We understand the value of notice boards in public places such as train stations, bus terminals, and airports. Changing notices on a daily basis, however, is a demanding task. This article will show you how to create a GSM-based Wireless Electronic Notice Board. The data we sent from the phone is shown on the LCD by the project.
There are various wireless communication technologies available, such as Bluetooth, RF Connection, ZigBee, and others, but GSM Technology enables for long-range, dependable, and secure communication.
As the name implies, the Wireless Electronic Notice Board utilising GSM project is based on GSM Technology, as mobile phones (which communicate via GSM Technology) have become increasingly common, inexpensive, and simple to use.
NOTE: To send the message (notice), we’ll need a mobile phone, and to receive it, we’ll need a GSM MODEM.
Outline
- Construction and Output Video
- Circuit Principle
- Circuit Diagram of Wireless Electronic Notice Board using GSM
- Components for Wireless Electronic Notice Board using GSM
- Hardware Requirements
- Software Requirements
- Circuit Design
- Circuit Algorithm
- Circuit Simulation Video
- How to Operate Wireless Electronic Notice Board using GSM?
- Circuit Advantages
- Circuit Applications
- Circuit Limitations
- Download Project Code
Construction and Output Video
Circuit Principle
When we send a message from the mobile phone, the message is received by the GSM Modem, which is connected to the Microcontroller and the display unit. The message from the GSM Modem is now read by the microcontroller and shown on the LCD.
When a user sends a message from a mobile phone, the GSM modem transmits the serial command below to signal that a new message has been received.
+CMTI: “SM”,3
The number “3” in the above command denotes the new message’s placement, i.e. it is the third message in the inbox. You must now read this unread message in order for it to appear on the LCD. To read a message from a GSM modem, use the following command.
AT+CMGR=3
The number “3” denotes the location of the message to be read in this case. The GSM module will deliver the following command serially after receiving this command.
+CMGR: “REC UNREAD”,”MD-WAYSMS”,,”13/05/20,15:31:48+34″
Electronics Hub
“REC UNREAD” denotes an unread message, “MD-WAYSMS” denotes the sender’s cell number or name, 13/05/20 denotes the date, 15:31 denotes the time, and Electronics hub denotes the message’s content.
We need to extract the message (Electronics Hub) sent by the user from the above command and display it on the notice board (LCD).
Circuit Diagram of Wireless Electronic Notice Board using GSM
Components for Wireless Electronic Notice Board using GSM
Hardware Requirements
- Microcontroller 8051 (AT89C51)
- Programming board for the 8051 (Programmer with cable)
- Development Board #8051
- GSM MODEM SIM 900A (GSM Module)
- SIM (Simulation Module) Card (for inserting in GSM Modem)
- A mobile phone with a pre-installed SIM card
- LCD Display 16 x 2
- Potentiometer of ten thousandths of a thousandth of a thousandth of
- Wire connections
- Electricity
- If you don’t have access to an 8051 Development Board, you’ll need the following components.
- Resistors: 2 x 10 K (1/4 Watt)
- 2 x 33pF x 2 x 33pF x 2 x Type of Ceramic Disc Capacitors
- 10F / 16V Capacitor with Push Button (Polarized)
- Quartz Crystal, 0592 MHz
Software Requirements
- Vision IDE by Keil (for writing the programme and generating .hex file)
- Willar Software is a software company based in the United (for burning the .hex file in to the microcontroller)
- Proteus is a sea creature that lives in the ocean (for circuit diagram and simulation)
Circuit Design
The Wireless Electronic Notice Board with GSM circuit shown above includes an 8051 microcontroller, a GSM Module (Modem), and a 16 x 2 LCD. The 16 x 2 LCD, which is in 8-bit mode, is utilised to display the message. To display the data, we’ll need eight data lines. The LCD Display’s data lines are connected to the PORT1 pins. P3.6, GND, and P3.7 pins are connected to the control pins RS, RW, and E, respectively.
Because the logic levels of both the GSM Modem and the Microcontroller are already matched in the GSM Module Board, the GSM Module is directly connected to the microcontroller. If the board does not have a level converter, the data must be transferred using a MAX232 level converter as a mediator between the controller and the GSM.
Refer to the Max232 Datasheet for more information.
We must use serial communication to deliver AT commands to the GSM Modem in order to communicate with it (UART protocol). The GSM SIM 900A module is used in this case. The baud rate for this module is 9600.
To learn more about GSM, click here. Read the article GSM Interfacing with the 8051 Microcontroller for more information.
Circuit Algorithm
- Set up the LCD and the UART protocol.
- To determine whether a new message has been received, look for the command +CMTI: “SM”,3 (Location number).
- If the command is received, save the message location number.
- Now read that specific spot and extract the message’s body.
- The message should be displayed on the LCD.
Use below code to display message on LCD wirelessly using GSM
while (rx_data() ! = 0x0d);
while (rx_data() ! = 0x0a);
if (rx_data() == ‘+’)
{
if (rx_data() == ‘C’)
{
if (rx_data() == ‘M’)
{
if (rx_data() == ‘T’)
{
if(rx_data()==’I’)
{
while (rx_data() != ‘,’);
a = rx_data ();
delay_ms (10);
tx_string (“at”);
tx_data (0x0d);
tx_data (0x0a);
tx_string (“at + cmgf =1”);
tx_data (0x0d);
tx_data (0x0a);
tx_string (“at + cmgr =”);
tx_data (a);
tx_data (0x0d);
tx_data (0x0a);
while (rx_data() ! = 0x0a);
while (rx_data() != 0x0a);
while (rx_data() ! = 0x0a);
for (i=0; i<15; i++)
{
read [i]= rx_data();
}
lcd_stringxy(1,0,read);
delay_ms (5000);
}
}
}
}
}
Circuit Simulation Video
How to Operate Wireless Electronic Notice Board using GSM?
- Using Keil software, write the application to the wireless electronic notice board.
- Now, using a hardware programmer and Willar Software, burn the programme to the microcontroller.
- Connect the wires according to the circuit schematic.
- To give 5V DC to the microcontroller, use a power supply circuit.
- Connect the GSM module to the SIM (Subscriber Identity Module).
- Now turn on the power.
- Other mobile phones can be used to send SMS to the GSM module.
- The identical message is now displayed on the LCD.
Circuit Advantages
- Because it is wireless, there are no complicated wires required to display the message on the LCD.
- It uses less energy and is simple to use.
- The circuit can be taken with you.
Circuit Applications
- Used to display messages wirelessly in bus terminals, railway stations, parks, and other locations.
- This project can potentially be used in universities and businesses.
Circuit Limitations
- To receive the message wirelessly, the display unit must have a network.
- Anyone can transmit the message to be displayed because there is no password.
