Specifications

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5.12.3 Retrieving logger files
Before removing the flash card or even removing the power it is important that the logger is
stopped. To stop the logger, use the console command stoplog. Refer to the chapter on the
console for more information. The LED light next to the flashcard insert lights up when writing
actions take place on the card.
Now the power may be disconnected and the flash card ejected. Insert the flash card into a
flashcard reader or a PCMCIA adapter and copy the collected data to your hard disk. Sometimes
a few files or even the whole flash card can not be read. Several causes may result an invalid
flash card or corrupted files, e.g. exhausted batteries at the end of the operational life,
disconnecting the power before stopping the logger or a firmware crash during a write-
operation. Windows provides a utility (check disk) to repair the flash card and sometimes to
restore the corrupted files. Follow the procedure below.
Repairing a compact flash module
(1) First save a copy of all readable files to your hard disk.
(2) Either invoke the DOS prompt or go to “Start”, select “Run” and type “cmd<enter>” or
“command<enter>”.
(3) Type “chkdsk <DRIVE> /F. For example:
chkdsk E: /F
(4) The check disk-utility will perform a disk scan, repair the FAT and print a report.
(5) Copy all newly repaired files to your hard disk.
(6) After repair it is also possible to erase all files, should you redeploy this flash card.
5.12.4 Logger file organization
The logger stores data in a message-like structure, i.e. with a header, message identification,
time tag, date, the data in question and finally a checksum. Spectral/system-file data and
displacement data each are packed in their own specific message. On a larger scale several
messages of the same type are combined into one file, where one file covers one day or one
month. Eventually, the logger contains only 3 types of files:
(1) Raw displacement files (*.RDT)
(2) Spectrum/system files (*.SDT)
(3) Event log file (HISTORY.DOC)
Refer to the correspondingly named subsections for more information.
Time and date in the logger are obtained automatically from the GPS receiver, which is
standard on all Waveriders. No manual setting or calibration of the internal clock is needed.
The buoy automatically reserves sufficient space on the flash card for 3 years of
continuous event, error and spectrum/system-file logging. The remaining space on the flash card
is used for displacement data. Table 5.12.1 shows the relationship between the size of the
flashcard and the available storage capacity.
Flashcard sizes up to 2 GB can be handled.