jgcode

QUOTE (neBulus @ Feb 21 2009, 12:47 AM)

The Modbus libraries that NI had their web-site where OK if that was all you were doing so they make a nice demo. They did not play well with other process. I went through and refactored them adding "zero ms wiats' to loops and some other stuff.

FWIW, I prefer to use the IO Server when communicating with Modbus on RT rather than those VIs.

QUOTE (george seifert @ Feb 20 2009, 03:26 AM)

It's fixed. Installing NI-DAQmx 8.8 solved it. Which is weird because the installer installed MAX and NI-DAQmx. The installer did a minimal install though so maybe the full install provided something else.

George

I don't usually use the installer to install DAQmx as the size blows out.

The new drivers - DAQmx 8.9 - are just shy of 1.2GB!!

So I normally get the client to install if off the discs supplied by NI.

If the user does a DAQmx install without LabVIEW installed on a PC then by default the option for "support for (e.g. LV8.5)" is not selected.

This can mean supporting VIs are not installed and if you call them in your application then you can get a broken run arrow.

I find the generic error LabVIEW returns to be pain as well, a little bit more info would go a long way to discovering the cause of the broken run error.

If you scroll down about halfway http://zone.ni.com/devzone/cda/tut/p/id/3021' target="_blank">here NI provide info on the differences in the Runtimes for an installer under the heading:

Q: Can I include NI-DAQmx as an additional installer with the stand-alone application I have created in LabVIEW?

[cross posted to ni.com]

Problem:

LabVIEW seems to be overriding a value of 1 to a value of 2 for the Sample Quantity.Sample Per Channel DAQmx Property Node for a Continuous acquisition mode.

Information:

I have a task set up in MAX (version 4.4.0f1).

When I set Samples To Read to 1 the task runs correctly in MAX.

When I read the task in LabVIEW (8.5) the Sample Quantity.Sample Per Channel property node (which is the Samples to Read) is coerced to a value of 2.

If the value is greater or equal to 2 in MAX then the Sample Quantity.Sample Per Channel property node in LabVIEW returns the correct value.

I get the same problem with a real device or a simulated device.

Question:

Is this desired behavior?

Side note:

If N Samples (finite buffer acquisition) is selected Samples To Read cannot be 1 as it causes an error 200077 - it must greater or equal to 2.

But no error occurs when the task is saved as Continuous (continuous buffer acquisition). I don't know if this is related. The error generated is:

Error -200077 occurred at DAQ Assistant

Possible Reason(s):

Measurements: Requested value is not a supported value for this property.

Property: SampQuant.SampPerChan

You Have Requested: 1

Valid Values Begin with: 2

Valid Values End with: 8589934590

Device: cDAQ3

QUOTE (JustinThomas @ Feb 19 2009, 12:58 PM)

Anyone know of a way to add icons to run time menus in LabVIEW?

I proposed that question http://forums.lavag.org/UI-Controls-t11699.html' target="_blank">here - there are some good links in the topic i.e to some of PJM's code.

QUOTE (Nikunj @ Feb 15 2009, 03:26 PM)

Actually i am developing project using labview 8.2 in which i need run time menu. i.e after running the user will choose options from menu for changing some parameters. I see some examples of run time menu but i couldn't understand how to set item tags and item paths for them and dialog box also.

Hi Nikunj

Here is a demo on how to make a start using RTMs in your VI (no audio).

Here are some links to the KB as well:

Help

Shortcut menu but the principle is still the same

Coded in LV8.6; Save For Previous as LV8.0

Download File:post-10325-1234680993.zip

QUOTE (shenghuoshi @ Dec 6 2007, 11:45 PM)

<<labview gui:Essential Techniques(Paperback) >>by David j.Ritte

Goodluck getting a copy - I am waiting for a reprint.

Check the wiki: http://wiki.lavag.org/LabVIEW_Books

QUOTE (WGMres @ Feb 8 2009, 05:09 AM)

When should Tasks be used in a DAQmx application? In the case of sampling channels with similar timing and triggering?

Thanks.

I am thinking the correct answer here would be tasks are used every time.

Resource allocation and scheduling is done in DAQmx using the task state model.

http://zone.ni.com/devzone/cda/tut/p/id/4656#toc2' target="_blank">KB

Hands On Introduction to LabVIEW for Scientist and Engineers (Paperback) by John Essick

I saw this new LabVIEW book on Amazon.

From the Product Description it seems like it is aimed at entry level academics.

Anyone read it or know if its any good as a reference?

Edit: I added this book to the wiki

QUOTE (cheekychops @ Feb 4 2009, 10:40 AM)

Basically I have the following excel sheet, I want to read the first coulmn into one array and the other into another.

jdunham is correct.

