Lumos

This dev. Board contains- .ATMega-8 microcontroller .L293D H-Bridge motor driver

LUMOS


Development Board Used


SENSORS

3 LDR sensors have been used for detection of light sources.

With the change in the intensity of light, the voltage drop across the

LDR changes.

But the voltage generated by the LDR is analog.So we must obtain the

corresponding digital value of the voltage drop,resulting due to a

change in the intensity of light sources.

For this,we may use a comparator IC which gives digital HIGH and

digital LOW output.

Here, we are using LM324 for the same.







Circuit diagram


Pins 1,7 and 8 can be used for digital outputs.

The digital outputs obtained from the comparator are given to the

microcontroller.

Here we have used PD5,PD6 and PD7 as the input pins of the

microcontroller.

PB1,PB2,PB3 and PB4 have been used as the output pins of the

microcontroller. These ports are internally connected to the H-Bridge IC

at the dev. Board.

PROGRAM We have used Embedded C for writing program for the task.

#include<avr/io.h>

#include<util/delay.h>

void main()

{

DDRD=0b00000000; //set PORTD as input port for LDR sensors

DDRB=0b00011110; //PB1, PB2, PB3, PB4 as output port

int ls=0,cs=0,rs=0;

while(1)

{

ls=(PIND&0b01000000); //set PD6 for left LDR sensors

rs=(PIND&0b10000000); //set PD7 for right LDR sensors

cs=(PIND&0b00100000); //set PD5 for center LDR sensors

if((ls==0b00000000)&(cs==0b00000000)&(rs==0b00000000))// cs and rs& ls oFF

{

PORTB=0b00010000;//go RIGHT


ls=0;

rs=0;

cs=0;

}

if((ls==0b00000000)&(cs==0b00000000)&(rs==0b10000000))//Rs on

{


ls=0;

rs=0;

cs=0;

}

if((ls==0b00000000)&(cs==0b00100000)&(rs==0b00000000))//Cs on

{

PORTB=0b00010010;//GO STRAIGHT

ls=0;

rs=0;

cs=0;

}

if((ls==0b00000000)&(cs==0b00100000)&(rs==0b10000000))// cs and Rs on

{


ls=0;

rs=0;

cs=0;

}

if((ls==0b01000000)&(cs==0b00000000)&(rs==0b00000000))//ls on

{

PORTB=0b00000010;//turn left


ls=0;

rs=0;

cs=0;

}

if((ls==0b01000000)&(cs==0b00000000)&(rs==0b10000000))//rs and ls on

{


ls=0;

rs=0;

cs=0;

}

if((ls==0b01000000)&(cs==0b00100000)&(rs==0b00000000))//ls and Cs on

{


ls=0;

rs=0;

cs=0;

}

if((ls==0b01000000)&(cs==0b00100000)&(rs==0b10000000))//all oN

{

PORTB=0b00010010;//STRAIGHT

ls=0;

rs=0;

cs=0;

}

}

}



Points scored

1st Run

T=1;

R=1;

2nd Run

S=5;

Total time=300 s

Run time=58 s.

=>B=121;

D=1;

T=2;

Final score=871.


-Here Goes Our Bot “LU32”-

Developed BY-

Shubham Kumar,MD. Saeed, Dishant Akshay, Feroz Khan

IIT KGP

2nd

Feb 2013

Documents

Lumos