Somerdata R2D3-ASSY-0130, Установка и эксплуатация

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R
2
D
3
Data Capture Card
Installation and Operation 5-4
DAB ETI-NI/ETI-NA Frame recognition
Card versions: R2D3-ASSY-0130 (before September 2003)
R2D3-ASSY-0131 (from September 2003)
R2D3-ASSY-0431
For ETI-NI signals, incoming data will only be transferred to
the buffer once three consecutive ETI-NI (G.703) frame sync
words have been received (073AB6
H
).
For ETI-NA signals, incoming data will only be transferred to
the buffer once three consecutive ITU (G.704) frame sync
words have been received (S0011011
2
), where S is a
signalling bit).
The stream will only be deemed to be locked if 3 frames have
been received with 2 valid frame sync words as above,
alternated with the alternate frame sync word.
Once locked, the stream will stay locked unless 3 consecutive
frame sync words fail to be found in the expected bit positions.
In the event of this occurring, the locking procedure as
described above will recommence.
If the stream has already commenced recording, the received
data will be faithfully passed through to be recorded.
The only exception to this is if on re-locking, the frame is no
longer in the same relative word position as under the
previous lock condition.
In this event up to 15 bits will be lost while word-alignment is
implemented.