1.     GLCD (Graphical Liquid Crystal Display)

The Graphics LCD as the name suggests is a type of LCD which can display graphics. The graphical representation of any data presents good understanding than just characters. More user friendly applications can be designed by using the graphical LCDs.

       1.1    Interfacing GLCD

Mentioned schematic shows how to interface the GLCD to micro controller. The 128X64 Graphical LCD interfaces to adjust contrast through trim pot. The GLCD needed to create 8-bit interface; 8 data bits (D0 – D7), three control lines, address bit (RS), read/write bit (R/W) and control signal (E), Page Select (CS).

2.    Switch

A switch is an electrical component that can break an electrical circuit, interrupting the current or diverting it from one conductor to another. A switch may be directly manipulated by a human as a control signal to a system, or to control power flow in a circuit.

     2.1    Interfacing Switch

Schematic shows how to interface the switch to micro controller. A simple switch has an open state and closed state. However, a micro controller needs to see a definite high or low voltage level at a digital input. A switch requires a pull-up or pull-down resistor to produce a definite high or low voltage when it is open or closed. A resistor placed between a digital input and the supply voltage is called a "pull-up" resistor because it normally pulls the pin's voltage up to the supply.

3.     Game algorithm

The display is virtually divided into 3 columns. And in each column there will be some  moving obstacles coming from top towards bottom. The appearance of the obstacles will be totally random in nature and for the 3 columns there will be three switches and to eliminate an obstacle one need to press the corresponding switch before the obstacle touches the bottom boundary.  If the obstacle touches the bottom, the game will be over.

Also there are some extra features like level up , pause, life and score display.