Guralp Systems CMG-DM24 - Manual (Page 25)

Operator's guide
section 3.3, on page 15. As no contiguous streams are sent via the
serial port in these modes, nothing will be written to the USB device.
To record data to a USB device, the system should be configured in
DIRECT or DUPLICATE mode – in DUPLICATE+REUSE mode the
DM24 will always have the last 64Mb or more of data in its internal
flash – the firmware does not currently support transferring data from
the DM24 internal flash to a USB device.
Formatting a USB device
If you wish to use a USB device it must be formatted with 16 Kilobyte
clusters. In Windows 2000, XP and Vista open a command prompt and
type:
format e: /fs:fat32 /a:16k
replacing e with the letter of the drive which you wish to format.
Directory structure
The system creates the following directory (folder) structure:
The main directory is \GURALP
Beneath this is a sub-directory named after the DM24's system ID (e.g.
GSLA) within which will be a further sub-directory for each stream the
system is configured to produce. For example:
C838Z2 tap2, vertical component at selected sample rate
C838M8 vertical component mass position
C83800 the digitizer's status stream
Data for each stream is recorded as files within the corresponding sub-
directory. The file name is simply the date and time of the first sample
in the file, given in the format YYMMDDHH.xxxx
For example:
08102314.gcf 2008 Oct 23 14:00 – data file
08102312.txt 2008 Oct 23 12:00 – status/text file
The amount of data in each file (granularity) depends on both the
stream sample-rate and type. It can be configured using the
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