[Problem] Interfacing Graphical LCD with AVR

jajoja

hello everyone i really need your help with this one im using a 128x64 lcd module LM12864LFC which is from KS0108 family but i have a problem i cant interface it with for example atmega32 i dont have any idea whats the problem no matter what code i load to my atmega32 nothing is changed it stays as the pic below .
note: for the code i'm using this Guide

pic ( i can adjust the contrast from the variable resistance )

J4D

For starters, very neat work :)

Pin 17 on your LCD should be High at all times, is it low now ?!
I don't have time to read the guide you are following, so if you can tell me how you have the pins setup perhaps i can help you :) look at my Avatar :)

jajoja

yes pin 17 is set high ok
pin1 low
pin2 high
pin3 variable resistance
pin4 ==> pin 20 atmega32
pin5 ==> pin 17 atmega32
pin6 ==> pin5 atmega32
pin7---pin14 ==> pin 22---pin29 atmega32
pin15 ==>pin1 atmega32
pin16 ==> pin2 atmega32
pin17 high
pin18 variable resistance
pin19 high
pin20 low

please help :D

J4D

All is set good, perhaps a programming issue ?!
Check if the following pin setup applies on your side, if not change it to suit this. if it did not work search for another code :)

1 Vss Ground
2 Vcc +5v Supply in
3 V0 Contrast Adjust
4 RS Instruction/Data Register Select PD3
5 R/W READ/WRITE SELECTION PD6
6 E ENABLE SIGNAL PB4
7 DB0 DATA IN/OUT PC0
8 DB1 DATA IN/OUT PC1
9 DB2 DATA IN/OUT PC2
10 DB3 DATA IN/OUT PC3
11 DB4 DATA IN/OUT PC4
12 DB5 DATA IN/OUT PC5
13 DB6 DATA IN/OUT PC6
14 DB7 DATA IN/OUT PC7
15 CS1 Chip Select 1 PB0
16 CS2 Chip Select 2 PB1
17 RST RESET SIGNAL RESET
18 VEE NEGATIVE 10V OUT
19 LED+ LED BACKLIGHT
20 LED- LED BACKLIGHT

jajoja

@j4d if you really understand how to work on lcd's may i ask you to write a simple code that writes hello world on my lcd note: u need to set cs1 and make cs2=0 or vice versa (with the above config) i only need a demo how to power this one

jajoja

yup the hardware side is correct :(

J4D

I code in arduino C, i dont think it is applicable on your side :( what language are you using ?

jajoja

yes same i use c or asm language

J4D

paste your code and let me see.

jajoja

#include <avr/io.h>
#include <util/delay.h>

void Wait()
{
   uint8_t i=0;
   for(;i<23;i++)
      _delay_loop_2(0);
}

void main()
{
   //Set PORTC0 as output

   DDRC=0b00000001;

   while(1)
   {
      //Set PC0=High(+5v)
      PORTC|=0b00000001;
      Wait();

      //Set PC0=Low(GND)
      PORTC&=0b11111110;
      Wait();
   }
}

jajoja

lol as you said its a code problem ill use codevision to try and fix the problem i didnt really read the code but it seems it doesnt have any rd/rw functions or cs1 and 2 :D

arithma

I remember there's a library specifically for this kind of thing. Additionally are you sure the atmega is working correctly? You may need a heartbeat LED to make sure the atmega is fine.
This LCD is hard to get working (while at university I couldn't make it work due to a crystal oscillation setting in a PIC microprocessor (I had no more pins to get a blinking to test)). Your best bet is to get a library and a heart beat. I doubt I'll be more of help, but let me know if it works and how, as I have a little project I may implement sometime soon using the same gadgets you have.

J4D

Ohh my, the code is horrific ! No wonder nothing is coming out from the screen !