//El botón de inicio es el verde. Si se quiere parar pero no reiniciar, también el verde. Si se quiere parar Y reiniciar, el rojo.

#include <TM1637TinyDisplay.h>


#define CLK 2  
#define DIO 3  
#define START_STOP_BUTTON 4  
#define RESET_BUTTON 5

 
TM1637TinyDisplay display(CLK, DIO);

 
unsigned long previousMillis = 0;
unsigned long interval = 1000;  
int seconds = 0;
int minutes = 0;
bool running = false;
bool lastStartStopButtonState = HIGH;
bool lastResetButtonState = HIGH;

void setup() {
    
    display.setBrightness(7);

    
    display.showString("0000");

      
    pinMode(START_STOP_BUTTON, INPUT_PULLUP);
    pinMode(RESET_BUTTON, INPUT_PULLUP);

    Serial.begin(9600);
}

void loop() {
   
    bool startStopButtonState = digitalRead(START_STOP_BUTTON);
    if (startStopButtonState == LOW && lastStartStopButtonState == HIGH) {
        
        running = !running;
    }
    lastStartStopButtonState = startStopButtonState;

    
    bool resetButtonState = digitalRead(RESET_BUTTON);
    if (resetButtonState == LOW && lastResetButtonState == HIGH) {
         
        running = false;
        seconds = 0;
        minutes = 0;
        display.showString("0000"); // Display 00:00  
    }
    lastResetButtonState = resetButtonState;

      
    if (running) {
        unsigned long currentMillis = millis();
        if (currentMillis - previousMillis >= interval) {
            previousMillis = currentMillis;
            seconds++;
            if (seconds >= 60) {
                seconds = 0;
                minutes++;
                if (minutes >= 60) {
                    minutes = 0;
                }
            }
            
            char timeString[5];
            sprintf(timeString, "%02d%02d", minutes, seconds);
            display.showString(timeString);
        }
    }
}