Additionally:

The Index Array function is expandable (so you don't need to use two) just pull down on the bottom of it to expand it &

If you explicitly set and index then the next, same index is that value plus one (+1).

I thought this was worth mentioning as it can neaten your code.

http://lavag.org/old_files/monthly_02_2009/post-10325-1233720826.png' target="_blank">

Congrats on passing the CLAD

QUOTE (crelf @ Jan 17 2009, 05:43 AM)

Intermediate 1 and 2 are the key - If you've done and understood those, then you will be fine.

IMHO & from an 8.2 course perspective (in case it has changed), the exam structure is based solely around Intermediate 1.

Intermediate 2 (Connectivity - now & Performance) - although a great course, was not needed when I sat CLD

Unless it has changed you could save some cash by doing just Int 1?

I agree with what has been said already here:

If you are ready experience wise (logged wire time is at appropriate level) then the following will help for the exam:

Do the Int course, understand the course materials

Do the online prep course

Do the exams online &

1) Ensure you complete them with time to spare

2) Make sure the app works - all features in the spec implemented

3) Following a recommended NI layout/architect (coz they will be marking it)

4) Document everything (FP objects, SubVIs, Modules, etc..)

Goodluck

Congrats on passing the CLAD

QUOTE (crelf @ Jan 17 2009, 05:43 AM)

Intermediate 1 and 2 are the key - If you've done and understood those, then you will be fine.

IMHO & from an 8.2 course perspective (in case it has changed), the exam structure is based solely around Intermediate 1.

Intermediate 2 (Connectivity - now & Performance) - although a great course, was not needed when I sat CLD

Unless it has changed you could save some cash by doing just Int 1?

I agree with what has been said already here:

If you are ready experience wise (logged wire time is at appropriate level) then the following will help for the exam:

Do the Int course, understand the course materials

Do the online prep course

Do the exams online &

1) Ensure you complete them with time to spare

2) Make sure the app works - all features in the spec implemented

3) Following a recommended NI layout/architect (coz they will be marking it)

4) Document everything (FP objects, SubVIs, Modules, etc..)

Goodluck

QUOTE (zmarcoz @ Jan 13 2009, 05:33 AM)

I see an MCQ, there are two VIs

one is add 2 number together

one is DAQ vi inside a while loop

which one is simple VI

both of them are simple and general<-- that is what I think

This is terminology on design patterns from NI:

Simple VI - block diagram is usually a component/function - typically a subVI

General VI - block diagram contains parts e.g. initialise routine >> main (loop) >> shutdown routine.

Therefore use the above terminology IMHO:

"add 2 numbers" = simple VI

"DAQ vi inside a while loop" = general VI

QUOTE (Jim Kring @ Jan 13 2009, 10:37 AM)

Oh great. I haven't even started working with Vista seriously and now I need to start thinking about (and avoiding) Windows 7.

I wonder if Vista will just be like Windows ME and we can all just agree to forget about it, eventually.

I think that is the point - MS were suprised at XP's extended lifescycle/the fact that Vista was a dud.

Therefore MS are planning to market Windows 7 at all the people still clinging onto XP and won't upgrade to VISTA.

Essentially bypassing Vista completely.

I think the Vista interface is great, but issues with UAC, driver support, overhead etc..

XP still has its place, it is lightweight and a great candidate for EEE PC's and smaller devices.

Windows 7 feels very much like Vista from the GUI perspective.

Under the hood tho it is going to need to be good to swing a lot of unhappy people.

QUOTE (hooovahh @ Jan 9 2009, 11:23 PM)

I'm sure this is just for playing around but I must say you are very bold to try to develop LabVIEW code in a beta operating system.

Of course it is just for sh :beer: ts and giggles, but it would have been cool if it worked!

My LabVIEW 8.6 installer does not work with Windows 7 Beta

ttt

I have an application whereby I am able to crash the LabVIEW Run Time Engine (8.5).

1. My application consists of a Template VI (which is always in memory) that dynamically loads VIs into a subpanel.

2. These dynamically loaded VIs contain LVOOP classes.

3. In my Build Script in LV AppBuild I rename my LVOOP class VIs with a prefix (I have no inheritance) in order to try and neaten the build.

4. I build the application (success) and run the executable.

Randomly the LV RTE will crash when switching between screens (i.e. unloading then loading a dynamic vi into the subpanel).

Sometimes on the first switch, other times the 50th switch.

Fixes I have found:

1. In the template VI I host an object of each LVOOP Class as a constant of the block diagram. This must keep the class in memory the whole time? As switching between screens in the subpanel is way faster. Seems to be alot of overhead in loading the different classes.

2. Do not rename the LVOOP Class VIs (resulting build structure is more complex) in the build script.

Either solution seems (thus far) to make the Application way more robust.

