Guralp Systems CMG-5TD User Manual
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Operation
Separate from these modes are buffering modes, which tell the unit what to do
when its Flash memory becomes full: either
•
carry on, overwriting the oldest data held, or
•
stop writing and switch the digitizer into DIRECT mode.
You can switch between filing modes in Scream! by right-clicking on the
digitizer and clicking on Control..., then navigating to the Data Flow pane:
To choose a transmission or buffering mode, choose options from the
Transmission Mode or Buffering drop-down menus, and click Apply. An
explanation of the chosen mode is displayed beneath each menu. The
following sections also explain the filing modes available.
The Buffering legend also displays the amount of Flash memory present in
your digitizer. In the example screen-shot above, this is 64 Mb.
To clear the Flash memory of the digitizer, click the Reset-flash button. You
will be asked for confirmation before the memory is cleared.
At the bottom of the tab is a line describing the current state of the digitizer's
memory pointers. You can use this line to check that data are being written
into memory. Select Auto-Refresh to make the line update automatically.
5.9.5.1 DIRECT
Instructs the digitizer not to use Flash memory for storage. Instead, all data
are transmitted directly to clients. An instrument in DIRECT mode still
honours the GCF Block Recovery Protocol: a temporary RAM buffer always
holds the last 256 blocks generated, and if a client fails to receive a block it
can request its retransmission.
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Issue D - April 2013