CMG-DCM
3. Connect the NETWORK socket to a computer as described in
Section
2.4, “Connecting to a local network”
and perform any necessary
configuration of the DCM and digitizer. You will be prompted for a
username and password: log in as
root
and use the password supplied
by Güralp Systems.
4. The DCM will immediately begin recording data into Flash memory as
it is received, and every so often data will be moved onto the internal
hard disk. At this point you can leave the DCM running without
assistance.
Data is stored in the Flash memory as a number of files in Güralp
Compressed Format (GCF) unless you have specified another option.
Once the memory becomes 75% full, files are automatically moved to
the hard disk until it is less than 50% full. (See
Section 6.1, “File
systems”
for details of the algorithm used.)
You can check that the DCM is receiving data either by monitoring the
Summary page of the on-board Web interface (see
Section 5.7,
“Summary”
), or from a command prompt using the command
gnblocks
port-number
to find the number of GCF blocks received so far on a port. To see the
number of blocks recorded on all ports, type
gnblocks
5. If the internal hard disk is missing or becomes full, and you have chosen
the USB host option, the DCM will automatically look on the USB
interface for an external USB mass storage device.
6. To replace the internal hard disk, unclip the cover of the DCM and hold
down the lever button to bring the disk out from its housing.
22
Issue A
