local function redraw()
local bl = {
  {
    "Ÿ",
    "990",
    "009",
  },
  {
    "• •",
    "900",
    "099",
  },
  {
    "‚ƒ",
    "000",
    "999",
  },
}
if self.value then
    bl[2][1] = "•x•"
end
for t=1,3 do
term.setCursorPos(1,t)
term.blit(unpack(bl[t]))
end
end
while true do
os.pullEvent()
redraw()
end