def show
      closed!
      if @debug
        ary = @leds.map { |value| Rainbow(@debug).color(*to_rgb(value)) }
        $stdout.print "\r#{ary.join}"
      end
      self
    end
def show
      closed!
      if @debug
        ary = @leds.map { |value| Rainbow(@debug).color(*to_rgb(value)) }
        $stdout.print "\r#{ary.join}"
      end
      self
    end
Update the display with the data from the LED buffer. This is a noop method
 for the fake LEDs.