LabVIEW Datalogging and Supervisory Control Module FAQ

How do I upgrade my current LabVIEW 7.1 DSC program to LabVIEW 8.x DSC?

There are three parts to upgrading:

• Import the configuration file - DSC is now variable-based instead of tag-based. You must import all your previously configured tags into the shared variable format. There is an import wizard located in the Tools»DSC Module»Migrate»Configuration(*.scf). One caveat is that if the tags in your *.scf file were connected to I/O servers (OPC, Modbus, and so on), and they are not available, the variables imported will not be bound to the source and will have to be reconnected.
• Remove obsolete code - Some code may be invalid, such as Launch Engine.vi. You must remove invalid VIs to run the VI.
• Adjust/remove HMI Wizard code - Almost all code generated by the HMI Wizard is still valid (except for some Engine and Security VIs), but HMI Wizard created a lot of while loops to change colors and so on. With LabVIEW 8 DSC, you can capture events from variables, so migrating to an event-based architecture improves the performance of the code.

When I opened my LabVIEW 7.1 DSC in LabVIEW 8.x DSC, why do I get a broken arrow?

There are some features that are no longer supported in LabVIEW 8.x DSC, such as Launch Engine.vi. You must remove/replace these VIs to be able to run in LabVIEW 8.x DSC.

Can I run my current (LabVIEW 7.x DSC) process on the same computer as a new LabVIEW 8 DSC process?

Yes. You can run your older processes under the old tag engine simultaneously with the new processes under new the new tag engine.

Can I capture events from the database (alarms, data change, and so on) from an event structure?

Yes. You can now capture events from the database directly into the event structure.

Do I still need a run-time license for LabVIEW 8 DSC?

Yes. The licensing has not changed.

What industrial connectivity options does LabVIEW 8 DSC include?

In addition to the core connectivity option that LabVIEW provides, LabVIEW 8 DSC includes two I/O servers - Modbus and OPC Client. If your device is not Modbus or OPC-compliant, you must first create a VI that communicates with your hardware, then use the new Custom I/O Server Wizard to build a custom I/O server. With any of the three types of I/O servers, you can connect to virtually any type of hardware. In addition, FieldPoint and NI-DAQmx have their own OPC servers.

Can I build and distribute applications with the LabVIEW DSC Module?

Yes. You can use the LabVIEW Application Builder to build your application, including custom I/O servers, into distributable executables. You need a DSC Run-Time license for each computer on which you run the executable version of your application.

What is PSP and did it replace the Logos real-time and historical protocols?

No. With LabVIEW 8, the shared variable engine was introduced to allow for network connectivity and buffered data transfer. LabVIEW 8 DSC uses this engine by replacing its own tag engine with the shared variable engine. LabVIEW 8 DSC is also a plug-in module to the shared variable engine to provide features such as alarming and logging. The shared variable engine uses an enhanced version of the Logos and DataSocket protocols, which allows server-client buffering and RT FIFO architectures for communicating with LabVIEW Real-Time targets. This new protocol, the publish-subscribe protocol (PSP), is a superset of features in DataSocket and Logos. However, Logos (installed via LabVIEW DSC) acts like a plug-in to the shared variable engine by adding the historical protocols (in other words, database and logging features) to the shared variable engine.

Do I need to change my connections from logos:// to PSP on my front panel connections or to my DataSocket VIs?

No. Using the primitive DataSocket VIs and the logos:// protocol descriptor in the URL is still a valid way of connecting to the shared variable engine.

What happened to the Tag Configuration Editor (TCE)?

The tag engine has been completely redesigned and has a new architecture. It is no longer necessary to keep tags stored in the *.scf and configure the entire tag engine by loading this file. All server tags are configured as variables in "libraries." Also, with a new wizard called the Multiple Variable Editor, you can configure large numbers of shared variables for logging, security, scaling, alarming, and I/O server connection options similar to the TCE. Also, you can deploy and undeploy each library with its associated variables independent of other libraries that are currently deployed on the same machine.

How do I launch the "engine" or start a process now?

