Project 1 - Controlling a DC motor using PWM and monitoring its Running status

code:

#include <avr/io.h>
#define F_CPU 16000000L
#include "avr/interrupt.h"
#include <util/delay.h>
#define sw_dir (PIND & (1<<1))
#define sw_dspd (PIND & (1<<2))
#define pw (PINC & (1<<3))

#define lcd_port PORTB
#define RS_high PORTD |= (1<<5)
#define RS_low PORTD &=~ (1<<5)
#define EN_high PORTD |= (1<<6)
#define EN_low PORTD &=~ (1<<6)
unsigned char i;

void lcd_cmd(char cmd)
{
lcd_port = (cmd & 0xf0);
RS_low;
EN_low;
_delay_ms(1);
EN_high;
lcd_port = ((cmd<<4) & (0xf0));
RS_low;
EN_low;
_delay_ms(1);
EN_high;
}

void lcd_data (char data)
{
lcd_port = (data & 0xf0);
RS_high;
EN_low;
_delay_ms(1);
EN_high;
lcd_port = ((data<<4) & (0xf0));
RS_high;
EN_low;
_delay_ms(1);
EN_high;
}

void lcd_init()
{
lcd_cmd(0x28);
_delay_ms(5);
lcd_cmd(0x02);
_delay_ms(5);
lcd_cmd(0x01);
_delay_ms(5);
lcd_cmd(0x0C);
_delay_ms(5);
lcd_cmd(0x06);
_delay_ms(5);
lcd_cmd(0x80);
_delay_ms(5);
}

void cursorpos(char x,char y)
{
if((x<1 || x>2) || (y>16 || y<1 ))
{
x=1;
y=1;
}
if(x==1)
{
lcd_cmd(0x7F + y);
}
else
{

lcd_cmd(0xBF + y);
}
}

void lcd_out(char x, char y, char *str)
{
cursorpos(x,y);
while(*str)
{
lcd_data(*str);
str++;
}
}

int adc_read(char channel)
{
unsigned int a, result;
ADMUX = channel;
ADCSRA = 0X80;
ADCH = 0X00;
ADCL = 0x00;
ADCSRA |= (1<<6);
while((ADCSRA & 0x40) != 0);
a= ADCL;
result = ADCH;
result = result<<8;
result = result | a ;
return result;
}

int main(void)
{
DDRB = 0XFF;
DDRA |= ((1<<0)| (1<<1));
DDRD &=~ (1<<1);
DDRD &=~ (1<<2);
DDRD |= (1<<5);
DDRD |= (1<<6);
DDRC &=~ (1<<3);
PORTD |= (1<<2);
PORTC |= (1<<3);
i=64;
TCCR0=0X61;
GICR=(1<<INT0);
MCUCR=0X02;
sei();
lcd_init();

while (1)
{
while(pw==0)
{
if(sw_dir == 0)
{
PORTA = 0b00000001;
lcd_out(1,1,"Motor ON- CL ");

}
else
{
PORTA = 0b00000010;
lcd_out(1,1,"Motor ON- ACL");

}
OCR0 = i;

}

PORTA = 0x00;
lcd_out(1,1,"Motor is TURNOFF");
}
}
ISR(INT0_vect)
{
i=i+30;
}

code screenshot:

output circuit diagram: