24 = Hardware Interface
Most broadcast automation systems, and some remote control panels employ the VDCP
protocol. A detailed list of supported VDCP commands will be found in Appendix B.
Many controllers used for transport, instant replay, and edit control employ P2 or Odetics
protocol. The Image Server P2 protocol emulates BVW-series tape machines. Many Pro-AV
systems employ AMX and Crestron protocol.
Gigabit Ethernet Ports
Two Gigabit Ethernet ports are provided on the Image Server. The NET 1 port is intended for
network transfer of program content between video servers. The server supports MXF file
transfer (MPEG-2, Op 1a and 1b), which allows content interchange between products from
different manufacturers, as well as file import in various formats from desktop editors. The
NET 2 port is reserved for data transfer between two Image Servers, when configured for
redundant operation.
GPI Control
The Image Server provides six GPI inputs for control of machine functions, which appear on
the 25-pin GPI connector. This “General Purpose Interface” can be connected to switch
contacts or an open-collector transistor output. GPI inputs are programmable, and can provide
machine control such as PLAY, STOP, or RECORD through simple external switches.
The Image Server also provides six GPI status outputs which may be used to confirm that a
command has been received, or for other purposes. These functions of these open-collector
outputs are programmable, and may be used to operate an LED, or they can be connected to a
suitable logic input. The pin-out for the GPI connector will be found in Connector
Specifications.
Genlock Sync Reference
A BNC connector is provided on the rear panel to receive a genlock signal. During normal
operation, the Image Server should be referenced to an external genlock reference in the form
of CVBS Black. As with all video systems, this server and equipment connected to it must be
referenced to a common genlock source. The GENLOCK input provides a fixed 75-ohm
termination.
An internal crystal reference is also provided so that the server can be used as a stand-alone
player, and also for convenience in performing tests in the laboratory. Use particular care
when operating the server with an internal reference, as synchronization with other equipment
is not possible. Additionally, recording is not allowed when using the internal crystal.
Genlock Signal Quality
A genlock signal connected to the Image Server must conform to the RS-170A standard. PLL
circuits used within the server remove residual jitter from the genlock signal. This may
preclude the use of low-cost VTRs that introduce time instability (wow) into their output,
making them inaccurate as a genlock input source.