AVR TUTORIAL 1

*WAP TO SEND VALUES 00-FF TO PORT B

#include<avr/io.h>

Int main(void)

{

Unsigned char z;

DDRB=0xff;                    //portb is o/p

for(z=0;z<=255;z++)

PORTB=z;

return 0;

}

*WAP TO SEND HEX VALUES FOR ASCII CHARACTERS OF 0,1,2,3,4,5,A,B,C,D TO PORT B

#include <avr/io.h>

Int main(void)

{

Unsigned char myList[]=”012345ABCD”;

Unsigned char z;;

DDRB=0xff;

for(z=0;z<10;z++)

PORTB=myList[z];

while(1);

return 0;

}

*WAP TO TOGGLE ALL BITS OF PORTB 200 TIMES

#include<avr/io.h>

Int main(void)

{

DDRB=0xff;

PORTB=0xaa;

Unsigned char z;

for(z=0;z<200;z++)

PORTB= ~PORTB;

while (1);

return 0;

}

*WAP  TO TOGGLE ALL BITS OF PORTB CONTINUOSLY WITH 100mS DELAY. ASSUME SYS IS ATmega32 WITH XTAL=8MHZ

#include<avr/io.h>

Void delay100ms(void)

{

Unsigned int I;

For(i=0;i<42100;i++);

}

Int main(void)

{

DDRB=0xff;

While(1)

{

PORTA=0xaa;

Delay100ms();

PORTB=0x55;

Delay100ms();

}

Return 0;

}

*WAP TO TOGGLE ALL PINS OF PORTC CONTINUOSLY with 100ms delay. Use predefined function.

#include<avr/io.h>

#define F_CPU 1600000UL

#include<util/delay.h>

Int main(void)

{

DDRC=0xff;

while(1)

{

PORTC=0xff;

_delay_ms(10);

PORTC=0x55;

_delay_ms(10);

_delay_us(1000);

}

return 0;

}

I/O PROGRAMMING

*WAP THAT SHOWS COUNT FROM 0 TO FFH ON LEDS AT PORTB

#include<avr/io.h>

Int main(void)

{

DDRB=0xff;

while(1)

{

PORTB=PORTB+1;

}

return 0;

}

*WAP TO GET A BYTE FROM PORTB AND SEND IT TO PORTC

#include<avr/io.h>

Int main(void)

{

Unsigned char temp;

DDRB=0x00;              //portb is i/p

DDRC=0xff;                //portc is o/p

while(1)

{

Temp=PINB;

PORTC=temp;

}

return 0;

}

*WAP TO TOGGLE ONLY BIT4 OF PORTB CONTINUOSLY WITHOUT DISTURBING THE REST OF THE PINS OF PORTB.

#include<avr/io.h>

Int main(void)

{

DDRB=0xff;

while(1)

{

PORTB=PORTB|0b00010000;      //pin4=1

PORTB=PORTB&0b11101111;     //pin4=0

}

rerurn 0;

}

*A DOOR SENSOR IS CONNECTED TO BIT 1 OF PORTB AND AN LED IS CONNECTED TO BIT7 OF PORTC.WAP TO MONITOR DOOR SENSOR & WHEN IT OPENS, TURN ON THE LED.

#include<avr/io.h>

Int main(void)

{

DDRB=DDRB&0b11111101;     //CHECK

DDRC=DDRC|0b10000000;     //SET

while(1)

{

if(PINB&0b00000010)

PORTC=PORTC|0b10000000;

else

PORTC=PORTC&0b01111111;

}

return 0;

}

BITWISE SHIFT OPERATION IN AVR

Eg: 0b00010000>>3 = 0b00000010(shift right)

       1<<3= 0b00001000(shift left)

*WAP TO MONITOR BIT7 OF PORTB. IF IT IS 1,MAKE BIT4 OF PORTB I/P ELSE CHANGE PIN4 OF PORTB TO O/P.

#include<avr/io.h>

int main(void)

{

DDRB=DDRB&~(1<<7);

while(1)

{

if(PINB &(1<<7))

DDRB=DDRB & ~(1<<4);     //bit4 of b is i/p

else

DDRB=DDRB |(1<<4);       //bit4 of b is o/p

}

return 0;

}

*A DOOR SENSOR IS CONNECTED TO PORTB PIN1, AND AN LED IS CONNECTED TO PORTC PIN7. WAP TO MONITOR THE DOOR SENSOR AND WHEN IT OPENS, TURN ON LED.

#include<avr/io.h>

#define LED 7

#define SENSOR 1

int main(void)

{

DDRB=DDRB &(1<<SENSOR);   //sensor is i/p

DDRC=DDRC |(1<<LED);   //led is o/p

while(1)

{

If(PINB & (1<<SENSOR))    //check sensor pin

PORTC=PORTC|(1<<LED);    //set led pin

else

PORTC=PORTC & ~(1<<LED);       //clear led pin

}

return 0;

}