This presentation shows Dual tone multi frequency mobile operated robot. CVAVR code is also provided....

1. SUMMER TRAINING
PRESENTATION
Embedded Systems and Robotics
Prashant Kumar Saini
110103134

2. 1. TOOLS AND TECHNOLOGIES USED
1.1 ATMEGA16 MICROCONTROLLER

3. 1.2 LABCENTER PROTEUS

4. 1.3 Code Vision AVR

5. 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.

6. 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.

7. 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.

8. 2.4 Block Diagram of Project
2.5 Circuit Connection
Connect 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.

9. 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

10. 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

11. 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.

12. THANK
YOU