Challenge

Project 2 - Measuring distance of an object using ultrasonic sensor (HC-SR04)

NNandhini M24 Sept 2022

OFFLINE

#include

#define F_CPU 8000000

#include

#define LCD_data_dir DDRD //LCD data port direction

#define LCD_cmd_dir DDRC //LCD command port direction register

#define LCD_data_port PORTD //LCD data port

#define LCD_cmd_port PORTC //LCD command port

#define EN PC2 //enable signal pin

#define RW PC3 //read/write signal pin

#define RS PC4 //register select signal pin

void LCD_cmd(char); //command write fn declaration

void LCD_char(char); //LCD data write fn

void LCD_init(void); //LCD initialise function

void LCD_string(char*); //send string to LCD fn

void LCD_string_xy(char,char,char*); //sending row,position and string to LCD fn

void LCD_cmd(char cmd)

{

LCD_data_port=cmd; //command data to LCD data port

LCD_cmd_port&=~((1<RW)); //Making RS and RW low

LCD_cmd_port|=(1<

_delay_ms(1);

LCD_cmd_port&=~(1<

_delay_ms(3);

}

void LCD_char(char char_data) //LCD data write function

{

LCD_data_port=char_data; //writing data to LCD data port

LCD_cmd_port&=~(1<

LCD_cmd_port|=(1< //high to low transition on EN, RS high

_delay_ms(1);

LCD_cmd_port&=~(1<

_delay_ms(1);

}

void LCD_init(void)

{

LCD_cmd_dir|=(1<1<

LCD_data_dir=0xff; //LCD data port direction as output

_delay_ms(20);

LCD_cmd(0X38);_delay_ms(5); //2line and 5X7 matrix

LCD_cmd(0X02);_delay_ms(5); //

LCD_cmd(0X01);_delay_ms(5); //clear LCD command

LCD_cmd(0X0C);_delay_ms(5); //display on, cursor off command

LCD_cmd(0X06);_delay_ms(5); //increment cursor automatically

LCD_cmd(0X80);_delay_ms(5); //8is for first line&0 denotes the zero position

}

void LCD_string(char* str)

{

int i;

for(i=0;str[i]!=0;i++) //string will be sent till it reaches NULL

{

LCD_char(str[i]);

}

void LCD_string_xy(char row,char pos,char *str)

{

if(row==1)

LCD_cmd((pos&0x0f)|0x80); //first row and position<16

else if(row==2)

LCD_cmd((pos&0x0f)|0xC0); //second row and position<16

LCD_string(str); //LCD string function called

}

#define Trigger_pin PA0 //trigger pin

int TimeOverflow=0;

ISR(TIMER0_OVF_vect)

{

TimeOverflow++; //increment the timer overflow

}

int main(void)

{

char string[10];

long count;

double distance;

DDRA=0X01; //Trigger point as output

PORTB=0xff; //turn on pull up

LCD_init();

LCD_string_xy(1,0,"Ultrsonic");

sei(); //set global interrupt

TIMSK=(1<

TCCR1A=0;

while (1)

{

PORTA|=(1<

_delay_ms(10);

PORTA&=(~(1<

TCNT1=0; //clear timer counter

TCCR1B=0x41; //no prescalar,capture on rising edge

TIFR=1<

/*calculating width of echo by input capture(ICP)*/

while ((TIFR & (1 << ICF1)) == 0); // Wait for rising edge

TCNT1 = 0; // Clear Timer counter

TCCR1B = 0x01; // Capture on falling edge, No prescaler

TIFR = 1<

TimeOverflow = 0; // Clear Timer overflow count

while ((TIFR & (1 << ICF1)) == 0); // Wait for falling edge

count = ICR1 + (65535 * TimeOverflow); // Take count

/* 8MHz Timer freq, sound speed =343 m/s */

distance = (double)count / 466.47;

dtostrf(distance,2,2,string); // distance to string

strcat(string,"cm"); // Concatenation unit i.e.cm

LCD_string_xy(2,0,"Dist = ");

LCD_string_xy(2,7,string); // Print distance

_delay_ms(200);

}

Project 2 - Measuring distance of an object using ultrasonic sensor (HC-SR04)

Ship work like this
in your own course.

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Ship work like thisin your own course.

Talk to a career counsellor

Ship work like this
in your own course.