The present invention is to provide a KVM device that can perform emulation with any type of device. In this KVM device, firmware for performing a suitable operation for a connected device (KVM) is stored in a memory. The connected device is inspected, and suitable firmware for the device is selected and then installed. The firmware stored in the memory can be rewritten freely. More specifically, the memory is formed by a non-volatile memory so that firmware inputted through an external interface can be stored therein. Thus, the KVM device of the present invention can always cope with the latest type of device.