Atmega32Timer1InterruptExample.c

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

#define LED PD4

ISR (TIMER1_OVF_vect)    // Timer1 ISR
{
	PORTD ^= (1 << LED);	
	TCNT1 = 63974;   // for 1 sec at 16 MHz
}

int main()
{
	DDRD = (0x01 << LED);     //Configure the PORTD4 as output
	
	TCNT1 = 63974;   // for 1 sec at 16 MHz	

	TCCR1A = 0x00;
	TCCR1B = (1<<CS10) | (1<<CS12);;  // Timer mode with 1024 prescler
	TIMSK = (1 << TOIE1) ;   // Enable timer1 overflow interrupt(TOIE1)
	sei();        // Enable global interrupts by setting global interrupt enable bit in SREG
	
	while(1)
	{
		
	}
}

1. On line 1 and 2 it would be nicer to add a space between '#include' and '<'
2. On line 19 the second semicolomn should be removed.
3. On line 20 it would be nicer te remove the space before the semicolomn.

It looks like the TCNT1 value you are setting is not quite correct for the comment.

1. On line 9 it should be "// for 0.1 sec at 16 MHz" instead of "1 sec".
2. On line 16 it should be "// for 0.1 sec at 16 MHz" instead of "1 sec".