1. EMBEDDED SYSTEMS TUTORIAL 9- INTERFACING 128X64
GRAPHICAL LCD WITH AVR
Hi friends this time I am here with a very interesting embedded systems tutorial, as in last tutorials we
learnt about 16x2 LCD interfacing but some times it seems vey difficult to display a huge amount of data
on such a small space provided by 16x2 LCD , so there is the solution a powerful 128x64 GRAPHICAL
LCD, with a lot of space and facility to display graphics along with alphanumeric data, in this tutorial we
are going to learn how to interface a GRAPHICAL LCD with AVR. We are going to discuss about a
ks0108 based LCD interfacing.
What is required??
I am using a HQM1286404 LCD it’s a pretty old one and please don’t be mistaken with newer versions of
LCD, if you are using any other version you have to find its datasheet for wiring connections because
wiring connections may be different from version to version. I will provide connections for HQM1286404
LCD only and its pretty hard to get accurate wiring connection , so better consult your datasheet and
internet as well. Except this you will need a AVR MCU, I am using ATMEGA 8 here and of course an LCD
library you can find o many libraries on internet but I am giving a best link to download a very nice library
written by Mr. Fabian Maximilian Thiele , thanx to him the link for this library is GLCD_LIBRARY
LCD PIN-OUT CONNECTIONS
Here is the correct pin-out of LCD:
1 Vcc
2 GND
3 VCON
4-11 DB0-DB7

2. 12 CS2
13 CS1
14 RESET
15 R/W
16 D/I
17 EN
18 Vee out
19 LED Anode
20 LED Kathode
NOTE:- in some cases you will found that your LCD screen is swapped into two halves in such cases just
swap the chip select pins and problem will be corrected...:)
LIBRARY USE
The library , which you have downloaded contains to files ks0108.c and ks0108.h you have to copy
these files and have to paste in the same folder wher .c file of your main program is contained and you
have to add corresponding header files in the beginning of the program too like
#include "ks0108.h"
#include "ks0108.c"
the .h files contains the information about pin connection and commands you can easily change the
connection pin and ports from there .
Getting familiar with commands is just a learning by doing thig more you do more you learn. Just go
through the library to know more about the command its self explaining.
Along with these library files some font files are also provided these fonts must be added by adding
corresponding header file in beginning of the program.except these font you can fetch your windows font
with the help of this java program GLCDFontCreator2
SOURCE CODE
here is an interesting source code to start with
#include <inttypes.h>
#include <avr/io.h>
#include <avr/pgmspace.h>
#include "ks0108.h"
#include "ks0108.c"
#include "arial_bold_14.h"
int main(void) {
// Wait a little while the display starts up
for(volatile uint16_t i=0; i<15000; i++);
// Initialize the LCD

3. ks0108Init(0);
// Select a font
ks0108SelectFont(Arial_Bold_14, ks0108ReadFontData, BLACK);
// Set a position
ks0108GotoXY(15,10);
// Print some text
ks0108Puts_P(PSTR("Tech_strong"));
// two little circles
ks0108DrawCircle(30, 30, 5, BLACK);
ks0108DrawCircle(90, 30, 5, BLACK);
// again some text
ks0108GotoXY(29,38);
ks0108Puts_P(PSTR("Tutorials"));
// a loading bar
for(int x=0;x<128;x++)
{
ks0108GotoXY(x,50);
ks0108DrawRect(x, 50, 80, 10, BLACK);
}
while(1);
}
CIRCUIT DIAGRAM
now just implement this easy circuit burn your MCU with corresponding .hex file and enjoy your
GRAPHICAL lcd.

4. NOTE:- In my program I have changed data port of LCD from PORTA to PORTD so be careful if
you are using this circuit connection you will have to change PORTA to PORTD in ks0108.h file of
library be careful ….!!
I think it was a useful article for you all in case of any query, doubt or critical view just leave a comment in
next tutorial we will discuss about displaying an image on this LCD,… till then bye…!