Guralp Systems Limited
MAN-SWA-0011 - Scream! AVD User Guide

Chapter 7. Integration with Scream

While many different configurations are possible, the recommended set-up is to use Scream! AVD as a coprocessor for Scream!, where selected streams are read from Scream!, processed and then fed back into Scream!. It is also possible to use the software as a front-end processor for Scream!, where all incoming data are processed by Scream! AVD before reaching Scream!. This chapter describes both of these scenarios.

7.1 Scream! AVD as a co-processor

In the recommended mode, Scream! is responsible for collecting all incoming data. The incoming streams are pushed by Scream! to Scream! AVD for processing and the calculated streams are pushed back to Scream!, using the network loop-back adaptor.

Note: Because Scream! AVD can only collect data from UDP sources, co-processor mode must be chosen if any data source uses TCP. For example, wireless-attached CMG-6TDs use BRP over TCP to send GCF data, so co-processor mode must be used when working with these instruments.

To configure Scream! AVD as a co-processor for Scream!, first configure Scream! to collect all of the required data. For more information about this, please refer to the Scream! Manual, MAN-SWA-0001.

Once the data streams have appeared in Scream!, open Scream!'s Network control window and select the My Server tab. Tick one or both of the check-boxes Transmit data from local Com ports and Transmit data from Network so that the required data can be retransmitted to Scream! AVD.

Right-click in the “Clients” area of the My Server tab and select Add… from the context menu. Enter the IP address or DNS name of the computer running Scream! AVD – as it is on the same machine as Scream!, you can use the loop-back address, which is 127.0.0.1 – and the port on which Scream! AVD will be listening, as specified in the Rx port field of Scream! AVD's Network settings tab, separating the two with a colon (':').

Once data are arriving in Scream! AVD, select them and map the stream-names as desired, as described in section 5.4 on page 10.

Note: Do not enable the pass-through ('P') streams as they will already be appearing in Scream!, direct from the data sources.

Revisit Scream!'s Network control window and select the My Client tab. Ensure that the Receive UDP Data check-box is ticked, as shown below:

Lastly, revisit the Network settings window in Scream! AVD and set the Scream Port to match the Port used for all network communications at the bottom of Scream!'s Network Control window, as shown below:

Double-check that the port numbers highlighted in red correspond as shown.

Note: The two port numbers, Rx port and Scream port must differ from each other but, other than that, any suitable port numbers can be chosen. The ports chosen must not be

For more information about Scream's Network Control window, please refer to the Scream! Manual, MAN-SWA-0001.

Note: The streams generated by Scream! AVD will be re-transmitted back from Scream! to Scream! AVD, so they will appear in the left-hand instrument list in the main window. Do Not select these streams for processing: this will cause a data loop.

In summary:

7.2 Scream! AVD as a front-end processor

Note: Because Scream! AVD can only collect data from UDP sources, front-end processor mode can not be used if any data source uses TCP. For example, wireless-attached CMG-6TDs use BRP over TCP to send GCF data, so co-processor mode must be used instead when working with these instruments.

To configure Scream! AVD as a front-end pre-processor for Scream!, first configure Scream! AVD to collect all of the required data. The data can be pulled from the source or pushed by the source.

Where data should be pulled from the source into Scream! AVD, configure each data source in the Network settings window by entering the IP address or DNS name, followed by a colon (':') and the required UDP port number. In the screen-shot below, Scream! AVD will pull data from the server at address 192.168.84.100 on UDP port 2008 and from the server with the DNS name banff on UDP port 8050.

Where source systems will push data into Scream! AVD, they should be configured with the IP address or DNS name of the PC and the port specified in the Rx port field. Any suitable UDP port can be chosen and specified for this purpose. In the previous screen-shot, port 15671 is specified.

Once data are arriving in Scream! AVD and the stream-names can be mapped as desired, as described in section 5.4 on page 10.

Note: The streams generated by Scream! AVD will be re-transmitted back to Scream! with a new System ID which will not match that of the original data stream or that contained in the InfoBlock. This means that any existing calvals.txt file will need modification before it can be used and the InfoBlock mechanism will not work for automatically populating calvals.txt.

For more information about InfoBlocks, please see www.guralp.com/howtos/using-infoblocks-with-scream.shtml

Next, set the Scream Port to match the Port used for all network communications, as shown at the bottom of Scream!'s Network Control window, and ensure that the Receive UDP Data check-box on the My Client tab of Scream!'s Network Control window is ticked, as shown below:

For more information about Scream configuration, please refer to the Scream! Manual, MAN-SWA-0001.

In summary:

7.3 Processing recorded data

Recorded data replayed through Scream are not normally transmitted over the network. To enable transmission of recorded data, start Scream with the option

-txfiles

on the command line. This can be most easily done by modifying the windows short-cut or linux start-up script used to launch Scream. For more information, please see this article.