WIRELESS NETWORKING OF DEDICATED COMPUTERS Under the Guidance of Submitted by

ABSTRACT The term wireless networking refers to technology that enables two or more computers to communicate using standard network protocols, but without network cabling. In this project we use a pair of 2.4 GHz transreceiver modules used for bidirectional chat communication from one PC to another wirelessly. A 555 timer is used in monostable mode which drivers a buzzer to indicate that a data is received on PC drawing the attention to respond to the caller.

BLOCK DIAGRAM

HARDWARE REQUIREMENTS TRANSFORMER (230 – 12 V AC) VOLTAGE REGULATOR (LM 7805) RECTIFIER FILTER TRANSRECEIVER MODULE 555 TIMER BC547 BUZZER MAX232 IN4007 LED RESISTORS CAPACITORS

POWER SUPPLY Bridge rectifier 5v Regulator 230 V AC 50 Hz 5V DC Filter(470µf) 12V step down transformer

MAX 232 The MAX232 is an integrated circuit that converts signals from an RS-232serial port to signals suitable for use in TTL compatible digital logic circuits. The MAX232 is a dual driver/receiver and typically converts the RX, TX, CTS and RTS signals . When a MAX232 IC receives a TTL level to convert, it changes a TTL Logic 0 to between +3 and +15V, and changes TTL Logic 1 to between -3 to -15V, and vice versa for converting from RS232 to TTL.

DB9 CONNECTOR The DB9 (originally DE-9) connector is an analog 9-pin plug of the D-Sub miniature connector family (D-Sub or Sub-D).

555 TIMER The 555 Timer IC is an integrated circuit (chip) implementing a variety of timer and multivibrator applications. The original name was the SE555 (metal can)/NE555 (plastic DIP) and the part was described as "The IC Time Machine". Depending on the manufacturer, the standard 555 package includes over 20 transistors, 2 diodes and 15 resistorson a silicon chip installed in an 8-pin mini dual-in-line package (DIP-8)

PIN DIAGRAM OF 555 The 555 timer IC is a simple 8 pin DIL package IC. It can: be used as a monostable be used as an astable source or sink 100mA use supply voltages of 5v to 15v disrupt the power supply - use a decoupling capacitor!

PC COMMUNICATION

Plug-and-communicate (no configuration required) Transparent operation supports existing software & systems Simple configuration using software & standard AT commands Retries & acknowledgements for guaranteed packet delivery RS-232/422/485 protocol & multi-drop bus support Peer-to-peer, point-to-point & point-to-multipoint networks

THANK ‘Q’