PURPOSE: To prevent the malfunction caused when a pack is removed in an ON-LINE mode by attaining automatically an OFF-LINE state after a printing action in case the pack is removed in a printing mode and also in an ON-LINE state.

CONSTITUTION: The control system of a recording device 1 has such constitution where the OFF-LINE state is set automatically in case no function in a pack 7 is used, i.e., the print data supplied from the host side is not converted into a dot matrix and also when the pack 7 is removed in a non-print made and in an ON-LINE state. At the same time, an OFF-LINE state is set automatically after a printing action in case the pack 7 is removed in a print mode and in an ON-LINE state. In such a case, it is desirable to set an ON-LINE state automatically in case the pack 7 is attached again after an OFF-LINE state is set.