Guralp Systems CMG-CD24 - Manual (Page 43)

Operator's Guide
You can retrieve blocks from a digitiser in FILING mode by connecting
to its terminal interface and issuing commands such as FLUSH, or
through Scream! (see below).
Heartbeat messages
When in FILING mode, a digitiser transmits “heartbeat” messages over
its data port. These short messages take the place of data blocks, and
ensure that programs such as Scream! know that a digitiser is present.
You can change the frequency of heartbeat messages from Scream!'s
Control window, or with the command HEARTBEAT.
You can tell Scream! to download new data automatically whenever it
receives a heartbeat message from a digitiser in FILING mode. This is
useful, for example, in autonomous installations connected by
intermittent modem links. To enable this feature:
1. Choose File Setup... → from Scream!'s main menu, and navigate
to the Recording pane.
2. Check Auto-download on heartbeat.
3. Click OK.
Using FILING mode with Auto-download on heartbeat ensures that
Scream! receives all new data whenever it can, regardless of the
configuration of any devices between you and the digitiser.
3.2.5.3 DUPLICATE
Syntax: DUPLICATE
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