LCD EA DIP204-4 Display KS0073Controller

Hi everyone, please help me.
I`m using arduino MEGA and trying to interface it with LCD EA DIP204-4 Display which use KS0073 Controller. I have read many things in this forum about how to interface with LCD. My Aim is to interface it with 4bit(save pins).

Here is my library & COde:

#include “LCD4Bit.h”
extern “C” {
#include <stdio.h> //not needed yet
#include <string.h> //needed for strlen()
#include <inttypes.h>
#include “WConstants.h” //all things wiring / arduino

//command bytes for LCD
#define CMD_CLR 0x01
#define CMD_RIGHT 0x1C
#define CMD_LEFT 0x18
#define CMD_HOME 0x02

// --------- PINS -------------------------------------
//is the RW pin of the LCD under our control? If we’re only ever going to write to the LCD, we can use one less microcontroller pin, and just tie the LCD pin to the necessary signal, high or low.
//this stops us sending signals to the RW pin if it isn’t being used.
int USING_RW = false;

//RS, RW and Enable can be set to whatever you like
int RS = 12;
int RW = 1;
int Enable = 11;
//DB should be an unseparated group of pins - because of lazy coding in pushNibble()
int DB = {2, 3, 4, 5}; //wire these to DB4~7 on LCD.


//how many lines has the LCD? (don’t change here - specify on calling constructor)
int g_num_lines = 2;

//pulse the Enable pin high (for a microsecond).
//This clocks whatever command or data is in DB4~7 into the LCD controller.
void LCD4Bit::pulseEnablePin(){
// send a pulse to enable
delay(50); // pause 1 ms. TODO: what delay, if any, is necessary here?

//push a nibble of data through the the LCD’s DB4~7 pins, clocking with the Enable pin.
//We don’t care what RS and RW are, here.
void LCD4Bit::pushNibble(int value){
int val_nibble= value & 0x0F; //clean the value. (unnecessary)

for (int i=DB[0]; i <= DB[3]; i++) {
digitalWrite(i,val_nibble & 01);
val_nibble >>= 1;

//push a byte of data through the LCD’s DB4~7 pins, in two steps, clocking each with the enable pin.
void LCD4Bit::pushByte(int value){
int val_lower = value & 0x0F;
int val_upper = value >> 4;

//stuff the library user might call---------------------------------
//constructor. num_lines must be 1 or 2, currently.
LCD4Bit::LCD4Bit (int num_lines) {
g_num_lines = num_lines;
if (g_num_lines < 1 || g_num_lines > 4)
g_num_lines = 4;

void LCD4Bit::commandWriteNibble(int nibble) {
digitalWrite(RS, LOW);
if (USING_RW) { digitalWrite(RW, LOW); }

void LCD4Bit::commandWrite(int value) {
digitalWrite(RS, LOW);
if (USING_RW) { digitalWrite(RW, LOW); }
//TODO: perhaps better to add a delay after EVERY command, here. many need a delay, apparently.

//print the given character at the current cursor position. overwrites, doesn’t insert.
void LCD4Bit::print(int value) {
//set the RS and RW pins to show we’re writing data
digitalWrite(RS, HIGH);
if (USING_RW) { digitalWrite(RW, LOW); }

//let pushByte worry about the intricacies of Enable, nibble order.

//print the given string to the LCD at the current cursor position. overwrites, doesn’t insert.
//While I don’t understand why this was named printIn (PRINT IN?) in the original LiquidCrystal library, I’ve preserved it here to maintain the interchangeability of the two libraries.
void LCD4Bit::printIn(char msg) {
uint8_t i; //fancy int. avoids compiler warning when comparing i with strlen()'s uint8_t
for (i=0;i < strlen(msg);i++){

  • }*
    //send the clear screen command to the LCD
    void LCD4Bit::clear(){

  • commandWrite(CMD_CLR);*

  • delay(1);*
    // initiatize lcd after a short pause
    //while there are hard-coded details here of lines, cursor and blink settings, you can override these original settings after calling .init()
    void LCD4Bit::init () {

