SeaTrac Serial Command Interface Reference
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increased (due to reduced mechanical damping).
Taking the above note into account, development and testing of the beacons in air is still
possible so long as the developer is aware of the risks.
Beacons can be placed on a bench about 30cm to 50cm apart and should communicate
acoustically with each other, although sometimes it’s more reliable to use clamp-stands to hold
them away from the surface of the desk.
Developers should also be aware that in close proximity in air, there can be electro-magnetic
cross-talk and triggering between beacons (and their cabling) rather than successful receipt of
acoustic messages.
If the velocity-of-sound value for the transmitting beacon is manually specified to be
around 340ms
-1
, then ranges accurate to around ±20mm should be obtained.
However, accurate and repeatable USBL positioning is not possible in air due to the
geometry of the USBL receiver array and the wavelength of sound in air.
4.3.
Reading Beacon Information
For new users, it is recommended that the first activity attempted is to read and validate the
beacon information command.
First, connect a beacon to the computers serial port and run a serial terminal
application to establish a connection (several free “serial terminal” applications are
available to download from the internet).
If required set the terminal application to echo characters typed locally and append
line-feeds to carriage-return characters (so a <CR><LF> character pair is sent at the
end of messages).
When the beacon is powered up, a series of information messages should be displayed
in the terminal window along the lines of…
SEATRAC X-SERIES BEACON
Copyright (c) 2014 Blueprint Design Engineering Ltd. All rights reserved.
For further information, visit http://www.blueprintsubsea.com
Firmware Part BP00913, Version 1.0, Build 1915
Device Information...
Hardware Part Number = BP00795
Hardware Part Revision = 1
Hardware Serial Number = XXXXXX
Hardware Flags = 0x00000000
Hardware EUI48 = XX:XX:XX:XX:XX:XX
Bootloader Valid = 1
Bootloader Part Number = BP00912
Bootloader Version = v1.0.361
Bootloader Checksum = 0xBFC5FAB7
Application Valid = 1
Application Part Number = BP00913
