"Matti Raustia" wrote in message
...
My ST50 Multi outputs a broken NMEA sentence: wind info
(VWR). It splits both sentences as two sentences like this:

$IIVWR,113.,R,,,,,,
$IIVWR,,,,,,,03.0,N


Technically speaking, the sentences are not broken at all. Raymarine just
chose to output the direction and speed in two separate sentences, leaving
the unused fields blank. This is completely according to the NMEA specs,
however stupid it may seem. You could even go one step further and blame
SeaClear because they omit to keep the last received value in a sentence
for, say, 10 seconds before assuming the info is not present. If they did it
that way, SeaClear could then combine the wind direction and speed and do
something useful. Since SeaClear is a free program, your best bet is to
write the author and explain the problem to him. This should be very easy to
fix for him.

Because the wind speed and direction are contained in two different SeaTalk
datagrams, the Raymarine converter just translates each datagram into an
NMEA sentence, where the speed is averaged over a longer period, thus the
lower frequency of the sentence. In my multiplexers (www.shipmodul.com), I
collect both datagrams (speed and direction) and output one NMEA sentence
with both fields filled.

Meindert