Athena Data Files Jan 1, 2003 Data handling for the ship's standard instrumentation is accomplished by the Athena data handling system. The capabilities of this system are extensive and it can be easily configured to incorporate sensors provided by the science party. All laboratories and many potential sensor locations have installed cabling 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 2) synchronous multi-item-per-line comma delimited ASCII (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. Time values are GMT unless the file header specifies a different time zone. These values are followed by the data terminated with . Log files of this type have a name extension of ".dat" and are normally created at midnight. The name of the file provides ship and creation date information. 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. 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 - normally entries are made once per minute. 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 line and column 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 (Athena90) 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 the Linus computer in /home/data/Athena/asciilog and they are placed on the data CD in the /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