Video system with television receiver and teletext processor capable of switching external RGB signals

摘要

A video system includes a TV receiver, a TTX processor, and a microprocessor control for controlling the functions thereof. The TTX processor includes an RGB switch unit supplied with RGB signals from a shift register in the TTX processor and from an external source of RGB signals. A video coder unit includes RGB switch means for selectively supplying RGB signals from the TTX processor and from the TV receiver and a switch for selectively coupling a timing signal from the TV receiver and the external source. The RGB switch unit in the TTX processor has a TTX address and all switching is controlled by the microprocess.