The document presents a GSM-based wireless notice board project, detailing its components such as GSM modems, microcontrollers, and LED displays. It includes information about AT commands for operating the modem, circuit diagrams, and the potential applications of the system for various communication needs. Suggestions for improvements and security enhancements are also provided, underscoring the project's adaptability for use in different environments.

1. GSM Based Wireless Notice
Board
Presented By:
Sushant Khajuria
Rajneesh Kumar Salgotra
Kalyan Singh Rathore
under the guidance of
Assoc. prof. A.G.Mir

2. Content
• Block Diagram
• GSM Modem
• AT commands
• LED Display
• Circuit diagram of LED Display
• ATMEGA32
• Serial communication in ATMEGA32
• ULN2003A
• Circuit Diagram of Microcontroller
• Flow Chart
• Conclusion
• Suggestions

3. BLOCK DIAGRAM

4. GSM Modem
• GSM modem is the Data Communicating Equipment which
is connected to terminal equipment for data transmission and
reception.
• GSM stands for Global System for Mobile Communication
• SIM stands for Subscriber identity Module
• GSM modem is controlled using AT commands
• AT stands for Attention
• Ex- AT, AT+CMGR, AT+CMGS, AT+CMGD etc.

5. AT Commands & Corresponding Operation
AT Commands Description
AT To check if Modem is connected
properly
ATE0 To turn echo off
ATE1 To turn echo on
AT+CMGF Set operating Mode

6. AT Commands Description
AT+CMGD= <index>, <delflag> To delete a message
AT+CMGR= <index> To read message from an
index
AT+CMGS= “contact no.” , TP-
type address
To send message to specified
contact no.

7. AT+CMGS command
AT+CMGS = “+0123456789” , 145
> Welcome
Now Press Ctrl+Z
AT+CMGS = “+0123456789” , 145
> Welcome
Now Press Ctrl+Z

8. LED DOT MATRIX DISPLAY
5x7 Dot Matrix Display
• Column Cathode display
• Column Anode Display

9. LED Display
0 1 1 0 0
1
0
0
1
1
1
1

10. LED Display
0 1 1 0 0
1
0
1
1
1
1
1
0 1 1 0 0 0 1 0 0 0
1
0
0
1
1
1
1
1
0
0
1
1
1
1

11. LED Display Bits at columns
Bits
At
Rows

12. Shift Register
ST_CP SH_CP Input Serial Data

13. Circuit Diagram of LED Display

14. Interfacing
• Microcontroller is used to interface one device from
the other

15. Microcontroller ATmega32
Features:
• Advanced RISC Architecture
• High-performance, Low-power Atmel AVR 8-bit Microcontroller
• 32Kbytes of In-System Self-programmable Flash program memory
• 1024Bytes EEPROM
• 2Kbytes Internal SRAM
• Programmable Serial USART
• 32 Programmable I/O Lines
• Full Duplex Serial Line as controller have independent receiver and
transmitter registers.

16. Serial Communication in ATmega32
• ATmega32 is Full-Duplex in serial communication
• UBRR(USART Baud Rate Register)16 bit register is used for setting the
Baud rate
• Out of 16 bits only 12 bits are used for setting the baud rate
• Two shift registers- Transmit shift register and Receive shift register
are used for Full Duplex mode
• Each shift register has its buffer
• These buffers has same I/O address , which is called as UDR(USART
Data register)

17. Serial Communication in Atmega 32

18. ULN 2003A
• ULN2003 is a high voltage and current Darlington array IC
• It contains seven NPN Darlington pairs one for each input
• It is providing current amplification for LED display board
• Collector-Current rating of single darlington pair is 500mA

19. Circuit Diagram of Microcontroller

20. Flow Chart

21. Conclusion
• We can use this Project in college Notice Board, a Professor can send
message for the immediate gathering of students at department.
• It can be used on Highways for traffic control, like traffic on one side
of the road may be blocked in view of VVIP movement or jam ahead
• At Bus Stands, Railway Stations and Airports for the information
about the timing of the Buses , trains and airplanes
• It can be used for crime prevention

22. Suggestion
• The System may be used to authenticate the sender with contact no.
rather than authentication code, so more secure.
• Alarm can be embedded for indication of new message
• Display can be improved with larger size, more brightness