SeaTrac Serial Command Interface Reference
Page 133
8.4.8.
CID_NAV_BEACON_POS_UPDATE
The CID_NAV_BEACON_POS_UPDATE message is generated when the beacon receives
acoustic information sent from another beacon with the
command.
On reception of the message, the acoustic payload is decoded and the transmitted
Northing/Easting/Depth position for the specified beacon is output from the serial port.
The connected host system may then use this information to update tracking tables/records as
required for all other beacons in the network being interrogated by the USBL controller.
Subsequent reception of a
command allows all relative NED
coordinates to become world reference through the specification of the USBL origin
latitude/longitude position.
This message is a status message that may be sent by the beacon at any time (not in
response to a command message) depending on acoustic activity triggering a
transceiver event.
Response Message Parameters
Parameter Type Description
MSG_ID
identification code
(CID_NAV_BEACON_POS_UPDATE)
ACO_FIX
A Fix structure containing information relating to
signal from the beacon sending data.
This will not contain range or position information,
but will contain the message SRC_ID.
BEACON_ID
The ID code of the beacon this position refers to.
Valid values are form 1 to 15.
NB: This ID code does not necessarily refer to the
local beacon (although it may).
POSITION_EASTING INT16
The
Easting
distance component of the beacon
specified by BEACON_ID relative to the USBL head
(or sender of this message).
This value must be encoded in deci-meters, so
divide the value by 10 to obtain a distance in
metres.
POSITION_NORTHING INT16
The
Northing
distance component of the beacon
specified by BEACON_ID relative to the USBL head
(or sender of this message).
This value must be encoded in deci-meters, so
