-Arduino / nodemcu
- Lcd 16x2 i2c atau yang lainnyq
- push button
- Jumper
Skematik :
Program:
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F,16,2); // set the LCD address to 0x27 for a 16 chars and 2 line display
// Variabel pin push button
const int Up_buttonPin = 2;
const int Down_buttonPin = 3;
// Variables will change
int buttonPushCounter = 0; // counter jika tidak ditekan
int up_buttonState = 0; // current jika tidak ditekan
int up_lastButtonState = 0; // previous state dari push button
int down_buttonState = 0; // current state of the up button
int down_lastButtonState = 0; // previous state of the up button
bool bPress = false;
void setup()
{
Serial.begin(9600);
pinMode( Up_buttonPin , INPUT_PULLUP);
pinMode( Down_buttonPin , INPUT_PULLUP);
lcd.init(); // initialize the lcd
// Print a message to the LCD.
lcd.backlight();
lcd.setCursor(0,0);
lcd.print("silahkan pilih:");
lcd.setCursor(2,1);
lcd.print(buttonPushCounter);
}
void loop()
{
checkUp();
checkDown();
if( bPress){
bPress = false;
lcd.setCursor(2,1);
lcd.print(" ");
lcd.setCursor(2,1);
lcd.print(buttonPushCounter);
}
}
void checkUp()
{
up_buttonState = digitalRead(Up_buttonPin);
// compare the buttonState to its previous state
if (up_buttonState != up_lastButtonState) {
// if the state has changed, increment the counter
if (up_buttonState == LOW) {
bPress = true;
// if the current state is HIGH then the button went from off to on:
buttonPushCounter++;
Serial.println("on");
Serial.print("number of button pushes: ");
Serial.println(buttonPushCounter);
} else {
// if the current state is LOW then the button went from on to off:
Serial.println("off");
}
// Delay a little bit to avoid bouncing
delay(50);
}
// save the current state as the last state, for next time through the loop
up_lastButtonState = up_buttonState;
}
void checkDown()
{
down_buttonState = digitalRead(Down_buttonPin);
// compare the buttonState to its previous state
if (down_buttonState != down_lastButtonState) {
// if the state has changed, increment the counter
if (down_buttonState == LOW) {
bPress = true;
// if the current state is HIGH then the button went from off to on:
buttonPushCounter--;
Serial.println("on");
Serial.print("number of button pushes: ");
Serial.println(buttonPushCounter);
} else {
// if the current state is LOW then the button went from on to off:
Serial.println("off");
}
// Delay a little bit to avoid bouncing
delay(50);
}
// save the current state as the last state, for next time through the loop
down_lastButtonState = down_buttonState;
}