ZIGBEE NOTICE BOARD

Presented By:Yash Shah(D.J.S.C.O.E.)

Zarna Parekh(D.J.S.C.O.E.)

Hansal Shah(D.J.S.C.O.E.)

Guided by :Prof.Ninad Mehendale

• Wireless board• Message sent by the PC is transmitted

through Xbee at free of cost and displayed on Graphic LCD.

• Range of Xbee is 300-400m.

Abstract

Introduction• Advanced hi-tech notice board.• Information transmitted at a much faster rate.• Interfacing a display with microcontroller and

updating the data to be displayed using a zigbee module.

• Zigbee is a low power wireless technology.

What is ZigBee?• ZigBee is a technology of data transfer in

wireless networks.• Zigbee is a PAN technology based on the IEEE

802.15.4 standard.• ZigBee devices have the ability to form mesh

networks between nodes, which can be expanded and multiplied in order to cover larger area.

• It has low energy consumption and is designed for multi-channel control systems, alarm systems, and lighting control.

• It also has various home and industry applications.

Characteristics of Zigbee

• Low power consumption• Small size, light weight• Ease of implementation• Reliable data transfer• Appropriate level Security• Low cost• Fast acquisition time• Data rates of 250 kbps (@ 2.4GHz), 40 kbps

(@915 MHz) and 20 kbps (@ 868MHz )

Standard Xbee Protocol

• Frequency: 2.4 GHz• Power Output: 1mW• Maximum Range: 90m• RF data rate: 250 kbps

Working Of Hardware• Microcontroller ATMEGA8

of 8KB memory.• Crystal oscillator of 16MHz.• Pull up resistor of 10 KΩ.• Xbee module for reception

and transmission of data.• GLCD is used 128 x 64 pixels• Transmitting via USB port to

RS232 port connected to Xbee module

• Xbee is transmitting at PAN ID 31 and baud rate of 115200 to other Xbee.

Image Black & White 128 x 64 pixels

Colour to Gray Scale

Conversion Of Coloured To Black & White Image

• MATLAB program reads the image.• If it is coloured, the image will be converted to

Gray scale and eventually to Black & White.

Gray Scale: 0-255Greater than 128 = 1Less than 128 = 0

Coloured to Black & White

Start

Read data from Xbee

Is any new data

Refresh GLCD

Stop

No

Yes

Flowchart Of Microcontroller

Algorithm Of Microcontroller

• Start• Read data from Xbee• Checks if any new data is there• If yes Refresh GLCD else read for new data

from Xbee• After refreshing the GLCD it will again

check for new data and this process continues.

Start

Read Image (B)

Is imagecolour

Convert to Black and White

Convert to Gray Scale

Flowchart Of MATLAB Programming

A

Yes

No

Is size greater than or less than or equal to 128 x 64

A

Enlarge Shrink

Transmit to USBCom Port

Is end of Program

Stop

B

Less

Equal

Greater

Yes

No

Algorithm Of MATLAB Programming• The program will read the image.• Check whether the image is coloured.• If yes, it will convert to Gray Scale and then to

Black & White or else directly to Black & White.• It then checks for the size, if it is greater than

128x64 it will shrink the image and if its less than 128x64 it will enlarge.

• The image is transmitted to USB COM port.• It will check for the last image, if it is the last

image it will end the program or else will read a new image

Advantages

• Low cost.• Secured data.• Wireless communication.• Recovery of data after power failure.• Energy efficient.• Fast since only white and black

Disadvantages

• Limited range.• Costly compared to black board.• PC Dependant• Small LCD size 128*64• Black and white only

Application• At schools, colleges for displaying

assignments. • Public places, hospitals, government offices

etc.

ANY QUESTION