A system integrating a bar code printer and a bar code reader into a single functional unit having a single interface port which serves both the printer and the reader and communicates with a host computer. The interface port can include a parser to receive commands from the host computer and parse the received commands into printer and reader commands. The printer and the reader can communicate directly with each other without requiring the intervention of the host computer. The interface can include a wireless transceiver to permit remote operation of the unit. The unit can also be a stand alone system that does not require the host computer. In the standalone embodiment, an internal controller generates commands to control operation of the printer and receiver. The standalone instrument can also include an interface to communicate with an optional host computer.