Graphic LCD

Graphic  LCD

Character LCD                                                     

GraphicLCD

The character LCD can display only
characters, but what if we want to display any customized character or images? Well in order to display that we need graphic LCD.  Graphic LCDs are used in many applications like mobile phones, video game and display units etc. A very common graphic LCD is JHD12864E  this LCD has a display format of 128x64 dots and has yellow and green back light which is commonly used in embedded systems as display unit.

 This LCD display layout is vertically divided in to two parts called Chip 1 and Chip 2, each part is controlled by a separate KS0108 controllers and controller is selected by chip select pin (CS). The display is also  divided horizontally in to 8 sections called pages (page 0 through page 7), each page is again divided in to strips, one strip is 8 pixels. This can be easily understood from the following figure.

Single page

          

Each page has 64 strips. Then the total number of strips is 128 X 8 = 1024

Each strip consists of 8 pixels or dotes so that total number of pixels in whole LCD is 1024 X 8 = 8192.  When we write program to display anything on LCD what we actually does is, we just darken or lighten the pixel.

Power Supply connection

Pin out

Block diagram