Yacht Devices YDEN-02 Series, User Manual

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3.2. Syntax of NMEA 2000 (RAW protocol) filters
You should be familiar with the NMEA 2000 Standard (can be purchased
from National Marine Electronics Association, www.nmea.org ) to operate with
NMEA 2000 filters.
These filters actually contain pairs of 29-bit message identifiers and a mask.
The identifier is compared by processing the NMEA 2000 message identifier
and the second value (mask) defines the comparison concerning which bits
are significant. The identifier contains a PGN (Parameter Group Number, described
in NMEA 2000 Standard) and a source device address. You can use decimal
and hexadecimal numbers (which start with a 0x prefix).
To simplify defining filters, it is also allowed to set filters using PGN only. The filter
string contains records separated by comma. Records contain an identifier and mask
separated by space, or a PGN number.
Example of correct filter:
0x1FD0700 0x1FFFFFF, 130310, 1 255, 130311
This filter matches with messages with PGN 130311 (0x1FD07) sent by the device with
address 0, PGN 130310 (sent by any device), messages sent by a device with address 1
(«1 255» is another form of the record «0x0000001 0x00000FF»), and PGN 130311
(sent by any device).
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