Abstract: A system based on codes permits the management of static and dynamic object streams including virtual static objects, object I/O, typed object I/O, and object multiplexing and demultiplexing. System information consists of codes and non-code information which exists within objects which may be typed, and may exist within static or dynamic streams.

Abstract: Apparatus for transmitting analog voice and data communications on a phone line utilizing a telephone, a data terminal and a modem, the modem being connected to the data terminal. The apparatus comprises a mode switch for connection to the phone line, to the modem and to the telephone, the mode switch having at least first and second positions. When in the first position, the phone line is connected to the modem and when in the second position the phone line is connected to the telephone. A controller is connected to the mode switch for placing the mode switch in the first position or in the second position. A data transition tone generator is connected to the controller and to the phone line, and an actuator is provided for actuating the tone generator to produce a tone signal on the phone line at substantially the time that the contoller changes the position of the mode switch.