Guralp Systems CMG-DM24S12AMS - Manual (Page 31)

CMG-DM24S12AMS Operator's guide
The baud rate you choose must satisfy two conditions:
•
It must be high enough to allow all the transmission of all data
generated by the digitiser at the sampling rates you have chosen.
For three streams of data at 100 Hz, for example, 9600 baud will
usually be sufficient. If you wish to transmit 200 Hz data,
however, the baud rate must be at least 19200.
•
It must be low enough to fit within the operating range of the
telemetry equipment you are using. While modern modems often
offer transfer rates up to 56 kbaud, the telephone or transmission
lines may not support these rates. The same holds true for radio
telemetry.
Usually, the transmit and receive rates of the data port will be the same.
If not, you may select different data rates by removing the check in the
box marked Identical TX/RX rates.
The Stop Bits option allows you to choose whether the serial link uses 1
or 2 stop bits. In most cases this can be left at 1, although 2 may be
required if you are sending data over ‘difficult’ transmission lines (for
example, some types of radio link.) Using 2 stop bits will add a 10%
overhead to the data.
You will also need to set the data rate for Scream's local Com port, as
well as for the SAM/DCM or other communications device (if you are
using one). In Scream!, you can configure a Com port by right-clicking
on its icon (not that of the digitiser) and selecting Configure... from the
pop-up menu: for more details, consult the online help or user guide for
Scream!. If you are using an additional communications device, you
should consult its documentation to learn how to set its baud rate.
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