#include <LedControl.h>

LedControl lc = LedControl(11, 13, 10, 1);

#define BTN 2

void setup() {
  Serial.begin(9600);

  lc.shutdown(0, false);
  lc.setIntensity(0, 8);
  lc.clearDisplay(0);

  pinMode(BTN, INPUT);
}

void loop() {
  lc.clearDisplay(0);
}