SeaTrac Serial Command Interface Reference
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5.
Serial Protocol
Communications between a SeaTrac Beacon and controlling device (such as a PC or embedded
system) take the form of Command Messages sent to the Beacon, and Response (or Status)
Messages received back from it.
All Command Messages issued to the Beacon are acknowledged by a Response Message, and
occasionally Status messages are generated by the beacon in response to system events (such
as message reception etc).
5.1.
Serial Settings
Messages are sent over the RS232 serial link with the following settings…
115200 Baud Rate (the baud rate can be adjusted via the beacon settings – see the
Beacon User Manual, or
command for further details).
8 Data Bits
No Parity
1 Start Bit
2 Stop Bits
No handshaking / flow-control
5.2.
Message Format
For ease of implementation and diagnostics, all messages are transmitted using ASCII encoded
characters.
Command and Response messages share the same message structure, as shown in the
diagrams below…
Command Message (from PC to Beacon)
#
1 char
CID
2 chars
Command Payload
multiple of 2 chars
CSUM
4 chars
<CR><LF>
2 chars
Response Message (from Beacon to PC)
$
1 char
CID
2 chars
Command Response
multiple of 2 chars
CSUM
4 chars
<CR><LF>
2 chars
