The present invention provides a method and apparatus for controlling the operating condition of a peripheral device based on the mode of interconnection of the peripheral device of a host device. The apparatus includes a first connector for connecting the peripheral device, a second connector for connecting the host device and a coupling system operatively interconnecting contacts of the first connector and contacts of the second connector. The coupling system is further configured to provide a supply signal to the peripheral device via the first connector, wherein the supply signal is at least in part indicative of one or more characteristics of the power available to the peripheral device from the host device. The supply signal may provide a means for the peripheral device to control operation thereof in light of the characteristics of the power available.