Thread: Raymarine C120
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Bruce in alaska Bruce in alaska is offline
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First recorded activity by BoatBanter: Dec 2007
Posts: 153
Default Raymarine C120

In article ,
Larry wrote:

"WBH" wrote in
news:fr1hee $bjk$1@ lust.ihug.co.nz:

The only way to resolve
this is to use a device which can 'convert' the baud-rate from 38400 to
4800 bps


Wouldn't this soon be overrun with data pouring in at 38400 and dripping
out at 4800? If there's a lot of AIS targets, is 4800 fast enough to keep
the converter memory from being overrun??


Larry, your assuming that the data is a continuous stream from the 38K
data source. This is a BIG Assumption, and I would bet that the data is
burst or packetized, and the actual 38K thru-put is actually less than
that of the 4800 NEMA thru-put. If you were right and the 38K data was
Streaming, then I suspect that only a fraction of that data is required
represent the AIS information, when converted to the NEMA 4800 required
Sentence Structure, and the Multiplexer, would FIFO, and buffer, the
data, using internal registers, since NEMA updates only happen about
once a second anyway.

maybe our Multiplexer Friend, Miendert SP could enlighten us on the
subject, if he is still reading the newsgroup.....

--
Bruce in alaska
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