4 baud rates, 5 data flow – Guralp Systems CMG-5TD User Manual

Page 23

Operation

5.9.4 Baud rates

This tab allows the setting of the line speed for the main serial output.

It is possible to set different rates for transmission and reception but this is
rarely required with modern communications equipment. Ticking the

“Identical Tx/Rx rates” check-box simplifies the dialogue.

A line speed of 115,200 Baud is adequate for the highest sample rates that the

instrument can generate. It may be necessary to reduce the line speed if the
data are to be passed over a modem or wireless link.

The “Stop Bits” drop-down menu should be left at 1 unless your
communications equipment requires a different value.

5.9.5 Data flow

The digitizer operates in one of several transmission modes. These modes

relate to how the unit uses its Flash memory:

•

as a simple data store, from which you can request data (FILING and
DUAL modes);

•

as a buffer holding unacknowledged blocks, which are transmitted in

preference to real-time data (FIFO mode);

•

as a buffer holding unacknowledged blocks, which are transmitted

whenever the transmission is free but no real-time data blocks are
ready (ADAPTIVE mode);

•

not at all (DIRECT mode).