Design and construction of multi-coloured led scrolling display using pic microcontrollers

This paper develops an easily programmable Light Emitting Diode (LED) based scrolling display. Unlike existing systems, it is designed to display multiple colours writings and alter the characteristics of the message by varying speeds and other properties. Led message scrolling display of multi-colour using microcontroller seeks to develop an information board which could be used everywhere to disseminate information in a more robust and acceptable manner. This work makes use of assembly language as programming language in conjunction with microcontrollers. The circuit was first simulated before carried out actual construction. PIC microcontroller 16F877 was used for this work which has just enough memory space and power for the system is maintained at 12 V which is readily available and hence the whole system can be battery powered so as to cater for power interruption. Testing of the whole design was done using PS2 keyboard port interface in the programming of the display board. The developed system displays 32 letters which can be increased by use of external memory, operates with a 5 v power supply, and has 784 LEDS which are ganged for father viewing distance. This makes a total board size of 0.3 m2