Accom ASWR8150, Technical Manual

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Video-Key/Shadow Mode
The Video-Key/Shadow mode is similar to the Video/Key mode, except
that the key signal input to the B channel is processed by the A channel’s
transform controller, so that the video and key are transformed
identically. Also, the key input is used to create a drop shadow. The drop
shadow is routed through the chrominance part of the B circuitry, and
processed by the B channel’s transform controller, which provides
independent shadow transform control. Although the actual signal
paths are the same as in Video/Video mode, from an operational point
of view, the A channel is a 4:2:2:4 path and the B channel is a 4:0:0 path.
The A/B Combiner key output in this mode is a combination of the key
shadow signals processed by the B channel.
DVE Board Indicators
The three green LEDs at the front edge of the DVE board indicate that
the DVE processors are active. They all normally flash at a field rate,
actually appearing continually on. A red LED lights to indicate that the
DVE processor has halted. Press the pushbutton reset switch to reset the
DVE board without affecting the rest of the system.
Figure 4-6 The DVE Board in Video-Key/Shadow Mode
Figure 4-7 DVE Board Front Edge LEDs
8150 Technical Guide Signal Chassis
9100-0212-04 - May 2000
System Overview
4-11