1. SUBMITTED BY EDGEFX TEAM
PORTABLE CODED WIRELESS MESSAGE COMMUNICATION BETWEEN TWO PARTIES SECRETLY WITH LCD DISPLAY
SUBMITTED BY
EDGEFX TEAM

2. ABSTRACT
The outline of the project is that the text message is encrypted by using the Microcontroller and the encrypted message is transmitted through wireless using Radio frequency transmitting Module.
At the receiver end the signal is received by the standard RF receiver and the analog signal is converted to digital form and is fed to the Microcontroller and it is decrypted by the Microcontroller and the message is displayed over the LCD display.

3. BLOCK DIAGRAM
TRANSMITTER:

4. RECEIVER

5. HARD WARE EQUIPMENTS POWER SUPPLY BLOCK
MICROCONTROLLER (AT89S52/AT89C51)
RF MODULE(RX & TX)
LCD
IN4007
LED
RESISTORS
CAPACITORS

7. EMBEDDED SYSTEMS Definition for :- EMBEDDED SYSTEMS
A combination of hardware and software which together
form a component of a larger machine.
An example of an embedded system is a microprocessor that
controls an automobile engine.
An embedded system is designed to run on its own without
human intervention, and may be required to respond to
events in real time.

8. EMBEDDED SYSTEMS

9. AT89S52 MICRO CONTROLLER Compatible with MCS®-51 Products
8K Bytes of In-System Programmable (ISP) Flash Memory
4.0V to 5.5V Operating Range
Crystal Frequency MHZ
Three-level Program Memory Lock
256 x 8-bit Internal RAM
32 Programmable I/O Lines
Three 16-bit Timer/Counters
Eight Interrupt Sources
Full Duplex UART Serial Channel
Watchdog Timer
AT89S52

10. PIN DIAGRAM OF AT89S52

11. LED LEDs are semiconductor devices are made out of silicon
When current passes through the LED, it emits photons as a byproduct. Normal light bulbs produce light by heating a metal filament until its white hot
LEDs present many advantages over traditional light sources including lower energy consumption, longer lifetime, improved robustness, smaller size and faster switching

12. RF remote control The circuit uses HT 12E, HT 12D encoder and decoder.
433MHz ASK transmitter and receiver is used for the remote control.

13. Features of RF Range in open space(Standard Conditions) : 100 Meters
RX Receiver Frequency : 433 MHz
RX Typical Sensitivity : 105 Dbm
RX Supply Current : 3.5 mA
RX IF Frequency : 1MHz
Low Power Consumption
Easy For Application
RX Operating Voltage : 5V
TX Frequency Range : MHz
TX Supply Voltage : 3V ~ 6V
TX Out Put Power : 4 ~ 12 Dbm

14. RF Encoder & Decoder
The HT 12E Encoder ICs are series of CMOS LSIs for Remote Control system applications. They are capable of Encoding 12 bit of information which consists of N address bits and 12-N data bits.
The HT 12D ICs are series of CMOS LSIs for remote control system applications.
This ICs are paired with each other. For proper operation a pair of encoder/decoder with the same number of address and data format should be selected.
The Decoder receive the serial address and data from its corresponding decoder, transmitted by a carrier using an RF transmission medium and gives output to the output pins after processing the data.

15. LIQUID CRYSTAL DISPLAY (LCD)
Most common LCDs connected to the microcontrollers are 16x2 and
20x2 displays.
This means 16 characters per line by 2 lines and 20 characters per line
by 2 lines, respectively.
The standard is referred to as HD44780U, which refers to the controller
chip which receives data from an external source (and communicates
directly with the LCD.

16. LCD BACKGROUND
If an 8-bit data bus is used the LCD will require 11 data lines
(3 control lines plus the 8 lines for the data bus)
The three control lines are referred to as EN, RS, and RW
EN=Enable (used to tell the LCD that you are sending it data)
RS=Register Select (When RS is low (0), data is treated as a command)
(When RS is High(1), data being sent is text data )
R/W=Read/Write (When RW is low (0), the data written to the LCD)
(When RW is low (0), the data reading to the LCD)

17. SOFTWARE REQUIREMENTS
PROGRAMMING LANGUAGES Embedded C , ALP (Assembly Language) COMPILERS: Keil 2.0/3.0uv DUMPING SOFT WARE: Using Micro controller flash Software we are dumping our HEX Code into Micro Controller

18. KEIL COMPILER WINDOW

19. BIBILOGRAPHY
The Microcontroller and Embedded systems” by Muhammad Ali Mazidi and Janice Gillispie Mazidi , Pearson Education.
ATMEL 89S52 Data Sheets.

20. THANK ‘Q’