   {
     String sbuf(buf);
   
+    if(sbuf[0] == 'z' && index == 2)
+    {
+      if(isTimerEnabled())
+      {
+        disableTimer();
+      }
+      else
+      {
+        enableTimer();
+      }
+      
+      Serial.println(" OK ");
+    }
+  
     if(sbuf[0] == 'b' && index == 5)
     {
       String s("");

  sei(); 
}

#define DEVICES 4
#define DEVICES_ARRAY_SIZES 4
#define ROWS 8

} 
void runGrid() 
{
  
  for(uint8_t x = 0; x < WIDTH; ++x) {
    for(uint8_t y = 0; y < HEIGHT; ++y) {

