gadgetPool SeaTalk NMEA, Installation And Operation Manual

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NMEA Input
SeaTalk Output
NMEA -> SeaTalk
translation
SeaTalk Output
The converter periodically checks if any new data has arrived from NMEA, which have to
be sent to SeaTalk. New data is written to the SeaTalk bus only if the bus is not in use by
any other instrument. If the bus is in use, the converter waits for a while, and tries again.
Collision detection
Every single bit sent out to the SeaTalk bus is read back again and checked for successful
transmission. If the transmission was corrupted, the transmission is stopped immediately.
When the bus becomes free, the transmission will be started again.
At this time the following SeaTalk datagrams can be sent
00 Depth
10 Wind angle
11 Wind speed
20 Speed through water
25 Total & Trip mileage
27 Water temperature
30 Lamp intensity
50 Latitude
51 Longitude
52 Speed over ground
53 Course over ground
54 Time
56 Date
82 Target Waypoint Name
85
Navigation to Waypoint information
89 Compass ST40 heading
Same type of Data on NMEA & SeaTalk
Information available from like instruments on both Busses ( SeaTalk & NMEA ) are not
converted.
Example:
We have a depth sounder on the SeaTalk Bus and another depth sounder on the NMEA
bus.
So, on both sides depth information is available.
In this case no depth information in transferred from one bus to the other.
( If depth information is not updated within 30 sec. on one bus, sending to the other bus is
activated again. )