Set-top terminals utilized in broadband broadcast networks are becoming increasingly intelligent (programmable). However, transmitting executable code, data and interactive audio/video materials through a selectively dedicated link requires an extensive, broadband point-to-point broadband network, which is prohibitively expensive to implement for large numbers of customers. The present invention provides for downloading application software and transmitting audio/video information through one channel of a digital broadcast network. The network also provides two-way, low-speed data communications capacity, e.g. for signaling and/or interactive text services. Signaling via data communication with a text server controls downloading of executable code from the digital broadcast channel into a programmable digital set-top terminal. Execution of the downloaded code in turn controls selective capture and presentation of audio and video segments received over one of the digital broadcast channels. Resident operating system and application software in the terminal provides all communication with nodes of the network. The downloaded code forms a non-resident application having a set of predetermined function calls for activating communication functions of the resident software.