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In what has to be the most off-topic LAVA/OpenG BBQ door prize ever, I'll be giving away two advance copies of my graphical novel Rune: A Tale of Wizards and Kings, which is coming out in October.

--- UPDATE 2012-08-05: Ticket pre-sales are now closed. If you need to buy a ticket at NIWeek, this post has what you need to know. --- It's that time of year again! Are you coming to NIWeek 2012? Do you want to enjoy cold beers and hot mesquite BBQ with your friends from LAVA, OpenG, and the whole LabVIEW Community? Then come to the 2012 LAVA / OpenG NIWeek Bar-B-Q! Year after year we bring together all your best online (and real-life!) friends from LAVA (LabVIEW Advanced Virtual Architects), OpenG (home of LabVIEW's open source community), and even the leaders in NI LabVIEW R&D. Come enjoy great barbecue with great people away from the hustle & bustle of the convention floor. Menu*: Mesquite BBQ beef brisket, chicken, and pork ribs. Potato salad, pinto beans, and coleslaw, and iced tea. There'll be a cash bar, and they have a great selection of brews. Date: Tuesday, August 7th, 2012, 7:00 PM (after the NIWeek "Block Diagram Party") Location: Scholz Garten, 1607 San Jacinto Blvd, Austin, TX 78701 Cost: $30 per person How to buy a ticket: Ticket pre-sales closed. See here to buy a ticket at the conference. *Vegetarian food is available on request -- PM Justin here for info. What to Wear: A LAVA T-Shirt, of course! Door Prizes Galore: Everyone is in the running for one of there super door prizes donated by other LAVA members. (You're welcome to offer up a prize too - hint, hint!)

Hi all, Here at my university, someone asked me for advice on how to build a process control VI for a scientific experiment. What he described seemed like a stereotypical LabVIEW application: the computer has to control a couple of pumps and switches, and apply some basic PID control to keep, for example, the pH (acidity) of a solution constant. All was well, until he added that this experiment has to run for at least a year; any interruption of a few seconds in the process control would mess up the experiment. Oops. So, it seems this should be a high-reliability LabVIEW application — something on a scale with which I don't have any experience. So I'd like to ask you for some advice: how to handle this? Any experiences you'd like to share? A few things that seem obvious: disconnect the controlling PCs from the network; disable Windows Updates (but that follows from the previous point, really); have two PCs, and implement some sort of failover mechanism (but how?); get a UPS, or maybe even a backup generator; test extensively, by simulating all sorts of failure scenarios (any tips here?); extensive logging and monitoring. [*]Anything else? [*]Do you know about any good whitepapers or examples? (I have tried Googling around, but haven't been able to come up with much useful information). [*]Or should we ditch the idea of building this ourselves, and get some professionals to look at it? Any pointers would be very welcome; thanks a lot in advance! Best, Onno

You can still use a Get method. Just you have to make it a singleton (which is the default for a VI, but you have to program it for classes-e.g use a DVR).

I strongly suggest you get a dedicated controller for the mission-critical tasks (think cFP or cRIO) and handle the non-mission critical tasks on the PC (like displaying data, logging to a database or wherever. This means that if the PC goes offline for some reason, the controller continues humming away at what it does best: determinisitc control. Then, you only really need to worry about infrastrucute support (eg: UPS) for the controller - it can continue to control and save data locally while the other system is offline. Also, if you go to the PC to get data off it (I don't expect you're going to run the system completely untouched for a year, right? Not even look at any of the data), doing so won't interupt the process. This is a common option in mission critical systems: we built a similar system a few years ago with 3 parallel controllers (PXI) that could take over from each other within 1ms of a detected failure (those specs are probably overkill for your application, but the technology remains the same). We achevied this using reflected memory (a PXI card with a fiber optic link between them, that all "shared" the same memory) - this worked really well. Another option is to stream reflective memory over a local LAN dedicated to the controllers. I've never been to Amsterdam... The answer to that question depends on just how important that determinism is. If you trust your engineers to make something that won't fail, then maybe do it alone. That said, if they misplace one bit, and the whole thing comes crashing down in the last month of the experiment, you might be cranky An even worse scenario (which I've seem many times) is when it *looks* like everything worked fine, but there's an offset or skew in your data that you don't find out about until you've published - *that* would be a nightmare!

From the 2012 home of the Olympics National Instruments UK will be donating an official Olympic polo shirt as a prize Looking forward to seeing y'all (Got to practice my Texan)

Jonah Paul (Product Manager for LabVIEW RT/FPGA) is very excited to be attending the BBQ and giving away a brand new LabVIEW RIO Evaluation Kit! HW geeks - tell me you're not drooling - I am

Cool. Cool Cool Cool.

And on behalf of the NI RF Team, once again I'll be offering up a flight around Austin, time weather and schedules permitting. You will get the chance to view our beloved Austin from the air and take the controls of N2817F, a High Performance Cessna Skylane 182. Any training on aviation, RF or PXI along the way is an extra kicker out of the kindness of my own heart.

Poly VI with CRC8, CRC16-CCITT (0x000, 0x1D0F, 0xFFFF), CRC-IBM, CRC32 Some reading material: http://en.wikipedia.org/wiki/Cyclic_redundancy_check http://www.pvlteam.com/doc/crc/algos.htm http://www.miscel.dk/MiscEl/CRCcalculations.html http://web.archive.org/web/20071221025748/http://www.joegeluso.com/software/articles/ccitt.htm crc.zip

Here's an existing colleciton of CRC functions: http://forums.ni.com/t5/LabVIEW/Checksum-calculation/td-p/86249