Operator's guide
4.2 Disk
This page allows you to change how the DCM will use its hard disk, and what
data it will record on it. If you want to check that the hard disk is working,
explore its contents, or format it, you should use the Disk tools page instead (see
below.)
The first three options allow you to specify formats in which the DCM should
record data. There are three options: gcf, miniSEED and sac. The latter two are
provided for archival purposes, and are not optimised for data transfer; Güralp
digitizers and software all work natively with GCF, the Güralp Compressed
Format. The DCM allows you to record in several formats simultaneously, if
you wish; you should make sure that you have the capacity to store, or the
bandwidth to transfer, all the data the DCM will produce in each format you
have enabled.
One file will be prepared for each format (or format and stream, for those
formats which deal with single streams) every three hours. The DCM will
always start a new file if it is power cycled; the aborted file will still be valid.
Files are not immediately written to the disk, but into Flash memory; the
options disk.usagemode and disk.writeinterval, below, control how often the
DCM flushes new data to the disk, and what it will do if the disk becomes full.
disk.recordas.gcf : Set this to yes to have the DCM record Güralp Compressed
Format data files.
disk.recordas.miniseed : Set this to yes to have the DCM record files in
miniSEED format.
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