VooDoo DCR 6000, Planning & Installation Manual

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1. General DCR 6024/6128/6000
1 – 20 Planning and Installation – Rev. 1 / 7. 2001
1.6.3 DATA PROCESSOR DDP 6128
To prevent major modifications in the tapedeck, one of the existing video modes
is for data recording. When in data mode, the tapedeck runs internally in a video
mode (50Hz). So all tapedeck functions like servos, timecode units can be re-
mained unchanged. Only the system software has to be modified for data version.
HPIF Board (HIPPI–Interface)
The optical signal is fed from the input to this board. This board is responsible for
communication with external Hippi devices. A conversion from optical serial signal
to electrical parallel signal is made. A buffer of 128 MBytes allows a flexible han-
dling of incoming data stream. The Hippi header is detected and analyzed. The
header is removed and the data is provided to DPSC board.
DPSC Board
On the DPSC board the internal data controls are processed. Control information
like helical address information (HAI), table of content (TOC), partition information
(PSIT) is generated and inserted in data stream. All required clock generators are
located on this board. The incoming data packet is distributed and segmented into
8 channels.
This board contains also the system control unit.
CORE Board
This board is responsible for the standard digital recorder signal processing steps.
The functions are comparable with the CODC board of the DTV processor. Each
board contains 4 channels, so two identical boards are used in the data processor.
The Reed Solomon error correction encoder adds check bytes to the data bytes.
A rewrite memory stores data and inserts this data again if a rewrite due to error
rate is required.
After channel coding and conversion from parallel to 2bit serial mode, the data is
fed to the tapedeck.
CORE Board
The playback data stream (8channels) is fed to the two boards. Similar functions
compared to the CODC board are implemented:
Channel decoding
Sync detection
Error detection and correction.
For the rewrite function, a error information for rewrite decision is generated.
DPSC Board
The DPSC board extracts and processes all control information that was inserted
in the data stream during record (HAI, TOC). The data signal is combined from the
8 channels.
Record Path
Play Path