Abstract: A communication network for providing communication between multiple sources and multiple destinations includes a source selector (34; 70, 72; 90, 98) having a plurality of input terminals (22) for connection to respective sources (30), at least one output terminal (20; 100), and crosspoint elements (38; 80, 82; 92, 98) for connecting any selected set of the input terminals to the output terminal. A destination selector (18; 100) has at least one input terminal (20) connected to the output terminal of the source selector, a plurality of output terminals (24) for connection to respective destinations (30), and crosspoint elements (28; 102) for connecting the input terminal of the destination selector to any selected set of the output terminals of the destination selector.

Abstract: A transition interrupt for a video switcher which occurs at any point during or just prior to a transition between a program bus source and a preset bus source replaces the source on the preset bus with a new source. The program bus executes a cut or fade to black of the current source, and then the new source from the preset bus is switched to the program bus so that the new source is now on the program bus at black. The program bus is held at black, if necessary, until any necessary initial activation sequence is completed, such as preroll for a tape or cassette recorder, and then brought up from black to complete the new transition due to the transition interrupt.

Abstract: A transition status display for a video switcher inserts a single, readable synopsis of a next transition event into a video output signal from the video switcher for display on a monitor. The synopsis is in the form of a window having a line segment representing a time line between a prior transition event and the next transition event, the type of the next transition event being indicated graphically. Various tic marks represent significant events in time from an initial tic mark representing the time of the prior transition through a final tic mark representing completion of the next transition. Appropriate alpha-numeric characters are provided with the line segment to label the significant events, to identify the current and next video sources, and to provide time information, the time information being constantly updated together with an analog marker which moves along the line segment as time progresses toward the next transition.

Abstract: Television camera apparatus for generating auxiliary signals such as a VITC signal, an alphanumeric character generating signal, and a window signal for use in gating video related signals to camera adjustment circuitry. The apparatus includes a memory for storing data words representative of auxiliary signals to be generated, a microprocessor for accessing the data words from the memory, and a parallel-in/serial-out (PISO) shift register for receiving the accessed data words in parallel and for shifting them out bit serial so as to thereby generate the auxiliary signal. A first-in/first-out (FIFO) register interfaces the PISO shift register to the microprocessor and memory. The microprocessor uses an internal "refresh" register, normally used to refresh dynamic memories, to access data words for loading into the FIFO. The same circuitry is used for generating plural auxiliary signals.