A navigation device comprises a data receiver and a Global Positioning System (GPS) navigation device which are interconnected with a multi-pin connector. The data receiver provides an intermediate voltage level through the multi-pin connector, and a microprocessor within the GPS navigation device identifies a type of data transmission system associated with the data receiver. A plurality of intermediate voltage levels may be output wherein each level corresponds to a different type of transmitted data. The data receiver may further comprise a resistor network having a resistance value based on the type of transmitted data.