
April
2018
Pathfinder DVL Guide
Page 154
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
Choosing a Data Format
The Pathfinder can output data in several user selectable formats using the PD command (see
). Depending on the output format selected, data will be either binary or ASCII text.
Binary Output Data Format
Use the binary format (CFxx1xx) when recording/processing Pathfinder data on an external device. The
binary format uses less storage space and has a faster transmission time than the Hex ASCII format. A
dumb terminal is of little use in binary format because the terminal interprets some of the data as control
characters.
All of TRDI’s software supports binary PD0 formatted data only.
Hexadecimal-ASCII Output Data
Use the hexadecimal-ASCII (Hex ASCII) format (CFxx2xx) when viewing raw Pathfinder data on a com-
puter/dumb terminal. This format uses the standard ASCII codes for 0 through F to represent numeric
values as hexadecimal digits. Other standard ASCII characters (text) and control commands (carriage re-
turn, line feed, end of file, etc.) are interpreted normally. In the Hex ASCII mode, the Pathfinder sends
data in one line of ASCII characters. There are no carriage returns and/or line feed sequences (CR/LF)
sent from the Pathfinder. The CRT provides a CR/LF after 60 characters.
Hex ASCII PD0 data is not supported by TRDI’s software.
When operating in HEX mode, all console text appears in HEX - including the prompt ">" (HEX
"3E") and any additional commands that are typed.
Individual parameters within a data string may be enabled / disabled. All binary output formats have the
option of outputting data in HEX-ASCII instead of true binary using the CF command (see
). HEX-ASCII is an ASCII representation of the binary data. Binary output formats include
PD0
,
PD4
,
and
PD5
. Text output formats include
PD6
.
Deciding on which format to use depends on the needs of the deployment. The following describes the ba-
sics of the formats available.
•
PD0
–
PD0
is Teledyne RD Instrument’s standard format.
PD0
is a binary output format. It provides
the most information possible including a header, fixed and variable leader, bottom track, and water
profile information. The fixed and variable leader is a recording of time, DVL setup, orientation, head-
ing, pitch, roll, temperature, pressure, and self-test diagnostic results. Data fields to be output are
user selectable.
•
PD4
–
PD4
is a binary output format of bottom track speed over the bottom, speed through the water,
and range to bottom information.
•
PD5
–
PD5
is a superset of
PD4
and includes information on salinity, depth, pitch, roll, heading, and
distance made good.
•
PD6
–
PD6
is a text output format. Data is grouped into separate sentences containing system attitude
data, timing and scaling, and speed through the water relative to the instrument, vehicle, and earth.
Each sentence contains a unique starting delimiter and comma delimited fields. If
PD6
is selected,
there is no data written to the recorder.
•
PD13
-
PD13
outputs similar to
PD6
, except it adds Pressure and Range-to-bottom for all four beams,
and omits the System Health Monitor Data line.