
Athena Data Files
Sept 20, 2002

Data handling for the ship's standard instrumentation is accomplished by the Athena data collection, logging, display and distribution system.  The capabilities of this system are extensive and it can be expanded to incorporate sensors provided by the science party.  All laboratories and many potential sensor locations have cabling installed to facilitate expansion of this type.

The Athena system generates data files of two different types: 1) asynchronous single-item-per-line time stamped ASCII and 2) synchronous multi-item-per-line comma delimited (Excel).  A single file of the first type is always created containing data items logged at the time interval specified by the Athena configuration.  Each line starts with a data identifier followed by the date and time given in the form used by Visual Basic (number of days since Dec. 31, 1899; the 31st is day #1) and then the time in normal human readable form.  These values are followed by the data terminated with a <cr><lf>.  Log files are normally created at midnight and the name of the file provides ship and creation date information with a ".dat" extension.  The first line of the file provides ship, date and initialization time information. All lines after the first contain data as shown in the following example taken from an OCEANUS file named "OC020915.dat".

Athena data file,  Sun 15/Sep/2002 00:00:11
IMET_HRH  	37514.00031	00:00:26	99.253   19.819
IMET_SWR  	37514.00031	00:00:26	0.1
IMET_BPR  	37514.00031	00:00:26	1021.66
IMET_PRC  	37514.00032	00:00:27	-0.00    0.00   7.69
SSTMP     	37514.00032	00:00:27	+24.6322
SSCND     	37514.00032	00:00:27	+50.0594
HEHDT     	37514.00032	00:00:27	$HEHDT,025.7,T
PKEL99    	37514.00034	00:00:29	$PKEL99,15.01,00.00,1500
Salinity  	37514.00050	00:00:42	33.0489
SSV       	37514.00050	00:00:42	1531.3961
TWind     	37514.00050	00:00:43	2.7932 181.6
GPS       	37514.00051	00:00:44	$GPGGA,000043.043,4131.4319,N,07040.3348,W,
3,08,1.0,026.0,M,034.4,M,,*75,$GPGXP,000043,4131.4319,N,07040.3348,
W*5D,$GPGLL,4131.4319,N,07040.3348,W,000043.043,A*21,$GPVTG,341.5,
T,357.1,M,000.0,N,000.0,K*4D
IMET_WND  	37514.00083	00:01:11	1.14  -2.55   2.8  3.3  2.4  161.2  0.0 0  4
IMET_HRH  	37514.00100	00:01:26	99.253   19.818
IMET_SWR  	37514.00100	00:01:26	0.1
IMET_BPR  	37514.00101	00:01:26	1021.71
IMET_PRC  	37514.00101	00:01:27	0.00    0.00   7.69
SSTMP     	37514.00102	00:01:27	+24.6304
SSCND     	37514.00102	00:01:28	+50.0560
HEHDT     	37514.00102	00:01:28	$HEHDT,025.6,T
PKEL99    	37514.00102	00:01:28	$PKEL99,15.00,00.00,1500
Salinity  	37514.00119	00:01:42	33.0512
SSV       	37514.00120	00:01:43	1531.3979
TWind     	37514.00120	00:01:43	2.8356 183.7
GPS       	37514.00120	00:01:43	$GPGGA,000142.043,4131.4306,N,07040.3343,W,
3,08,1.0,028.3,M,034.4,M,,*7D,$GPGXP,000142,4131.4306,N,07040.3343,
W*58,$GPGLL,4131.4306,N,07040.3343,W,000142.043,A*24,$GPVTG,341.5,
T,357.1,M,000.0,N,000.0,K*4D
IMET_WND  	37514.00152	00:02:11	1.06  -2.63  2.8  3.5  2.4  165.3  0.0  0  4
IMET_HRH  	37514.00170	00:02:26	99.253   19.804
IMET_SWR  	37514.00170	00:02:26	0.0
IMET_BPR  	37514.00170	00:02:26	1021.70
IMET_PRC  	37514.00170	00:02:26	0.00    0.00   7.70
SSTMP     	37514.00171	00:02:27	+24.6314
SSCND     	37514.00171	00:02:27	+50.0593
HEHDT     	37514.00171	00:02:27	$HEHDT,025.7,T
PKEL99    	37514.00173	00:02:29	$PKEL99,15.02,00.00,1500
Salinity  	37514.00188	00:02:42	33.0511
SSV       	37514.00189	00:02:42	1531.3987
TWind     	37514.00189	00:02:42	2.5863 181.0

Note: the GPS data in the above example contains line-formatting characters that are not normally present in the real data files.  The Athena program concatenates multi-line data, replacing line termination characters with commas.  <cr><lf> characters are only present at the end of each data line.

The "Excel" format file uses the same naming convention except that the extension is a three-digit number.  Excel files are started at midnight and begin with a header line that identifies the data items in each of the following comma delimited columns.  The content of these files can be changed by a number of methods and if this is done, a new file is created having a new file name extension number and header line.  The rate at which data is added to the Excel files is controlled by an entry in the Athena configuration file.  Each line begins with a time-stamp and contains the most recent data available at the time of the entry.  Data is not repeated; if new data is not available when a line is to be added, the corresponding column is left blank.  The following is an example taken from the file "OC020915.000".
  
