Guralp Systems CMG-CD24 - Manual (Page 45)

Operator's Guide
FIFO mode will consider a data block successfully transmitted once it
has received an acknowledgement from the next device in the chain.
If there are several devices between you and the digitiser, you will
need to set up the transmission mode for each device (if applicable) to
ensure that data flow works the way you expect.
Like all the transmission modes, FIFO mode does not delete data once
they have been transmitted. You can still request anything in the
Flash memory using Scream! or over the command line. The only way
data can be deleted is if they are overwritten (in the RECYCLE
buffering mode, see below) or if you delete them manually.
3.2.5.5 ADAPTIVE
Syntax: ADAPTIVE
Instructs the CD24 to transmit current blocks to clients if possible, but
to store all unacknowledged blocks in the Flash memory and re-send
them, oldest first, when time allows. ADAPTIVE mode is best suited
for “real-time” installations where the link between digitiser and client
is intermittent or difficult of access.
If the communications link is only marginally faster than the data rate,
it will usually be busy transmitting real-time data. Thus, it may take a
while for the digitiser to work through the missed blocks. In this case,
and if your client supports it, you may prefer to use the Block
Recovery Protocol to request missed blocks where possible.
Some software packages (most commonly Earthworm) cannot handle
blocks being received out of time order. If you are using such a
package, ADAPTIVE mode will not work, and may crash the software.
3.2.5.6 DUAL
Syntax: DUAL
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