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.

#include  

#define F_CPU 16000000L 

#include "avr/interrupt.h" 

#include  

#define sw_dir (PIND & (1<<1)) // d1 pin is declared as push button for direction control.

#define sw_dspd (PIND & (1<<2)) // d2 pin is declared as push button for speed control.

#define pw (PINC & (1<<3)) // c3 is declared as push button for power ON/OFF

#define lcd_port PORTB //PORTB pins are for LCD data

#define RS_high PORTD |= (1<<5) // d5 pin is used for Register Select(RS)

#define RS_low PORTD &=~ (1<<5) // d5 pin is used for RS

#define EN_high PORTD |= (1<<6) // d6 pin is used for Enable

#define EN_low PORTD &=~ (1<<6) // d6 pin is used for En.

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); //after 1ms disable lcd

       EN_high; //enable the lcd

       lcd_port = ((cmd<<4) & (0xf0)); //lcd port

       RS_low;

       EN_low;

       _delay_ms(1);

       EN_high; //enable the lcd

}

void lcd_data (char data) //send 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 ))

       {

             x=1; //x= row

             y=1; //y= column

       }

       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, 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) // we r configuring the adc value

{

       unsigned int a, result;

       ADMUX = channel; // here we r going to use which channel we 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; // showing the value 0 or clearing the adc register

       ADCL = 0x00; // showing the value 0

       ADCSRA |= (1<<6); 

       while((ADCSRA & 0x40) != 0); // when the conversion become zero means conversion of adc (0x40 means interrupted pin )

       a= ADCL; //dummy data type a and ais 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)); 

       DDRD &=~ (1<<1); 

       DDRD &=~ (1<<2); 

       DDRD |= (1<<5); 

       DDRD |= (1<<6); 

       DDRC &=~ (1<<3); 

       PORTD |= (1<<2); 

       PORTC |= (1<<3);

       i=64; //initializing i=64 because we are running the motor with 25% duty cycle.

       TCCR0=0X61; //Non-Inverting mode, PWM phase correct mode,NO prescalar.

       GICR=(1<

       MCUCR=0X02; //make interrupt negative edge triggered

       sei(); //Enable global interrupt

       lcd_init(); //Initialize lcd

       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 CLockwise dir"); //motor running in clock wise direction

                    }

                    else

                    {

                     PORTA = 0b00000010; // 1 0 to respective 1A 2A pins to rotate in Anti-Clockwise direction.

                      lcd_out(1,1,"AntiColckwise dir");//motor running in anti clock wise direction

                    }

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

             }

             PORTA = 0x00; // 0 0 to respective 1A 2A pins to Stop rotation.

             lcd_out(1,1,"Motor is TURN OFF");

       }

}

ISR(INT0_vect) //interrupt service routine

{

       i=i+20; // as i increases the duty cycle also increases. i increases by 20 in each push and the corresponding value is to be loaded into OCR0 in while loop

}