Challenge

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

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.

Program for implementing DC motor along with running status LCD:

#include <avr/io.h>               //including AVR header file
#define F_CPU 16000000L           // the crystal frequency
#include "avr/interrupt.h"        //external interrupt pin header
#include <util/delay.h>           // delay header
#define sw_dir (PIND & (1<<1))    //For direction control d1 pin is declared as push button
#define sw_dspd (PIND & (1<<2))   // For speed control d2 pin is declared as push button for speed control.
#define pw (PINC & (1<<3))        // for power ON/OFF
#define lcd_port PORTB            //PORTB pins are for LCD data
#define RS_high PORTD |= (1<<5)   // Register Select(RS) is high
#define RS_low PORTD &=~ (1<<5)   // RS is low
#define EN_high PORTD |= (1<<6)   //Enable is high
#define EN_low PORTD &=~ (1<<6)   //En is low
unsigned char i;

void lcd_cmd(char cmd)            //command for lcd display
{
	lcd_port = (cmd & 0xf0);      //4 bits for 4 bit LCD mode
	RS_low;
	EN_low;
	_delay_ms(1);                 //delay
	EN_high;                      //enable the lcd by setting high
	lcd_port = ((cmd<<4) & (0xf0)); //lcd port
	RS_low;
	EN_low;
	_delay_ms(1);                //delay
	EN_high;                     //enable the lcd by setting high
}

void lcd_data (char data)       //sending the data to lcd
{
	lcd_port = (data & 0xf0);   //4 bits for 4 bit lcd mode
	RS_high;                    //access data register
	EN_low;
	_delay_ms(1);
	EN_high;
	lcd_port = ((data<<4) & (0xf0)); //4 bits for 4 bit lcd mode
	RS_high;                    //access data register
	EN_low;
	_delay_ms(1);
	EN_high;
}

void lcd_init()
{
	lcd_cmd(0x28);// used for 4 bit lcd mode
	_delay_ms(5);
	lcd_cmd(0x02); // return home
	_delay_ms(5);
	lcd_cmd(0x01); // clear screen
	_delay_ms(5);
	lcd_cmd(0x0C); // display on cursor off
	_delay_ms(5);
	lcd_cmd(0x06); // increment the display cursor
	_delay_ms(5);
	lcd_cmd(0x80); // force cursor to begin from 1st line
	_delay_ms(5);
}

void cursorpos(char x,char y)
{
	if((x<1 || x>2) || (y>16 || y<1 )) //condition will checks the 2 rows and 16 columns
	{
		x=1; 
		y=1; 
	}
	if(x==1)
	{
		lcd_cmd(0x7F + y);            //{ 80-1 = 7F} for starting the 1st line hex decimal value (80) {y we r using the 7F+y means we need to dtart from that column}
	}
	else //(x==2)
	{

		lcd_cmd(0xBF + y);            //{0C-1 = 0B} for starting the 2nd line in 2nd row.
	}
}


void lcd_out(char x, char y, char *str) //here we are checking which position we want to print
{
	cursorpos(x,y);
	while(*str)
	{
		lcd_data(*str);
		str++;
	}
}

int adc_read(char channel)             //  configuring the adc value
{
	unsigned int a, result;
	ADMUX = channel;                   // channel need to select in mux here using 2 bit
	ADCSRA = 0X80;                     //control & status register to enable the adc conversion ,enable the interrupt flag, adc interrupt. ADEN=1
	ADCH = 0X00;                       //clearing the adc register
	ADCL = 0x00;
	ADCSRA |= (1<<6);                  // to start the conversion 6 bit ADSC high
	while((ADCSRA & 0x40) != 0);       // when the conversion become zero means conversion of adc 
	a= ADCL;                           //temp data type a which is stored the ADCL register (ADC0-ADC7)
	result = ADCH;                     // Store the high value (ADC8-ADC9)
	result = result<<8;                //to get proper result or alined value we need to do left shift
	result = result | a ;              // we r adding the ADCL + ADCH to get the 16 bits
	return result;
}

int main(void)
{
	DDRB = 0XFF;                       //Declaring all 8-pins as output.
	DDRA |= ((1<<0)| (1<<1));          //Declaring A0 & A1 pins as output.
	DDRD &=~ (1<<1);                   //Declaring D1 pin as input.
	DDRD &=~ (1<<2);                   //Declaring D2 pin as input.
	DDRD |= (1<<5);                    //Declaring D5 pin as output.
	DDRD |= (1<<6);                    //Declaring D6 pin as output.
	DDRC &=~ (1<<3);                   //Declaring C3 pin as input.
	PORTD |= (1<<2);                   //enabling internal pull up resistor for D2.
	PORTC |= (1<<3);                   //enabling internal pull up resistor for D3.
	i=64;                              //initialize i=64 for 25% duty cycle.(256/4)=64
	TCCR0=0X61;                        //Non-Inverting mode, PWM phase correct mode,NO prescalar.
	GICR=(1<<INT0);                    //using INT0 for interrupt
	MCUCR=0X02;                        //make interrupt negative edge triggered
	sei();                             //Enable global interrupt
	lcd_init();                        //Initialize lcd
	/* Replace with your application code */
	while (1)
	{
		while(pw==0)                    //continue till the push button is released.
		{
			if(sw_dir == 0)             //if the direction control push button is released.
			{
				PORTA = 0b00000001;     // 1 0 to respective 1A 2A pins to rotate in clockwise direction.
				lcd_out(1,1,"Motor ON- CL "); //Running clock wise direction

			}
			else
			{
				PORTA = 0b00000010;     // 1 0 to respective 1A 2A pins to rotate in Anti-Clockwise direction.
				lcd_out(1,1,"Motor ON- ACL");

			}
			OCR0 = i;                   //i increases in ISR, the corresponding value is to be loaded into OCR0.

		}

		PORTA = 0x00;                  //  to Stop rotation.
		lcd_out(1,1,"Motor is TURNOFF");
	}
}
ISR(INT0_vect) //interrupt service routine
{
	i=i+20; // as i increases the duty cycle also increases. i increases by 20 in each push//
	
}

Output:

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