A card type electronic device system has an adapter including a self-identification function compliant with a preselected recognition procedure for identifying the adapter. A card type electronic device is provided for selective connection to one of a first card slot of a host device without the adapter and to a second card slot of the host device via the adapter that has a maximum supply current standard value greater than that of the first card slot. The card type electronic device includes a recognition function via which the adapter is recognized in accordance with the preselected recognition procedure. A control function of the card type electronic device selects predetermined operation conditions which match the maximum supply current standard value of the first card slot when the recognition function recognizes that the card type electronic device is connected to the first card slot, and selects predetermined operation conditions which match the maximum supply current standard value of the second card slot when the recognition function recognizes that the card type electronic device is connected to the second card slot.