YSI SonTek ADVField, Техническая документация инструкция

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SonTek/YSI
ADVField/Hydra Operation Manual (September 1, 2001) 97
Appendix 2. ADVField Autonomous Data Output Formats
This appendix describes the various formats of the output data generated by the ADVField during
autonomous
data collection. The format is the same for all ADVField configurations and models.
See Appendix 1 for the output data formats generated during
real-time
data collection.
During autonomous data collection, the ADVField sends ASCII burst header data via the serial
port and binary output data to the internal recorder.
•
Section A2.1 describes the real-time ASCII output format to the serial port.
•
Section A2.2 describes the real-time binary output format to the internal recorder.
A2.1. Autonomous Output Data – ASCII Format (to Serial Port)
During autonomous data collection, the ADV sends burst header data via the serial port at the
start of each burst. The header is always sent in ASCII format. No additional data is sent over the
serial port during autonomous deployments. Below is a sample of the burst header output, fol-
lowed by a description of the data shown on each line.
0013 1 2001 02 03 14 30 51
4 0 1000 1200 2 23 15209 -1 -1
0 0 0 0 219 220 219 220 24 24 24 219 199 240 0 92 0 0 0 0
Line 1: Serial number, burst number, year, month, day, hour, minute, second. Note that the time
recorded represents the start of the first sample in the burst.
Line 2: Velocity range, spare byte (set to 0), sampling rate (0.01 Hz), samples per burst, coordi-
nate system (1=XYZ, 2=ENU), recorded-data byte (see below), sound speed (0.1 m/s),
probe distance to boundary, sampling volume distance to boundary (see below)
Line 3: System diagnostic data - the only value of interest to the user is the 16
th
item on this line,
which is battery voltage in units of 0.2 V (e.g., output of 92 = 18.4 V)
Recorded-data byte
– This parameter uses one byte to identify the user-selected data recording
options. Each item sets a bit to 1 if enabled or 0 if disabled. With bit 7 as the MSB and bit 0 as
the LSB: RecordCTD (or RecordLISST) uses bit 7; RecordExtPress=bit 6; RecordExtSensor=bit
5; RecordStat=bit 4; (bit 3 not used); RecordSensor=bit 2; RecordCompass=bit 1; RecordAmp-
Corr=bit 0. Examples: a value of 23 (binary 11110111) means all data recording was enabled; a
value of 2 (00000010) means that only RecordCompass was enabled. See Table 23.
Distance-to-boundary
data is reported in two values: distance from the probe tip to the boundary
and distance from the center of the sampling volume to the boundary. Both are output with the
burst header in units of 0.1 mm. A value of -1 indicates that the boundary was not detected.
A2.2. Autonomous Output Data – Binary Format (to Internal Recorder)
Data recorded on the internal recorder during
autonomous
deployments use a different file format
than that used for
real-time
data collection. The reasons for this are listed below. For a descrip-
tion of the sampling strategies used by the autonomous ADVField, see §1.3.
•
Additional information is needed to describe ADV autonomous data collection.
•
Data must be periodically referenced to the real-time clock. In real-time collection, the data
rely on the sampling clock; this clock is not accurate enough for long-term deployments.
•
Different data formats are required to support multiple-burst sampling.
•
Data recording options have been included to optimize storage requirements.