local function leave()
  local pin = "1234"
  gpu.fill(1,1,20,5," ")
  gpu.setForeground(0xFF0000)
  gpu.set(2,2,"Enter PIN:")
  gpu.set(2,4,"_ _ _ _")
  local num = 1
  local col = 2
  local inpin
  while ture do
    local ka,ch,co,pn = event.pull(20,"key_down")
    if ka == nil then init() end
    gpu.set(col,3,"*")
    inpin = inpin .. ch
    num = num + 1
    col = col + 2
    if num == 5 then break end
  end
  if inpin == pin then
    gpu.setResolution(gpu.maxResolution())
    gpu.fill(1,1,w,h," ")
    interrupt = true
  else
    init()
  end
end
event.listen("interrupted",leave)