A control unit is set up to operate a target device by receiving a first input for selecting from a plurality of protocols stored in the control unit a protocol that is appropriate for communicating with the target device. The control unit is then caused to transmit to the target device, using the selected protocol, a request for configuration information. In response to the receipt of the request, the target device returns to the control unit a function indicator and the control unit selects from a plurality of commands appropriate for the target device stored in the control unit a command corresponding to the function indicator. The selected command is mapped to a function key of the control unit such that activation of the function key results in communication of the selected command using the selected protocol to the target device to thereby control a function supported by the target device that is represented by the function indicator. The function indicator may alternatively be a code that indicates to the control unit that data following the code is a definition of a new infrared code and a corresponding key annotation.