A/B Roll Editing; Turning A Downstream Key On And Off - Sony DFS-700 Service Manual

Control Using GPI Signals

A/B Roll Editing

Signal flow
The flow of signals in A/B roll editing is as follows.
For more information about connections, "see Connections for an A/B Roll
Editing System" (page 6-5).
Player VCR A
DFS-700/700P
VIDEO
Foreground bus
video INPUT
Background bus
VIDEO
video
Player VCR B INPUT
Control signal
Control signal
Editing control unit
Note
To improve editing accuracy, supply a reference sync signal to the editing control unit and
the VCRs from the BLACK BURST OUT connectors on the DFS-700/700P.
Signal flow in A/B roll editing
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Chapter 5 Control From Editing Control Units
Recorder VCR
PGM OUT
GPI signals
Control signal
Timing of the GPI signal
The timing of the GPI signal from the editing control unit is as follows.
VCRs start IN point Effect start point
Player A
Player B
Recorder
GPI signal
3 frames
PGM OUT
signal Background bus image
Preroll
A-roll period
Timing of GPI signal in A/B roll editing

Turning a Downstream Key On and Off

If in page 1 of the setup menu you have set F3(PORTS) to "PVE-500" or
"GPI" then you can turn a downstream key on and off using a GPI signal
input to the T2 connector on the DFS-700/700P.
As shown below, the downstream key is turned alternately on and off at
the falling edge of the GPI signal.
GPI signal
3 frames
DSK ON
Turning a downstream key on and off — GPI signal timing
OUT point
VCRs stop
Foreground bus
image
Execution of Postroll
effect (transition)
B-roll period
3 frames
DSK OFF
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Chapter 5 Control From Editing Control Units