Abstract: The present invention provides a system for connecting networks that can automatically avoid address clashes to maintain communication in inter-network communication, which includes a storage unit (5) for storing a table, a comparison unit (2) for comparing an interface address which has been set up in a first interface A1 with a second interface address which is set up in a second interface B1, a network suspension unit for, in response to address clash of the addresses compared by the comparison unit (2), suspending connection between the second network B and an apparatus for connecting networks (1), a readout unit for reading out addresses including a first interface address which is different from the second interface address out of the table stored in the storage unit (5), and an address change unit for changing the interface address which has been set up in the first interface A1 to the first interface address included in the addresses read out by the readout unit.

Abstract: A device for inspecting a printer includes a plurality of interface circuits for a plurality of different kinds of printers. Connectors connect each of the interface circuits to a respective printer. A storage arrangement stores test printing data. A control circuit is connected to select one of the interface circuits and to transmit the test printing data from the storage arrangement to the respective printer for controlling the respective printer to print the test printing data.