#include <Arduino.h>
#define COM_PIN 2
const uint8_t CONTROL_PINS[] = {3, 4, 5, 6};
const int LED_PIN = A0;
char readButton(int channel)
{
for (int i = 0; i < 4; i++)
{
digitalWrite(CONTROL_PINS[i], (channel >> i) & 1);
}
delay(10);
int buttonState = digitalRead(COM_PIN);
char buttonChar = 'A' + channel;
return buttonState == HIGH ? buttonChar : '\0';
}
void setup()
{
Serial.begin(9600);
pinMode(COM_PIN, INPUT);
for (int i = 0; i < 4; ++i)
{
pinMode(CONTROL_PINS[i], OUTPUT);
}
pinMode(LED_PIN, OUTPUT);
}
void loop()
{
for (int i = 0; i < 16; ++i)
{
char buttonPressed = readButton(i);
if (buttonPressed != '\0')
{
Serial.println(buttonPressed);
digitalWrite(LED_PIN, HIGH); // Turn on LED when a button is pressed
delay(100);
}
digitalWrite(LED_PIN, LOW); // Turn off LED after delay
}
}