  • pinMode(Enable,OUTPUT);*

  • pinMode(RS,OUTPUT);*

  • if (USING_RW) { pinMode(RW,OUTPUT); }*

  • pinMode(DB[0],OUTPUT);*

  • pinMode(DB[1],OUTPUT);*

  • pinMode(DB[2],OUTPUT);*

  • pinMode(DB[3],OUTPUT);*

  • delay(50);*

  • //The first 4 nibbles and timings are not in my DEM16217 SYH datasheet, but apparently are HD44780 standard…*

  • commandWriteNibble(0x03);*

  • delay(5);*

  • commandWriteNibble(0x03);*

  • delayMicroseconds(100);*

  • commandWriteNibble(0x03);*

  • delay(5);*

  • // needed by the LCDs controller*

  • //this being 2 sets up 4-bit mode.*

  • commandWriteNibble(0x02);*

  • commandWriteNibble(0x02);*

  • //todo: make configurable by the user of this library.*

  • //NFXX where*

  • //N = num lines (0=1 line or 1=2 lines).*

  • //F= format (number of dots (0=5x7 or 1=5x10)).*

  • //X=don’t care*

  • int num_lines_ptn = g_num_lines - 1 << 3;*

  • int dot_format_ptn = 0x04; //5x7 dots. 0x04 is 5x10*

  • commandWriteNibble(num_lines_ptn | dot_format_ptn);*

  • delayMicroseconds(60);*

  • //The rest of the init is not specific to 4-bit mode.*

  • //NOTE: we’re writing full bytes now, not nibbles.*

  • commandWrite(0x24);//function set, 4 lines and RE=1, N-2Lines*

  • delay(50);*

  • commandWrite(0x09);//extended function set.*

  • delay(50);*

  • commandWrite(0x20);//Re=0*

  • delay(50);*

  • commandWrite(0x0F);//all on*

  • delay(50);*

  • commandWrite(0x01);//clear display*

  • delay(50);*

  • commandWrite(0x06);//*

  • delay(50);*

  • // entry mode set: 06*

  • // increment automatically, display shift, entire shift off*

//non-core stuff --------------------------------------
//move the cursor to the given absolute position. line numbers start at 1.
//if this is not a 2-line LCD4Bit instance, will always position on first line.
void LCD4Bit::cursorTo(int line_num, int x){
//first, put cursor home
if (x>19)
switch (line_num)
case 1:
x+=0x00 ; break;
case 2:
x+= 0x20 ; break;
case 3:
x+= 0x40 ; break; // In fact, line 3 is an extension of the line 1 (beyond the 20 first characters)
case 4:
x+= 0x60 ; break; // Line 4 is an extension of line 2
//scroll whole display to left
void LCD4Bit::leftScroll(int num_chars, int delay_time){

  • for (int i=0; i<num_chars; i++) {*
  • commandWrite(CMD_LEFT);*
  • delay(delay_time);*
  • }*
    and now what I`m trying to do just like example:
    //example use of LCD4Bit library
    #include <LCD4Bit.h>
    *//create object to control an LCD. *
    //number of lines in display=1
    LCD4Bit lcd = LCD4Bit(2);
    void setup() {
  • pinMode(13, OUTPUT); //we’ll use the debug LED to output a heartbeat*
  • lcd.init();*
  • //optionally, now set up our application-specific display settings, overriding whatever the lcd did in lcd.init()*
  • //lcd.commandWrite(0x0F);//cursor on, display on, blink on. (nasty!)*

*void loop() { *

  • digitalWrite(13, HIGH); //light the debug LED*
  • lcd.cursorTo(1, 0);*
  • lcd.printIn(“D”);*
  • lcd.cursorTo(2, 0);*
  • lcd.printIn(“Line 2”);*
  • lcd.cursorTo(3, 0);*
  • lcd.printIn(“Line 3”);*
  • lcd.cursorTo(4, 0);*
  • lcd.printIn(“Line 4”);*
  • digitalWrite(13, LOW); //clear the debug LED*
  • delay(1000);*
    Thank you for ur help. :wink:

And your problem is?

And my problem is....My LCD keeps blank without any character. If..., i plug it out and then plug it on again while arduino is running..., it will give some character which is not what I want.

*can`t write even Hello World yet...sigh

You are using crude code from an old library. Use the LiquidCrystal library from Arduino v0018.

Check this out:

If that doesn't work for you then go to: