GRASS VALLEY Profile XP PVS1000, Service Manual

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Appendix B Theory of operation
164 Profile XP Service Manual 23 July 2004
Serial Digital Interface (SDI) boards
The SDI boards used in the Profile XP media platform provide either two input and
two output ports, or four output ports.
The SDI inputs receive serial component video conforming to SMPTE 259M. The
input decoder synchronizes the incoming video to the Profile XP internal video
timing and converts the serial stream into 10-bit component 4:2:2 video that is sent to
the video/audio crosspoint fabric.
The SDI outputs accept 10-bit component 4:2:2 video from the video/audio crosspoint
fabric. Circuitry on the board performs blanking, HANC data insertion, VITC data
insertion, and variable delay. The resulting video output is a SMPTE 259M
compatible bit stream.
High Definition Serial Digital Interface Board
The HD SDI board, through four BNC connectors, provides one SMPTE292M serial
digital video input, one SMPTE292M serial digital video output, a standard SDI
(SMPTE 259M) output, and a composite analog NTSC or PAL monitor output.
Functionality on the board includes embedded audio insertion or extraction, time code
insertion and extraction (as horizontal ancillary data), input and output timing, and
closed caption insertion to and extraction from vertical interval ancillary data.
The HD-SDI board can function as both input and output if AES/EBU audio is in use,
but when embedded audio is used, the board functions either as input or output but not
both. The output on the standard SDI port and monitor port is down-converted from
the high definition output signal. The composite analog monitor output includes Text
Overlay and Timecode burn-in.
Serial Data Transfer Interface (SDTI) Board (optional)
This board provides two SDTI channels, each with an input and an output BNC
connector. From the compressed video at the input, this board extracts video and
audio data and sends it to the media storage subsystem. At its output, this board
provides formatted video and audio data retrieved from the media storage subsystem.
Video network adapter (optional)
The Video Network Adapter is a 1Gb/s Fibre Channel board or 100BaseT Ethernet
board for video network connections. Both provide faster than real-time transfers of
video data.
The purpose of the video network is to provide high-speed transfer of media files
between different media storage systems such as other Profile XP systems or a large
computer file server. The video networking I/O also provides the resource to move
data to and from buffers in the real time subsystem's PCI memory space. The video
networking I/O is controlled by the RTP via the PCI bus.