*** download circuit diagram and complete keypad (4*3) interfacing code.***
1. circuit diagram ......
2.**** for more information watch video ****
3. *******complete code ******* by sani edu technical*****
// Including LCD library
#include<LiquidCrystal.h>
// Setting (RS,E,D4,D5,D6,D7) for particular pin number
LiquidCrystal lcd(6, 5, 4, 3, 2, 1);
int c1 = 11, c2 = 12, c3 = 13;
int r1 = 10, r2 = 9, r3 = 8, r4 = 7;
int del = 600;
void setup() {
lcd.begin(16, 2);
lcd.setCursor(0, 0);
lcd.print("Hello !");
delay(1000);
lcd.clear();
/* use input pull-up *//
*/
pinMode(c1, INPUT_PULLUP);
pinMode(c2, INPUT_PULLUP);
pinMode(c3, INPUT_PULLUP);
// Set r1,r2,r3,r4 pins to OUTPUT mode
pinMode(r1, OUTPUT);
pinMode(r2, OUTPUT);
pinMode(r3, OUTPUT);
pinMode(r4, OUTPUT);
}
void loop() {
row1();
row2();
row3();
row4();
}
void row1() {
digitalWrite(r1, LOW);
digitalWrite(r2, HIGH);
digitalWrite(r3, HIGH);
digitalWrite(r4, HIGH);
if (digitalRead(c1) == LOW) { //print 1,2,3
lcd.print("1"); delay(del);
}
else if (digitalRead(c2) == LOW) {
lcd.print("2"); delay(del);
}
else if (digitalRead(c3) == LOW) {
lcd.print("3"); delay(del);
}
}
void row2() {
digitalWrite(r1, HIGH);
digitalWrite(r2, LOW);
digitalWrite(r3, HIGH);
digitalWrite(r4, HIGH);
if (digitalRead(c1) == LOW) { //print 4,5.6
lcd.print("4"); delay(del);
}
else if (digitalRead(c2) == LOW) {
lcd.print("5"); delay(del);
}
else if (digitalRead(c3) == LOW) {
lcd.print("6"); delay(del);
}
}
void row3() {
digitalWrite(r1, HIGH);
digitalWrite(r2, HIGH);
digitalWrite(r3, LOW);
digitalWrite(r4, HIGH);
if (digitalRead(c1) == LOW) { ///print 7,8,9
lcd.print("7"); delay(del);
}
else if (digitalRead(c2) == LOW) {
lcd.print("8"); delay(del);
}
else if (digitalRead(c3) == LOW) {
lcd.print("9"); delay(del);
}
}
void row4() {
digitalWrite(r1, HIGH);
digitalWrite(r2, HIGH);
digitalWrite(r3, HIGH);
digitalWrite(r4, LOW);
if (digitalRead(c1) == LOW) { ///print *,0,#
lcd.print("*"); delay(del);
}
else if (digitalRead(c2) == LOW) {
lcd.print("0"); delay(del);
}
else if (digitalRead(c3) == LOW) {
lcd.print("#"); delay(del);
}
}
