Guralp Systems CMG-DM24 - Manual (Page 20)

CMG-DM24
This feature is particularly useful for autonomous installations: after
the digitizer has been retrieved from a field experiment, simply
powering it up with a prepared disk attached will make it transfer all
the data it has recorded during the experiment.
While the FireWire interface is active, it will consume about 200 mA
of power (from a 12 Volt supply). If you interrupt a transfer whilst it is
in progress, the digitizer will re-boot and will not mark data as
downloaded. Because of this, the next time you transfer data, some
will be duplicated. You will not, however, lose any data.
Downloading over the serial link
To download data over the serial link:
1. Open the digitizer's console. To do this using Güralp Systems'
Scream! software, right-click on the digitizer's icon (once it
appears) and select Terminal.... From a Güralp DCM, issue the
command minicom -n port-number.
2. If you want to download all data held in the Flash memory,
issue the command
ALL-FLASH ALL-DATA DOWNLOAD
3. Alternatively, select a particular set of streams, sample rates and
times to download using the STREAM, S/S, FROM-TIME and TO-
TIME commands, and finish with DOWNLOAD. See Section 5.9,
page 77, for more details.
4. Issue the GO command to start transferring data. If you are
using Scream! or a DCM, closing the terminal session will have
the same effect.
3.5 Reading DM24 disks
When the DM24 saves data onto a FireWire disk, it uses a special
format called DFD.
You can read this data into a PC using Scream! or the gcfxtract
utility, which is freely available from the Güralp Systems Web site.
Linux and Solaris command line utilities are also available for reading
data from a DFD disk.
The DFD format is not the same as that used by the Güralp Systems
DCM data module, which uses a FAT32-compatible journalling file
system.
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