kamaji_v3_test.cpp

#include <LiquidCrystal.h>
#include <Wire.h>

const int speakerPin = 9;
const int lampPin = 8;
const int controlButtons = 3;
const int controlButtonPins[] = { 12, 13, 11 };
const int playerButtons = 6;
const int playerButtonPins[] = { 5, 4, 3, 2, 1, 0 };

LiquidCrystal lcd(7, 6, A0, A1, A2, A3);

void setup() {
  Wire.begin();
  pinMode(speakerPin, OUTPUT);
  lcd.begin(20, 4);
  lcd.write("Hello world!");

  pinMode(lampPin, OUTPUT);

  for (int i = 0; i < playerButtons; i++) {
    pinMode(playerButtonPins[i], INPUT_PULLUP);
  }
  for (int i = 0; i < controlButtons; i++) {
    pinMode(controlButtonPins[i], INPUT_PULLUP);
  }
}

void flash() {
  tone(speakerPin, 2000);
  digitalWrite(lampPin, HIGH);
  ExpanderWrite(0x20, 0xff);
  
  delay(1000);
  
  noTone(speakerPin);
  digitalWrite(lampPin, LOW);
  ExpanderWrite(0x20, 0x00);
}

void loop() {
  while (true) {
    for (int i = 0; i < playerButtons; i++) {
      if (digitalRead(playerButtonPins[i]) == LOW) {
        lcd.setCursor(0, 1);
        lcd.write("PLR ");
        lcd.write('0' + i);
        flash();
      }
    }

    for (int i = 0; i < controlButtons; i++) {
      if (digitalRead(controlButtonPins[i]) == LOW) {
        lcd.setCursor(0, 1);
        lcd.write("CTL ");
        lcd.write('0' + i);
        flash();
      }
    }
  }
}

void ExpanderWrite(byte address, byte value) {
  Wire.beginTransmission(address);
  Wire.write(value);
  Wire.endTransmission();
}