hej,
here is a codeexample for an lcd-display with 4 datapins, if you want i have also a nice pdf with some pictures, schematics and so on ....
tomek
/* LCD display with 4 DataPins
* --------
*
* This is a example in how to use an LCD screen
* configured with data transfers over 2 x 4 bits. The example
* based on the "LCD Hola example" by DojoDave.
*
* There are the following pins to be considered:
*
* - DI, RW, DB0..DB3, Enable (7 in total)
*
* the pinout for LCD displays is standard and there is plenty
* of documentation to be found on the internet.
*
* (cleft) 2006 Tomek for K3 and fh-potsdam
*
*/
int led = 13;
int DI = 12;
int RW = 11;
int DB[] = { 7, 8, 9, 10};
int Enable = 6;
int count = 0;
void LcdCommandWrite(int value) {
int i = 0;
int value1 = 0;
value1 = value;
value1 >>= 4; //send the first 4 databits (from 8) + RW and DI
for (i=DB[0]; i <= DI; i++) {
digitalWrite(i,value1 & 01);
value1 >>= 1;
}
digitalWrite(Enable,LOW); // send a pulse to enable
delayMicroseconds(1);
digitalWrite(Enable,HIGH);
delayMicroseconds(1);
digitalWrite(Enable,LOW);
delayMicroseconds(1); // pause 1 ms according to datasheet
delay(1);
for (i=DB[0]; i <= DB[3]; i++) { // secound part of the secound 4 bits (from 8)
digitalWrite(i,value & 01);
value >>= 1;
}
value >>= 4; // send the RW and DI of the secound 4 bits(from 8)
for (i=RW; i <= DI; i++) {
digitalWrite(i,value & 01);
value >>= 1;
}
digitalWrite(Enable,LOW); // send a pulse to enable
delayMicroseconds(1);
digitalWrite(Enable,HIGH);
delayMicroseconds(1);
digitalWrite(Enable,LOW);
delayMicroseconds(1); // pause 1 ms according to datasheet
}
void LcdDataWrite(int value) {
int i = 0;
int value1 = 0;
digitalWrite(DI, HIGH);
digitalWrite(RW, LOW);
value1 =value;
value1 >>= 4; //send the first 4 databits (from 8)
for (i=DB[0]; i <= DB[3]; i++) {
digitalWrite(i,value1 & 01);
value1 >>= 1;
}
digitalWrite(Enable,LOW); // send a pulse to enable
delayMicroseconds(1);
digitalWrite(Enable,HIGH);
delayMicroseconds(1);
digitalWrite(Enable,LOW);
delayMicroseconds(1); // pause 1 ms according to datasheet
delay(1);
digitalWrite(DI, HIGH);
digitalWrite(RW, LOW);
for (i=DB[0]; i <= DB[3]; i++) {
digitalWrite(i,value & 01);
value >>= 1;
}
digitalWrite(Enable,LOW); // send a pulse to enable
delayMicroseconds(1);
digitalWrite(Enable,HIGH);
delayMicroseconds(1);
digitalWrite(Enable,LOW);
delayMicroseconds(1); // pause 1 ms according to datasheet
}
// this funktion help us to write number over 9, easyely in the lcd display
void LcdNumberWrite(int nr) {
int n1 = 0;
int n2 = 0;
n1 = n2 = nr;
n1 = n1 / 100;
LcdCommandWrite(560 + n1); //512 used to wirte data (see commands for character modul)
n2 = (n2 - n1 * 100) / 10;
LcdCommandWrite(560 + n2); //512 used to wirte data (see commands for character modul)
nr = nr - n1 *100 - n2 * 10;
LcdCommandWrite(560 + nr); //512 used to wirte data (see commands for character modul)
}
void setup (void) {
int i = 0;
for (i=Enable; i <= DI; i++) {
pinMode(i,OUTPUT);
}
delay(100);
// initiatize lcd after a short pause
// needed by the LCDs controller
////////////////////////////// 4 pin initialization
LcdCommandWrite(0x03); // function set:
// 4 pin initialization
delay(64);
LcdCommandWrite(0x03); // function set:
// 4 pin initialization
delay(50);
LcdCommandWrite(0x03); // function set:
// 4 pin initialization
delay(50);
LcdCommandWrite(0x02); // function set:
// 4 pin initialization
delay(50);
LcdCommandWrite(0x2C); // function set:
// 4-bit interface, 1 display lines, 5x7 font
///////////////////////////////////////////////////// end of 4 pin initialization
delay(20);
LcdCommandWrite(0x06); // entry mode set:
// increment automatically, no display shift
delay(20);
LcdCommandWrite(0x0E); // display control:
// turn display on, cursor on, no blinking
delay(20);
LcdCommandWrite(0x01); // clear display, set cursor position to zero
delay(100);
LcdCommandWrite(0x80); // display control:
delay(20);
//////// unter this line are the special stuff you don't need for a initialitzation
LcdCommandWrite(0x0F); // cursor blink
delay(10);
}
void loop (void) {
//>>>>>>>>>>>>>>possible commands for the Lcd Display>>>>>>><< able to use for LcdDisplays with 4 or with 8 DataPins
//LcdCommandWrite(0x01); // clear display, set the cursor to home position
//LcdCommandWrite(0x02); // set cursor position to zero
//LcdCommandWrite(0x0A); // set the display off
//LcdCommandWrite(0x0E); // set the display on and with out cursor blink
//LcdCommandWrite(0x0F); // set the display on and with cursor blink
//LcdCommandWrite(0x0F); // cursor blink
//LcdCommandWrite(0x0E); // cursor not blink
//LcdCommandWrite(0x18); // shift display and cursor to the left
//LcdCommandWrite(0x1c); // shift display and cursor to the right
//LcdCommandWrite(0x14); // shift cursor to the right
//LcdCommandWrite(0x10); // shift cursor to the left
//>>>>>>>>>>>>>>>>>>>>>> example <<<<<<<<<
LcdCommandWrite(0x02); // set cursor position to zero
delay(10);
// Write the message
//like this
LcdDataWrite('L');
LcdDataWrite('c');
LcdDataWrite('d');
//or like this
for ( count = 0; count<=7; count++) {
int wrote [] = { 'D', 'i', 's', 'p', 'l', 'a', 'y', ' ', 'w', 'i', 't', 'h',' ' };
LcdDataWrite(wrote[count]);
}
// and Number over 9 easyely like this
LcdNumberWrite(4);
LcdDataWrite('P');
LcdDataWrite('i');
LcdDataWrite('n');
LcdDataWrite('s');
delay(3000);
}
