec++;

}

if(sec==60)

{

sec=0;

min++;

}

if(min==60)min=0;

}

Answer 1

/*
        Generating 10 ms delay pulse on PORTB using ATmega128 Timer interrupt
 */ 


#include <avr/io.h>
#include <avr/interrupt.h>

/* timer0 overflow interrupt */
ISR(TIMER0_OVF_vect)
{
        PORTB=~PORTB;           /* Toggle PORTB */
        TCNT0 = 0xB2;
}
(PIND==0x0FE&&PIND==0x0FD)
{

int position=0,BJT[4]={0xFE,0xFD,0xFB,0xF7};

int number=0,segment[10]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};

int msec=0, sec=0, min=0;

void main()

{

DDRA=0xFF;

PORTA=0XFF;

DDRB=0xFF;

PORTB=0xFF;

TCCR0=0x04;

TIMSK=0x01;

SREG=0x80;

while(1){}

}

interrupt[TIM0_OVF]void timer0_ovf_isr()

{

TCNT0=0x06;

PORTA=BJT[position];

if(position==0)number=sec%10;

if(position==1)number=sec/10;

if(position==2)number=min%10;

if(postion==3)number=min/10;

PORTB=segment[number];

position++;

if(position>3)position=0;

msec++;

if(msec==1000)

{

msec=0;

sec++;

}

if(sec==60)

{

sec=0;

min++;

}

if(min==60)min=0;

}

}

}

int main( void )
{
if
{
        DDRB=0xFF;              /* Make port B as output */

        sei();
        TIMSK=(1<<TOIE0);         /* Enable Timer0 overflow interrupts */
                
        TCNT0 = 0xB2;           /* Load TCNT0, count for 10ms*/
        TCCR0 = (1<<CS02) | (1<<CS00); /* Start timer0 with /1024 prescaler*/
        while(1);
}