DTMF based Smart Notice Board System

The mobile phone technology like Dual Tone Multi Frequency (DTMF) and Global System for Mobile communication (GSM) have pushed us to control the things around us with mobile phones and the world is going mobile. Whatever appliances we are dealing with, in our daily life, we want to control them without physically moving to the control unit. As we see in our schools and colleges, we are using manual notice boards that require enough time and man power to change the notices every time we wish to change. As an advancement, the concept of programmable display boards was introduced. But these boards need to be reprogrammed each time. This makes them inefficient for immediate information transfer. In this paper, we have designed a smart notice board by which we can update the notice to be displayed from any part of the world in no time and it is advantageous during emergencies when we want to display alert messages or changed schedule speedily. Our system consists of three main modules viz DTMF module, Liquid Crystal Display (LCD) module, Microcontroller module and a mobile phone attached to display system. The DTMF based smart notice board system can be used at different parts of the city and the messages like Advertisements, News can be instantly displayed and updated. The user presses different numbers which correspond to different dial tones, which are then coded and sent from user mobile phone to display on the system wirelessly and accordingly the stored message for a code is displayed on LCD.