Of course with inheritance I would be forced to use Fix 2 as with Fix 1 I would have to use the same prefix (which would still cause a name collision etc..).

Question: Is there a known issue with the LV RTE dynamically loading/unloading VIs containing classes that have a prefixed name?

If so is this fixed in 8.6 (I dabble in 8.6 at home from time to time but 99.9% of work is 8.5 or 8.5.1 so) I haven't tried with this app.

There are some great reads on LAVA about related topics here and here

[Cross Post]

QUOTE (zmarcoz @ Jan 3 2009, 10:51 PM)

1.How much will it cost to take the CLD exam?

2.Does CLD exam require you know some special function of Labview? for example, ask you to do rs232 connection with equipment, activeX, using NI-DAQmx, etc

3. Where I can buy the course manuals

4. What book is good for studying CLD exam?

5. Do I know the CLD exam result right away?

6. Any good guide to study the exam?

1. I am in a different country but at the time it was ~ US$200 (discount for NI Alliance member may have applied)

2. No, your objective is constructing a working VI from a given spec [E.g. Traffic Light, Security System, Carwash] and being marked on Functionality, Documentation and Style. It is software development, not hardware so there is no NI-DAQ, Serial and there is no ActiveX.

3. Contact NI Training

4. The manuals are great. You really only need Intermediate I as Intermediate II is about connectivity (VI server, TCP/IP, ActiveX) and whilst great stuff is not critical IMHO. LabVIEW For Everyone is still a great resource for CLD IMHO

5. No, I am under the impression that a certain group of people at NI mark the exams for consistency so there is a turn around cost associated with this (they said 2 weeks in my country, but it was more like 4-5 weeks - but it was around NI Week time so I cut them some slack)

6. [E-Kit] Yes read the course manuals, do the examples, the prep course, read lots (LAVA is great) and practice as time is tight for some (if not all) of the specs

QUOTE (zmarcoz @ Jan 3 2009, 01:57 PM)

I want to learn middle level labview and take the exam. I just graduate and don't have job, so I can't afford to pay $5500. Is there any book that I can buy to study myself? Can I just take the exam instead of buying the whole package? How much will it cost for the exam only? Anyone has the experience please help

Hi Zmarcoz.

Sitting the NI courses (which I am assuming your are talking about by mentioning $5500) is not a prerequisite to taking the NI exams.

However, the course material does lend it self well to the exam content, as the exam assumes you have the knowledge presented in the courses.

If you have the time and enjoy self study you can purchase the course manuals at a substantial price difference to taking the courses.

Although I am a big fan of the NI courses and certification, there are however other good non-NI references out there.

For example, IMHO, LabVIEW For Everyone contains all the relevant information to pass the CLAD and is about 60 bucks.

If you search LAVA you will be able to find other topics on good references as well like this one

Happy New Year...

A little SNL flavor to ring in the new year...

QUOTE (Ton @ Dec 29 2008, 03:45 PM)

Hi Malani,

your question is a bit unclear, but I would have a look at the 'http://zone.ni.com/reference/en-XX/help/371361D-01/lvprop/vi_sve_instrument/' target="_blank">Save Instrument' method.

Ton

You can do it manually as Ton suggested or there is an Open G install by Jim Kring called Rename Folder of VIs that will install into your LabVIEW runtime menu.

QUOTE (crelf @ Dec 25 2008, 05:10 AM)

Can you set "Scale all objects on front panel as the window resizes" dynamically? Here's the static method:

But I don't see see it in the properties list for dynamic control:

Hi crelf, its an invoke node of a pane.

QUOTE (sachsm @ Dec 20 2008, 07:47 AM)

I was thinking of caching the references but this could be dangerous if the PC restarts in which case I suppose

the original references would be invalid. Just wondering if anyone could think of a more clever way to do this to avoid the time penalty of opening the reference.

Thanks

Hi Sachsm

Perhaps you could still cache the references as suggested above but run them through a proxy on each call.

I.e. if the reference is good (no error) use cache (fast);

In that case that the reference is bad (error) then [run state machine] to open a new reference (slow), update cache, then use cache.

Therefore you avoid the time penalty associated with opening a reference each time, but you have the proxy ready to kick in when needed to avoid an error that can be handled from a dead reference e.g. when the PC restarts.

And all this can be relatively transparent.

QUOTE (LV_FPGA_SE @ Dec 9 2008, 03:50 AM)

I wrote that example and application note and would love to hear any feedback.

Well I have used it - and I say damn good job.

I actually integrated it into a license manager (client specification) for a third party device and am looking forward to using the NI Hardware component in an upcoming project.

The application note was really helpgul and easy to follow.

:beer:

God would not need to wear a glove.