#include <Keypad.h>
#include <Adafruit_SSD1306.h>

const int OLED_SDA = 21;
const int OLED_SCL = 22;
#define LARGURA_OLED 128
#define ALTURA_OLED 64
#define RESET_OLED -1

Adafruit_SSD1306 display(LARGURA_OLED, ALTURA_OLED, &Wire, RESET_OLED);

const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char keys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};


uint8_t colPins[COLS] = { 2, 4, 5, 18 }; // Pins connected to C1, C2, C3, C4
uint8_t rowPins[ROWS] = { 19, 16, 15, 23 }; // Pins connected to R1, R2, R3, R4
char message[255];

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

void setup() {
  Serial.begin(11520);
  Serial.println("Keypad-OLED demo");
  Wire.begin(OLED_SDA,OLED_SCL);
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C))
    Serial.println("Falha ao abrir display");
  else
    display.clearDisplay();
}

void drawSimpleText(char* message)
{
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextWrap(true);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);
  display.println(message);
  display.display();
}

void loop()
{
  char key = keypad.getKey();

  if (key != NO_KEY)
  {
    Serial.println(key);
    sprintf(message,"Tecla %d", key);
    drawSimpleText(message);
  }
  delay(10);
}