Project 1 - Controlling a DC motor using PWM and monitoring its Running status
#include
#define F_CPU 16000000L // define the crystal frequency
#include "avr/interrupt.h" // we are using external interrupt pin
#include
#define sw_dir (PIND & (1<<1>
#define sw_dspd (PIND & (1<<2>
#define pw (PINC & (1<<3>
#define lcd_port PORTB //PORTB pins are for LCD data
#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) //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>
RS_low;
EN_low;
_delay_ms(1); //after 1ms disable lcd
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>
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>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>
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>
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 /* 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; // 0 0 to respective 1A 2A pins 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// // and the corresponding value is to be loaded into OCR0 in while loop// }