SUMMER TRAINING PRESENTATION

Embedded Systems and Robotics

Prashant Kumar Saini110103134

1. TOOLS AND TECHNOLOGIES USED

1.1 ATMEGA16 MICROCONTROLLER

1.2 LABCENTER PROTEUS

1.3 Code Vision AVR

2. Atmega16 Project: DTMF mobile operated Robot

2.1 Introduction

The invention of this is attributed to Western Electric and

first used by the Bell System in commerce. DTMF signals

are the superposition of 2 sine waves with different

frequencies. It is a signaling Technology used for

communicating between two far away devices. It uses

frequency of speech signals. Only 12 tones are used by our

mobile communication out of the 16 combination that are

possible.

2.2 DTMF tone generation

Pressing the key 1 will result in a sound composed of both a 697 and a 1209 hertz (Hz) tone.

2.3 DTMF Decoder IC: MTT8870

If I am pressing a key let say 1, then it will give the combination of Frequencies 1209 & 697, and this will directly be given to our sound Converter IC, the output of that IC would be 0001(Q1, Q2, Q3, Q4), Following table shows the output for remaining keys.

2.4 Block Diagram of Project

2.5 Circuit ConnectionConnect Q1, Q2, Q3 and Q4 of MT8870 to PA0, PA1, PA2 and PA3 of ATMEGA16.Left motor (-): PC0, Left motor (+): PC1, Right motor (-): PC2, Right motor (+): PC3. 

2.6 Working of Circuit

Connect the cell phone to circuit.

Call the cell phone from a remote phone

Now DTMF tones sent by remote phone to the circuit

The Decoder IC decodes the tone and send equivalent

binary no to the microcontroller.

You will see robot will work according to the program set in

the microcontroller.

2.7 CVAVR Code (Embedded C)

#include<mega16.h>

#include<delay.h>

void main ( ) {

DDRA=0b00000000; // make PORT A as input port

DDRC=0b11111111; // make PORT C as output port

While (1) {

if (PINA==00000010) {

PORTC=0b00001010; // if ‘2’ is pressed then move

forward }

if (PINA==00001000) {

PORTC=0b00000101; // if ‘8’ is pressed then move

backward }

if (PINA==00000100) {

PORTC=0b00000010; // if ‘4’ is pressed then move left }

if (PINA==00000110){

PORTC=0b00001000; // if ‘6’ is pressed then move right }

if (PINA==00000101) {

PORTC=0b00000000; // if ‘5’ is pressed then stop }}}

2.8 Conclusions

Here in this particular project we can also use decoder IC

HT9170 instead of MT8870. Both the ICs are doing same

work of decoding tone

into binary signal. Program can be done in many other ways

as vast varieties of instructions are available. Switch

instruction can also be used. Hence in this way a mobile

controlled robot can be possible using DTMF technique.

2.9 Future Scope

Project can be modified in order to password protect the robot

so that it can be operated only if correct password is entered.

Either cell phone should be password protected or necessary

modification should be made in the assembly language code.

This introduces conditioned access and increase security to

great extent.

 

THANK YOU