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

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.

BLOCK DIAGRAM TRANSMITTER:

RECEIVER

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

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.

EMBEDDED SYSTEMS

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 11.0592MHZ 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

PIN DIAGRAM OF AT89S52

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

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

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 : 433.92 MHz TX Supply Voltage : 3V ~ 6V TX Out Put Power : 4 ~ 12 Dbm

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.

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.

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)

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

KEIL COMPILER WINDOW

BIBILOGRAPHY The 8051 Microcontroller and Embedded systems” by Muhammad Ali Mazidi and Janice Gillispie Mazidi , Pearson Education. ATMEL 89S52 Data Sheets. www.atmel.com www.beyondlogic.org www.wikipedia.org www.howstuffworks.com www.alldatasheets.com

THANK ‘Q’