6- Communication; Heading Measurement Messages - ADVANSEA COMPAS S400 Manuel Utilisateur

6- Communication

The advanSea Compass is equipped with a serial 0 / 5V output
used to broadcast sensor measurements using the standardized NMEA
0183 Version 4.1 protocol. The communication speed of this output is set
to 4800 bauds.
Upon power up, an identification frame $ PADVV is issued. This
proprietary frame will allow to check the product firmware version.
$PADVV,Compas advanSea V1.0,17/09/2018 17:17:26*04<CR><LF>
Product designation / Firmware version / Date and time of compilation

6.1- Heading measurement messages

The magnetic heading is given by the frame $ HCHDG at the rate
of 5Hz
$HCHDG,147.8,,,,*48<CR><LF>
Magnetic heading
To ensure compatibility with older NMEA receivers, the advanSea
Compass also broadcasts its heading measurement in the $HCHDM frame
every time the HDG (5Hz) frame is broadcast.
$HCHDM,147.8,M*23<CR><LF>
Magnetic heading
The summary table below shows the occupancy rate of the available
bandwidth at 4800 bauds with the corresponding transmission rates.
Frame type Description
$PADVV Identification
$HCHDG Magnetic
heading
$HCHDM Magnetic
heading
18
Number of Emission rate
characters
(with
checksum)
52
21
19
Total
Transmission
time (@ 4800
bauds)
0 Hz 108,3 ms
5 Hz 43.7 ms
5 Hz 39,6 ms
83,3 ms
Bandwidth
occupation
0 %
21,8%
19,8%
41,6%