Sony 702P 1-64, Control Using GPI Signals, A/B Roll Editing, Turning a Downstream Key On and Off

1-64
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	Recorder VCR
Foreground bus	VIDEO DFS-700/700P
video	INPUT
	PGM OUT
Background bus	VIDEO
Player VCR B video	INPUT
	GPI signals
Control signal
	Control signal
Control signal
	Editing control unit
Chapter	Note
	To improve editing accuracy, supply a reference sync signal to the editing control unit and
5	the VCRs from the BLACK BURST OUT connectors on the DFS-700/700P.
Control Control	Signal flow in A/B roll editing
From Units
Editing

DFS-700/700P 5-12 Chapter 5 Control From Editing Control Units

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			OUT point VCRs stop
Player A
Player B
Recorder
GPI signal			3 frames
PGM OUT						Foreground bus
signal		Background bus image				image
Preroll				Execution of		Postroll
				effect (transition)
			A-roll period		B-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		3 frames
DSK ON		DSK OFF

Turning a downstream key on and off — GPI signal timing

Chapter 5 Control From Editing Control Units 5-13

Chapter 5 Control From Editing Control Units