Guralp Systems CMG-DCM build <10,000 - Manual (Page 263)

Acquisition Modules and Platinum Firmware Appendices
4. You will then be prompted to enter COM port and modem details:
The Country/region, Area code and Phone number fields can be ignored: they are
only used when working with modem connections. Select the name of the correct
COM port from the Connect using drop-down menu, then click
.
5. Enter the port configuration settings:
Ensure the following parameters are set:
MAN-EAM-0003 263 Issue E - February 2014