def blocked=(val)
      if ! [ true, false ].include?(val)
        raise ArgumentError, "value must be a boolean"
      end
      @o_dev[I_DEVICE]['Blocked'] = val
    end
def blocked=(val)
      if ! [ true, false ].include?(val)
        raise ArgumentError, "value must be a boolean"
      end
      @o_dev[I_DEVICE]['Blocked'] = val
    end
If set to true any incoming connections from the
 device will be immediately rejected. Any device
 drivers will also be removed and no new ones will
 be probed as long as the device is blocked
 @param val [Boolean]
 @return [void]