ALARM Meeting Recaps

[Dave_Thomson]

This thread has been started as a repository for brief recaps of ALARM meetings.  ALARM organizers will post a recap here for each meeting as a reply to this thread.  Please start other threads for any additional discussion of the meetings or other issues.

December 11, 2008 ALARM meeting, CU Boulder

    We had a great turn-out at our meeting last night, with over two dozen people showing up.  Thanks to Laurel for arranging for the room and to NI for the pizza and drinks!  Phil Gold and Joe Des Rosier demonstrated some powerful and flexible RF hardware and software.  Laurel Watts presented an ozone measuring instrument powered by cRIO, and Mark Stangl demonstrated the Vision Builder toolkit.

    Our next meeting is scheduled for March 19, 2009 at the Colorado School of Mines.  Possible topics include various ways to read and write configuration files, a UI demonstration involving nested control panels, and an in-depth look at Shared Variables.

[Dave_Thomson]

March 19, 2009 meeting, CSM, Golden

    In my opinion, this may have been the best ALARM meeting yet.  The turnout was great (about 30 people) as were the presentations.  Many thanks to NI for the pizza and for the web conference with several NI engineers.

    Asa Kirby, Arun Veeramani, Darin Gillis, and  Devin Koopmans gave a great presentation on the ins and outs of Shared Variables.  Many features, caveates, tips, and behind-the-scenes explanations were provided.  This discussion will continue in another thread here on the ALARM site, a document of questions about Shared Variables, and quite likely another conference call with Asa, the other NI engineers, and interested ALARM members.

    After the Shared Variables presentation, a number of people presented their personal favorite techniques for saving configuration information.  Bill Van Arsdale presented a tool he created that parses clusters to automatically create the key names and write and read the configuration parameters to files.  His solution included an additional feature for handling comments in ini files, which is something oddly missing from the standard implementations.  Bill also described the limitations of configuration files, particularly the performance issues seen when the number of parameters grows large.  In addition, Bill presented a tool he created for making RTF documentation.

    Dave Thomson presented two methods of saving configuration information.  One tool is built off of NI's config file VI's and addresses some of the common issues with using these VIs, preventing mis-namings and implementing a way of supplying default values for keys that aren't present in a file being read.  The second method Dave showed is a tool developed by David Moore called Read Write Anything.  This is a free tool that is worth WAY more than you pay for it.  Moore wrote this from the ground up, so it doesn't use the NI config file VIs, and hence doesn't suffer from their performance issues.  Speed when reading and writing large data sets is impressive, and Moore has benchmarks available comparing this to other file types.

   Mark Stangl then showed a simple but effective configuration writing method that uses a property node to get or write the values of all the controls on a front panel.  This method is very simple to program and creates a not-human-readable file, which can be an advantage in some situations.

   Erik Arentzen then presented a clever user interface example in which a main control program populated three sub-panels with dynamically instantiated VIs.  The VI's could then be un-docked, so that they were removed from the sub-panels and became floating windows.  They could also be re-docked.  The flexibility this provided for the user interface is impressive.

   Our next meeting is May 21 at CU in Boulder.  Presentations are needed.  Feel free to contact us if you have something to present.

[cirrusio]

Dave,

Is Bill planning on putting up his tool that he  demonstrated for documenting projects, etc.?  Just curious.

Matt

[mikema111]

I'm sorry I haven't made ALARM meetings for quite some time, but I'd like to comment on the speed issue with the LabVIEW .ini handler.  If you research it you'll likely find the problem lies in the Read Key (String).vi, more specifically down in the Parse Stored String.vi-->Get Next Character.vi.  This seems to now be password protected, but back in I believe 8.2 it wasn't and they introduced the ability to handle multi-byte characters with this particular vi.  It turned out to be an order of magnitude slower than without this capability in the previous LabVIEW version.  I use .ini's to store large arrays in the form of strings, and my boot time on the code went from under a second to 30 seconds due to this change.  I worked around the issue by creating my own version of this vi and its call strings.  Unfortunately, I can not post the code here due to proprietary issues, but I'll say that the fix is to not worry about multi-byte characters.  To be honest I don't know what their value would be.

It may be worth investigating if this is where your speed issue lies with .ini's.  A quick fix could make your .ini handler much more valueable.  I've used a very similar method for storing control values for a while and it's the way to go!

Mike Matthes

[Dave_Thomson]

   We had some interest after the last ALARM meeting in a follow-up discussion with the NI engineers on Shared Variables issues.  If anyone wants to participate in this discussion, please add comments, questions, and issues to the Shared Variables Issues document that is in the Documents section of the ALARM website.

DaveT

[Dave_Thomson]

   The May 21st meeting of ALARM went well, with a turn-out of around one-and-a-half dozen people.  NI provided pizza.  (Thanks again, NI!).  I presented a tool for acquiring streaming serial data that uses a configuration-based approach, allowing a system to acquire data from different sources with little or no programming.  This tool (OSDS) is available on my website.  Laurel Watts presented a follow-up to our previous discussion of configuration tools.  Her example stored the configuration information in a binary format, specifically to prevent unauthorized editing with a text editor.  She plans on posting an example template on this website soon.  Bill Brown presented a small part of a rather large application in use at Ball.  It is a very impressive test executive framework that allows control of a wide range of hardware and software over the network.

   We are gathering ideas for future presentations.  Please contact us if you would like to present at an upcoming meeting.

   See you on September 17th in Golden.

DaveT

[wevanarsdale]

"... We are gathering ideas for future presentations.  Please contact us if you would like to present at an upcoming meeting.  See you on September 17th in Golden."

Dave:  I have a speech recognition demo if there is any interest... Bill

[Dave_Thomson]

Bill,

   What is the nature of the demo?  The reason I ask is that Will suggested that he or someone else might demo a speech recognition tool that Norm K. developed.  If it is the same demo, perhaps you could talk to Will about who might present it.

Dave

[wevanarsdale]

Dave:  I'm developing examples based on LabVIEW 8.6 sample code at http://decibel.ni.com/content/docs/DOC-4477.  I'm using voice commands in a producer-consumer architecture.  I may try to come up with an Insteon demo for commanding electrical devices using voice commands.  However, I don't know if such a demo would be portable.  Bill

[Dave_Thomson]

Well over two dozen people attended the September 2009 ALARM meeting.  It was good to see a lot of familiar faces as well as quite a few new ones.  Thanks to NI for the pizza!

Nancy Hollenback gave a great presentation on getting going with LVOOP.  Hopefully some more ALARM members will be trying out this technology before long.  Joe de Rosier made a presentation on scripting, including an impressive demonstration of the LabVIEW Speak tool.  (It was suggested that Nancy could get LV Speak to recognizer her voice better if she took up smoking.  We hope to hear back on how that works out.)  Trevor Christman from inside NI was available by phone to answer questions on scripting.  We ran out of time before Bill Van Arsdale could give his presentation.  Stay tuned next time...

Thanks to everyone who presented.  Check back at the ALARM site soon for a poll about possible topics for the next meeting.

DaveT