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

Offline batch 2 - Kirubhakaran.

Implement a system on the simulator for controlling a DC motor using L293 motor driver, monitor its status and print the running status of motor on the LCD Display.

/*
 * project1.c
 *
 * Created: 25-Nov-22 10:59:46 AM
 * Author : hp
 */ 

#include <avr/io.h>									//avr library
#define F_CPU 16000000L								//CPU Frequency
#include "avr/interrupt.h"							//library to add interrupt
#include <util/delay.h>								//library to give delay

#define direction (PIND&(1<<1))						//direction change switch to D1
#define speed (PIND&(1<<2))							//speed control switch to D2
#define power (PINB&(1<<4))							//Power switch to C3

#define lcdport PORTC								//LCD connected PORTB
#define rs_high() PORTD |= (1<<6);					//object macro for PORTD0 set
#define rs_low() PORTD &= ~(1<<6);					//object macro for PORTD0 reset
#define en_high() PORTD |= (1<<7);					//object macro for PORTD1 set
#define en_low() PORTD &= ~(1<<7);					//object macro for PORTD1 reset
unsigned char i;

void lcd_out(char x,char y,char *str)
{
	cursorpos(x,y);									// to set cursor position
	while(*str)
	{
		lcd_data(*str);								// if string has value it is passed to the data as arg
		str++;
	}
}
void lcd_cmd(unsigned char cmd)
{
	lcdport = cmd;									//send command to the PORTB
	rs_low();										//register low to command mode
	en_high();										//enable high to feed data
	_delay_ms(1);
	en_low();										//enable low to stop transfer
}
void lcd_data(unsigned char data)
{
	lcdport = data;									//send data thru PORTB
	rs_high();										//register high to data mode
	en_high();										//enable high transfer data
	_delay_ms(1);
	en_low();										//enable low to stop transfer
}
void lcd_init()
{
	lcd_cmd(0x38);_delay_ms(5);						//4 bit 2 Lines 5x7 matrix Input
	lcd_cmd(0x02);_delay_ms(5); 					//to return home
	lcd_cmd(0x01);_delay_ms(5); 					//to clear screen
	lcd_cmd(0x0C);_delay_ms(5); 					//to display on and cursor blinking
	lcd_cmd(0x06);_delay_ms(5); 					//to increment cursor
	lcd_cmd(0x80);_delay_ms(5); 					//to cursor begin 1st line
}
void cursorpos(char x,char y)
{
	if ((x<1 || x>2) || (y<1 || y>16))
	{
		x=1;
		y=1;
	}												//gives value if wrong input is given
	if (x==1)
	lcd_cmd(0x7F+y);								//position for first line
	else
	lcd_cmd(0xBF+y);								//position for second line
}
void start()
{
		DDRC = 0xFF;								//enable all PORTC Output pins to interface with LCD 16x2
		DDRA |= ((1<<0)|(1<<1));					//enable A0 and A1 to interface with L293 Motor driver
		DDRD &= ~(1<<1);							//enable D1 as input for direction switch
		DDRD &= ~(1<<2);							//enable D2 as input for speed switch INT0
		DDRB &= ~(1<<3);							//enable B3 as for PWM to the driver
		DDRB &= ~(1<<4);							//enable D4 as input for power switch
		DDRD |= ((1<<6)|(1<<7));					//enable D6 for LCD reset and D7 for LCD enable pin
		PORTD |= (1<<2);							//pullup PORTD2 pin for speed switch
		PORTB |= (1<<4);							//pullup PORTB4 pin for power switch
		
		i=64;										//declare the PWM as 25%
		
		TCCR0 = 0x61;								//non inverting PWM phase correct Mode, no prescaler
		GICR = (1<<INT0);							//enable global interrupt pin INT0
		MCUCR = 0x02;								//enable interrupt negative edge
		
		lcd_init();									//initialise LCD
		
		sei();										//start interrupt
}
int main(void)
{
	start();										//start fn to initialise all the possible pins and ports
	
	while (1)
	{
		while(power == 0)							//if power switch toggled enters the loop
		{
			if(direction==0)						
			{	//initially motor runs in clockwise direction since the pin is pulled up
				PORTA = 0b00000001;
				lcd_out(1,1,"Motor is Running");
				lcd_out(2,3,"  clockwise  ");
			}
			else
			{	//if direction switch pushed motor rotates anticlockwise
				PORTA = 0b00000010;
				lcd_out(1,1,"Motor is Running");
				lcd_out(2,3,"anticlockwise");
			}
			
			OCR0 = i; //sets the pin value incrementing at push using interrupt
		}
		PORTA = 0x00;//if power button is off PORTA is low motor off
		lcd_out(1,1,"  Motor is OFF  ");
		lcd_out(2,3," !!CAUTION!! ");
	}
}
ISR(INT0_vect)
{
	i=i+20;
}//interrupt to increase motor speed every time pushed speed switch connected to INT0 PORTD2