#include <mechButton.h>
#define LED 3     

mechButton  redBtn(2);  
timeObj     LEDTimer(5000); 

void setup() {
  pinMode(LED,OUTPUT);
  digitalWrite(LED,LOW);
  redBtn.setCallback(btnClicked);
}

void btnClicked(void) {

  if (!redBtn.trueFalse()) {
    digitalWrite(LED,HIGH);     
    LEDTimer.start();
  }
}

void loop() {

  idle(); 
  if (LEDTimer.ding()) {
    digitalWrite(LED,LOW);
    LEDTimer.reset();
  }
}