Guralp Systems CMG-DCM User Manual

Page 36

CMG-DCM Data Communications Module

Real-time data transmission

You can use the

DATA OUT port (or any of the DCM's serial ports) in

several ways, depending on the

service you have chosen to run on the

port.

•

By default, the

DATA OUT port runs the getty service, which

allows you to connect to the DCM's console.

•

The

mgetty and mgetty_raw services are similar, but can deal

with connections made through modems.

•

The

gcf_out service causes the DCM to combine the incoming

GCF streams and send them on transparently, as for a Güralp

SAM or CRM.

•

The

gcf_in service turns the port into an extra digital data input

port. The DCM's

PORT A and PORT B run the gcf_in service.

To change the service running on a port, click the

Configure – Port link

in the serial port table, and set the

serial.x.service option to the

required value. Alternatively, issue the command

gcfgdbset serial.x.service service

Scream! server

In a straightforward vault installation, we recommend that you leave

the

DATA OUT port running the getty service for emergency console

access, and instruct the DCM to act as a server for incoming data on

your network. This can be done from the Data transfer – Scream
server page on the Web site:

1. Enable the Scream! server on the DCM by setting

datatransfer.scream.server

and

datatransfer.scream.server.allowserialaccess to yes. Make a note

of the port number

datatransfer.scream.server.port, or change it

to another. Click Save settings.

2. Start up Scream!, and select Windows – Network Control...

from the main menu. Switch to the

My Client tab.

3. If it is not already selected, check Receive Data to start Scream!

listening.

4. Right-click anywhere in the Servers list box, and select Add

UDP Server.... Enter the IP address and port number of the

Issue F