An interactive electronic device having a master integrated circuit, an analog audio output device and a bus having a single-conductor digital data link and a single-conductor analog data link and a method for transmitting digital data and an associated analog signal are disclosed. The bus is configured to electrically simultaneously couple the master integrated circuit with any combination of a plurality of removable electronic cartridges arranged in any order in any of a plurality of removable cartridge connectors. The master integrated circuit transmits along the digital data link simultaneously to each of the removable cartridge connectors one identification code of a plurality of identification codes, the identification codes being different from any memory address in any of the removable cartridges. The analog data link simultaneously couples all of the removable cartridge connectors with the analog audio output device and transmits analog signal associated with the one identification code.