Somerdata R2D3-ASSY-0130, Установка и эксплуатация

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Data Capture Card
Word Alignment
Word alignment is only implemented when the card is set
for
FRAMED data.
The effect of this feature is to place the frame alignment
word into the first Byte of the word that is passed to the
processor.
It is assumed that the little-endian format is used (this is
typical for all Intel PCs).
As the first word in the memory is the frame alignment
word, the first word in any saved file can also be the frame
alignment word.
However, should there be a loss of sync. then the frame
alignment word may appear to move.
This is because the card’s firmware can discard 15 bits
during the alignment process.
Should the loss of bits during re-lock not be acceptable,
then the card should be set for
UNFRAMED data.
Capturing Frame Sync. Errors
It is possible to start a recording as FRAMED data to line
up the frame at the start of the recording, and select
UNFRAMED as soon as the recording has commenced
(e.g. at the first interrupt or data read).
Once UNFRAMED has been selected, the card will capture
all subsequent data errors, slips and omissions.
Note that this will result in the initial recording being in an
obvious frame structure, but after a bit slip the data will
become more difficult to interpret.
Installation and Operation 5-3