GSM BASED LCD NOTICE BOARD

DISPLAY

ABSTRACT

• It presents an SMS based notice board incorporating the widely used GSM to facilitate the communication of displaying message on notice board via user’s mobile phone.

• SIM300 GSM modem with a SIM card is interfaced to the ports of the microcontroller with the help of AT commands.

• SIM300 is duly interfaced through a level shifter IC MAX32 to the microcontroller. The messaged is thus fetched into the microcontroller.

• It is further displayed on an electronic notice board which equipped with LCD display interfaced to microprocessor powered by a regulated power supply from mains supply of 230 volts ac.

BLOCK DIAGRAM

COMPONENTS

• Microcontroller (8051)• GSM Modem• SIM• LCD• MAX 232• Power Supply

SOFTWARES

• Keil u Vision • Flash Magic

8051 MICROCONTROLLER

• Microcontroller is a small computer on a single integrated circuit containing a processor core, memory and programmable I/O peripherals.

• The 8051 microcontroller has Harvard architecture with RISC (Reduced Instruction Set Computer) concept.

• The 89C51RB2/RC2/RD2 device contains a non-volatile 16kB/32kB/64kB Flash program memory that is both parallel programmable and serial In-System and In-Application Programmable.

• 8051 has 8-bit ALU which can perform all the 8-bit arithmetic and logical operations in one machine cycle. The ALU is associated with two registers A & B special function registers.

FEATURES

• 4 KB on chip program memory (ROM or EPROM)).

• 128 bytes on chip data memory (RAM).

• 8-bit data bus

• 16-bit address bus

• 32 general purpose registers each of 8 bits

• Two -16 bit timers T0 and T1

• Five Interrupts (3 internal and 2 external).

• Four Parallel ports each of 8-bits (PORT0, PORT1, PORT2, PORT3) with a total of 32 I/O lines.

• One 16-bit program counter and One 16-bit DPTR ( data pointer)

• One 8-bit stack pointer

• One Microsecond instruction cycle with 12 MHz Crystal.

• One full duplex serial communication port.

GSM MODEM

• GSM Modem can accept any GSM network operator SIM card and act just like a mobile phone with its own unique phone number. Advantage of using this modem will be that you can use its RS232 port to communicate and develop embedded applications.

• The modem can either be connected to PC serial port directly or to any microcontroller. It can be used to send and receive SMS or make/receive voice calls.

• It can also be used in GPRS mode to connect to internet and do many applications for data logging and control.

• This GSM modem is a highly flexible plug and play quad band GSM modem for direct and easy integration to RS232 applications.

LCD

• LCD-Liquid Crystal Display is an electronic device for displaying text or characters. We are using 16x2 LCD. It represents 16 characters and 2 line display.

• LCD’s are economical and easily programmable and can easily display special and custom characters.

• In recent years the LCD is finding widespread use replacing LED’s. This is due to the following reasons

1. Declining prices

2. Ability to display numbers, characters and graphics.

3. Incorporation of a refreshing controller into the LCD.

4. Ease of programming.

The standard is referred to as HD44780U, which refers to the controller chip which receives data from an external source (in this case, the 8051) and communicates directly with the LCD.

MAX 232

• converts signals from an RS-232 serial 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.

• The MAX232(A) has two receivers, and two drivers .

DB9 Connector

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

• The DB9 connector is mainly used for serial connections, allowing for the asynchronous transmission of data as provided for standard RS-232 (RS-232C).

CIRCUIT DIAGRAM

FLOWCHART

APPLICATIONS

• The big shops and the shopping centers use digital displays now. • Also, in trains and buses the information like platform number,

ticket information is displayed in digital boards.• In any institution or organization or public utility places like bus

stops, railway stations or parks

CONCLUSION

• The display boards are one of the major communications medium for mass media.

• Local language can be added as a variation in this project. This can be achieved by using graphics and other decoding techniques. Also we realize that this project saves time, energy and hence environment. Cost of printing and photocopying is also reduced as information can be given to a large number of people from our fingertips.

• Thus we can conclude that this project is just a start, an idea to make use of GSM in communications to a next level.

QUERIES

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THANK YOU