Guralp Systems CMG-6TD User Manual

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Installing the 6TD

3. Issue the command FLUSH

This will download all data from the 6TD that it has not already

transferred. If you want to transfer the entire contents of Flash
memory, use the command FLUSHALL. For more details, see section

4. Close the terminal session. If you are using Scream! or an EAM, the

6TD should start transmitting immediately. Otherwise, you may need
to issue the command GO to start transferring data.

4.13.1 Reading 6TD disks

The 6TD uses a special disk format, DFD, for recording data. This format is

also used by other Güralp digitisers such as the DM24.

You can read this data into a PC using Scream! or the gcfxtract utility,

which are freely available from the Güralp Systems Web site.

Note: The DFD format is not the same as that used by the Güralp

Systems EAM data module, which uses an ext2, ext3 or a
FAT32-compatible journalling file system.

Güralp Systems can provide fully-tested disks with FireWire and USB

connectors. Alternatively, a third-party FireWire disk may be used (although
compatibility is not guaranteed).

To read a disk using gcfxtract:

1. Attach the disk to your computer. You can use FireWire, USB, or any

other interface supported by your computer and the disk.

2. Run gcfxtract and select the required disk from the drop-down list,

then click

Gcfxtract will scan the disk and display all the streams it finds in the
selection area below. For each stream, the Stream ID and the number

of blocks found are shown.

This operation requires roughly 12 Mb of available memory for every

Gb of space on the disk. If you have a very large disk, your computer
may have to use its hard disk to make enough space. This will slow

down scanning considerably.