Snell & Wilcox SD1012, Installation Manual

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Page SD1012 Installation Manual - Issue 6, Rev 1 S&W Production & Post Production 20
CONTROL PORTS AND PROTOCOLS - continued
VTR
Using the Sony VTR (P2) protocol, the Switcher emulates, specifically, a Sony BVH-2000. The
timeline is treated as length of videotape in a virtual VTR controlled by the protocol.
There are two variants of this protocol:
VTR-Ballistics and VTR-No B’stics . The difference is that
on reception of a Preroll (0x20, 0x30) or Cue-Up-With-Data (0x24, 0x31) command, the “Ballistics”
version will jump to one second away from the desired timecode, then slowly roll up to it and stop.
The “No B’stics” version will jump to the desired timecode immediately. The latter mode is quicker,
but may confuse editors that do not expect one-inch tape decks to be so athletic!
To enable this function to operate,
F1R Time Touch must be On in the main TIMELINE menu.
Follow Real VTR
This protocol allows the switcher’s timeline to follow the tape motion of a real VTR, or indeed any
device supporting Sony VTR (P2) protocol. This allows, for example, a switcher timeline to be built
that has different colour-correction settings for each scene on a tape.
To enable this function to operate,
F1R Time Touch must be On in the main TIMELINE menu.
There are two ways of using this protocol.
1 The switcher emulates an editor (it becomes a controlling device) and locks the switcher’s
timeline to timecode it requests from the VTR.
In this case, simply plug a normal pin-to-pin 9-pin cable between the designated port on the
switcher and the remote port of the VTR.
2 Alternatively in a system that has an editor (or other controlling device) connected to the
VTR, a special “sniffer” arrangement is inserted into the control cable between the editor
and the VTR. This allows the switcher to monitor the timecode replies transmitted from the
VTR to the editor, while preventing the switcher’s timecode requests clashing with those
from the editor. Note: this method relies on the editor transmitting timecode requests to the
VTR. Most editors do this at least once a field; however some designs only transmit such
requests once every few fields. This interface will not work as well with such editors.
The special connector arrangement required is as follows:
To Editor (or VTR) To VTR (or Editor)
To Switcher’s
“Follow Real VTR” port
9-way female D-Type 9-way male D-type 9-way female D-type
Function Pin Pin Function Pin Function
Frame Ground 1 ------------- 1 Frame Ground ------------- 1 Frame Ground
Rx A 2 ------------- 2 Tx A ------------- 2 Rx A
Tx B 3 ------------- 3 Rx B -- CUT -- 3 Tx B
Tx Common 4 ------------- 4 Rx Common -- CUT -- 4 Tx Common
[Unused] 5 5 [Unused] 5 [Unused]
Rx Common 6 ------------- 6 Tx Common ------------- 6 Rx Common
Rx B 7 ------------- 7 Tx B ------------- 7 Rx B
Tx A 8 ------------- 8 Rx A -- CUT -- 8 Tx A
Frame Ground 9 ------------- 9 Frame Ground ------------- 9 Frame Ground
The left-hand two connectors form a transparent loop-through between the editor and the VTR, and
can be connected either way round. The right-hand connector should be plugged into a cable
leading to the switcher.