Time (hhmmss), SSTMP, SSCND, Gyro, Salinity, Wnd_Spd, Wnd_Dir, Depth12, 00:00:25, +24.6304, +50.0582, 025.7, 33.0499, 2.6768, 185.4, 15.01, 
00:01:25, +24.6318, +50.0601, 025.6, 33.0503, 2.7932, 181.5, 15.02, 
00:02:25, +24.6318, +50.0597, 025.7, 33.0500, 2.8356, 183.7, 15.01, 
00:03:25, +24.6333, +50.0579, 025.7, 33.0475, 2.5863, 181.0, 15.03, 
00:04:25, +24.6334, +50.0609, 025.7, 33.0497, 2.4399, 181.8, 15.06, 
00:05:25, +24.6339, +50.0577, 025.6, 33.0469, 2.6613, 178.1, 15.01, 
00:06:25, +24.6337, +50.0578, 025.7, 33.0472, 2.4955, 179.5, 15.01, 
00:07:25, +24.6322, +50.0605, 025.6, 33.0503, 2.7171, 181.5, 15.01, 
00:08:25, +24.6325, +50.0618, 025.7, 33.0510, 3.0276, 179.2, 15.03, 
00:09:25, +24.6325, +50.0581, 025.7, 33.0483, 2.7602, 180.6, 15.04, 
00:10:25, +24.6309, +50.0587, 025.7, 33.0499, 3.0366, 178.9, 15.03,
00:11:25, +24.6329, +50.0584, 025.7, 33.0482, 3.4708, 178.2, 15.02, 

Metadata

The Athena system also generates a metadata file (MetaData.txt).  This is a single text file containing information on the various data sources listed by the sensor designator used in the header information of the other two file types.  Hopefully this file contains enough information to make effective use of the data contained in the other files (i.e. format, units, sensor type, etc.). 

  

Legacy Athena data files
 
WHOI began using the original DOS based Athena data collection and logging system in 1990.  This was replaced with the present Windows based Athena software in 2000 but some of the applications developed for use with the original system persist and therefore software has been written to construct data files having the older format.  Typically, this code runs on a computer obtaining data from the Windows based Athena via UDP broadcasts and uses the data in conjunction with legacy applications.  If constructed, files of this format are available during the cruise on Linus in /home/data/Athena/asciilog and they are placed on the data CD in the Atlantis/Athena90 directory.
 
A new Athena90 data file is created each night at midnight (GMT).  Filenames are based on the date.  For example, the following name would be assigned to a normal data file created on June 20, 1997: "AT970620.001"

The content of the file is given by information in the header.  Each line begins with a three digit identifier followed by a "|" character indicating the start of the data entry.  Entries are made in blocks, each of which contains a complete set of the data being logged to this file, all collected at the time of the entry (usually designated by an 001| JSECONDS and/or 003| CTIME time stamp data item).  The date may be included in each data block but normally this is provided in the header.  A sample legacy Athena data file is provided below:

R/V ATLANTIS DATA LOG - 1 minute log file
Primary Data File (ASCII)
07/09/97   00:00:01
Julian Seconds = 13087699201
ATHENA V5.2

001| JSECONDS  Date & time (Julian seconds)
002| CDATE     Computer date
003| CTIME     Computer time
011| GYRO      Ship's heading (Gyro)
018| MBYTE1    MetraByte module #1
024| SSCND     Sea surface conductivity (mmho/cm)
025| SSTMP     Sea surface temperature (C)
041| GPS_COG   GPS course over ground
044| GPS_SOG   GPS speed over ground
045| GPS_TP    GPS time & position

001| 13087699230
002| 07/09/97
003| 00:00:30
011| 187.0,T
018| +03802.70
024| +41.5004
025| +20.0899
041| 178.8
044| 005.9
045| 000027.612,3716.4251,N,03215.9971,W,3

001| 13087699290
002| 07/09/97
003| 00:01:30
011| 188.5,T
018| +03807.50
024| +41.5358
025| +20.1260
041| 179.6
044| 006.0
045| 000127.612,3716.3242,N,03215.9939,W,3

001| 13087699350
002| 07/09/97
003| 00:02:30
011| 189.5,T
018| +03808.40
024| +42.1142
025| +20.5196
041| 180.2
044| 005.6
045| 000227.612,3716.2273,N,03215.9916,W,3

001| 13087699412
002| 07/09/97
003| 00:03:32
011| 190.2,T
018| +03810.20
024| +42.1768
025| +20.6000
041| 178.1
044| 005.9
045| 000329.612,3716.1277,N,03215.9905,W,3

001| 13087699470
002| 07/09/97
003| 00:04:30
011| 191.7,T
018| +03815.20
024| +41.8013
025| +20.7400
041| 179.8
044| 005.8
045| 000427.612,3716.0355,N,03215.9879,W,3

001| 13087699532
002| 07/09/97
003| 00:05:32
011| 192.0,T
018| +03817.2a
024| +42.1537
025| +20.6091
041| 179.7
044| 005.6
045| 000529.612,3715.9353,N,03215.9894,W,3





