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GSM BASED DIGITAL NOTICE BOARD
INTRODUCTION
The user sends a SMS containing the data to be rolled.
PC receives the SMS and send it to both the slaves via RS232 -RS485 converter section.
Both the slaves receive the frame. Then they match the slave ID in the frame to their own ID’s.
If ID match occurs then that particular slave rolls the data on it’s alphanumeric display.
GSM BASED DIGITAL NOTICE BOARD
BLOCK DIAGRAM
COMPONENTS USED
Microcontroller PIC( 16F877A).
RS 232 and 485 Transreceivers.
Octal Bus Transreceivers (74LS245).
Alphanumeric Display.
GSM Module.
3:8 Decoder.
SPECIFICATIONS OF COMPONENTS
PIC µC 16F877A
I\O ports: 5
Operating frequency: 20 MHz
Flash memory : 8Kb
EEPROM data memory: 256 bytes
Interrupt capability (up to 14 sources)
Serial communication:MSSP, USART
Parallel communicationSP
Instruction Set:35 instructions
PIN DIAGRAM
RS 485
Long distance communication
Serial communication standard
Thermal shutdown protection
Allowing up to 32 transceivers on the bus
Supply voltage : 5V
DB-9 CONNECTORS
FEMALE CONNECTOR
MALE CONNECTOR
PIC µC WITH OCTAL BUS TRANSCEIVERS
PIC INTERFACE WITH RS 485
ALPHANUMERIC DISPLAY
1.5 “ Display.
5Volts operation.
Common anode mode.
100 mA current operation.
0.5W power consumption.
DISPLAY SELECTION 3:8 DECODER IC
DIGITAL NOTICE BOARD
GSM MODULE
Ultra small size.
Light weight (3.2 g).
Easy to integrate.
Low power consumption.
Full RS232 on CMOS level with flow control
High performance on low price.
SOFTWARE OVERVIEW
Express PCB to draw PCB layout.
Programming of PIC using ‘ASSEMBLY’ in
KEIL Software.
Programming at Base Station using Visual
Basic (VB-6.0).
VB INTERFACE WINDOW
PCB LAYOUT
ADVANTAGES
Easy to implement.
More reliable.
Secured data transfer.
Can be used in places where human beings can not work.
Robust system.
High accuracy because of sensors and microcontroller.
APPLICATIONS
This system can be used in:
Cities, Malls, Theaters.
In Industrial Buildings.
In Remote and Rural Areas.
In Trains And Busses.
In Many Institutions For Information Purposes.
FUTURE ENHANCEMENT
Higher end controller can be used ARM-9.
Announciator system cab be added.
Increase the no. of slaves.
Use of satellite technology instead of GSM.
Access the data stored in dedicated PC.