Launching the tag engine is no longer necessary. The shared variable engine, which replaced the tag engine, "launches" automatically in the background whenever a connection to a shared variable is created or a library containing variables is deployed and running on the machine.

How do I transfer the data in my database to use with LabVIEW 8 DSC?

The Citadel database used in LabVIEW 8 DSC is the same as LabVIEW 7.1 DSC and is fully compatible. You just need to point the new process to the same data directory.

How do I transfer my *.scf files?

There is a migrate utility to change tags to variables. Access this through the menu by Tools»DSC Module»Migrate»Configuration (*.scf).

What happened to custom VI-based servers?

With the new LabVIEW DSC engine architecture, the VI-based architecture is obsolete. LabVIEW DSC now implements I/O servers through the creation of custom I/O servers, which are much easier to create than VI-based servers.

What is the difference between a "deployed" library and a "running" process?

A "deployed" library is configured in the shared variable engine whereas a "running" process has both been configured in the engine and is running. You can stop a process from running, but you can still configure it in the shared variable engine.

What happened to memory tags?

The concept of memory tags has been incorporated into shared variables in LabVIEW 8. In fact, shared variables are essentially tags that are either bound to a source (I/O tags) or unbounded (memory tags).

In the Tag Configuration Editor, where are the equivalent options for the previous Configure»Historical?

You can access historical options through the Library property window by right-clicking on the Library in the Project Explorer window and selecting Properties.

One property in the Configure»Historical is the "maximum time between logs" option, but now I cannot find it. Where did it go?

This option is obsolete and no longer needed. The older engine required this because the historical trends would not update if the data values did not change. Now the engine correctly updates all graphs even when data is not changing. This also decreases the redundant data from being logged to the database, reducing its total size.

In the Tag Configuration Editor, where are the equivalent options for the previous Configure»Events?

You can access event options through the Library property window. In your project, right-click and select Properties. You also can configure alarm strings for each shared variable.

In the Tag Configuration Editor, where are the equivalent options for the previous Configure»Engine?

Buffer sizes are now settable on each variable. Other options such as input queue size, error message repeat rate, and event history buffer are obsolete and no longer needed because of the change in the engine architecture.

Do I have to stop the engine to add or remove tags?

No. Tags are now created as shared variables under Libraries. You can deploy multiple libraries as processes (in other words, running) at the same time. Likewise, you can stop one process (in other words, deployed library), make changes such as adding another variable, and redeploy the library without affecting the other deployed libraries or stopping the shared variable engine. Any logging or events still occur as long as that library is configured properly and deployed.

Did the database change since LabVIEW 7.1 DSC?

No.

How do I implement security now?

Security in LabVIEW 8 DSC is now networked security. It is no longer necessary to distribute your lookout.sec. You must first create a local domain in the Tools»Security»Domain Account Manager. Once a domain is created, you can then create users and configure security.

How do I import my users that I created in LabVIEW 7.x DSC?

Go to Tools»Security»Domain Account Manager. On the My Computer icon, right-click and select Import Lookout 4.x Security.

I have a large VI with a lot of security settings on the front panel. Will I lose all of the security settings?

No. There is a migrate utility for front panel security in the menu option Tools»DSC Module»Migrate»Front Panel Security.

HMI Wizard

What happened to the HMI Wizard?

All features (except color based on alarm condition and scales for the control/indicator) previously edited through the HMI Wizard are contained in the Properties window (right-click on Control/Indicator). You no longer have to create code on the block diagram for changing these properties.

How do I change scales for an object to match the connected tag?

This must be done manually. However, with LabVIEW 8, you can build your own custom controls called XControls that allow the same functionality.

How do I change the color based on the alarm level?

The HMI Wizard accomplished this by generating code on the block diagram. For upgrading processes, this code can be left intact. However, any edits or changes do not automatically update the code. Because the HMI Wizard used while loops in a polling-type architecture, it is better to change the code to event-based and programmatically change the color.

How do I set an indicator to blink based on the alarm level?

This is settable through the Properties window of the shared variable.