In order to greatly simplify the electronics of devices utilizing memory cards, a new type of interface specification is presented which is called DPXD for a “Dual Ported eXtended Digital” memory card. The DPXD interface specification comprises an electrical 5 signal set definition based upon a new dual USB concept call Dual Ported USB or DPUSB, a mechanical and electrical definition for a memory card socket, an associated memory card signal and mechanical specification for a memory card, and a mechanical definition for cables compatible with the DPXD socket.