Need PDA Recommendation

[Robbob]

The error you put sounds similar to error -200428

Check out This KB and see if it provides some information, especially the part about putting the create task before the createvirtual channel.

Edit - Fixed Link

Message Edited by Robbob on 09-17-2009 03:35 PM

[Bill_Jacobs]

Thanks to everyone who has posted responses to my questions.  I've got a few to respond to all at once.

To Nickerbocker -- you suggested a tablet PC and/or WiFI options.  For this application, I really do need a PDA.  Portability is key here.  An engineer using it will have to hold a sensor or possibly two, data acquistion hardware with a connected battery and be able to walk around controlling when samples are recorded.  The PC component must fit in one hand and the engineer needs to be able to press a button with the same hand to take a sample.  Sometimes this will happen in quite unfriendly environments.  I've considered tablet PCs.  Too big.

I really want to make the PDA option with a USB device work.  This is the best option for me.  If I can't, I think I might have to go to a single-board RIO platform.

To BenBabb - Yes, I have the USB-6009 or the USB-6210 connected to the USB host port.  There aren't many PDAs with host ports and Windows Mobile 5 which was a primary reason for trying the Archer.  Your sales guy sent me an adapter cable so I could plug my devices into the correct port.

To Robbob - As it turns out, I was already calling the Create Task vi before the Create Virtual Channel.vi.  One of the NI tutorial documents or web pages must have done it that way, so I did too.

Let me lay out where I am with this.

I have four separate programs.  I have two versions of each.  One version runs on my development PC which has LabVIEW 2009 and NI-DAQmx BAse 3.3.  They all work perfectly on the development PC.  I have mixed results on the PDA.

Program 1 is called Mobile Tutorial and is basically the demo vi that is created using the Getting Started with the LabVIEW 2009 Mobile Module guide.  This mostly runs fine on the PDA.  It uses simulated data.  Does not need NI-DAWmx Base at all.  The only problem with this is minor.  The axes on the plot do not autoscale properly.  That is not important right now.

Program 2 is called Detect Devices.  I found this in the forums here.  I believe it does use NI-DAQmx base on some level.  It also runs fine on the Archer PDA.  It makes a call to Find Devices.vi which is provided with LabVIEW in vi.lib.  This works and it does correctly identify either my USB-6009 or my USB-6210.

Program 3 is called AI Dynamic.  All it does is attempt to create an empty task (DAQmxBase Create Task.vi), add a channel or two (DAQmxBase Create Channel.vi), then clear the task (DAQmxBase Clear Task).  This VI will run, but it hangs on the call to Create Channel.  A few times, the call did return with a -200220 error, meaning the device identifier was invalid.  If I take out the Create Channel call, the program runs.  It will create an empty task and then clear it.  Not useful, but at least it proves NI-DAQmx Base is installed, I hope.

Program 4 is called AI Static.  I just wanted to see if I could use a static task on my USB-6009.  I can't.  I correctly used the NI-DAQmx Base Task Configuration utility to set up my task.  My AI Static vi starts the task (DAQmxBase Start Task.vi), tries to read a sample (DAQmxBase Read.vi) then stops the task (DAQmxBase Stop Task.vi).  I created this one late last night.  It will not even load on the Archer PDA.  The error message is "The file 'AI Static' cannot be opened.  Either it is not signed with a trusted certificate, or one of its components cannot be found.  You might want to reinstall or restore this file."

Apparently something necessary is not on the PDA.  I found another formu discussion thread

http://forums.ni.com/ni/board/message?board.id=170&message.id=351329&query.id=267990#M351329

that talks about a similar problem.  Unfortunately, the target is running Windows CE, so I am not sure how much of the info applies to me.  In that thread there is mention of a tool called pget.exe that you run on the development system  The argument is the name of a DLL and pget tries to retrieve that DLL from the PDA.  The point is to simply check for existence of the necessary DLLs.  I have all the DLLs listed in the discussion, excdept for COREDLL.DLL.  I have no idea how to find that and get it installed on the Archer, if I even need it.  Like I said, that discussion covered a Windows CE target.  This one is WM5.

Any thoughts?  Ben, you've used the mobile module and a USB-6008 or USB-6009 with the Archer.  There is a PDF on the Juniper Systems website of you doing this.  This combination worked for you?  You collected data?  What versions of LabVIEW and NI-DAQmc Base did you use?

Thanks

Bill

[BenBabb]

Hello Bill,

When I created that app I was using LabVIEW 8.5 with that version of NI Moblie.  I used the version of DAQmx Base that came, I think it was 3.2 but could have been 3.1.  It used static created tasks and it never gave me any trouble.  It isn't shown very well, but I had used a USB-6008 OEM DAQ card in that test fixture.  The data gathered was for our production line to test the dock's we build for the Archers.  That test program is still being used on our production line.

I thought I would create a new mobile app using LabVIEW 2009 andtheMobile Module 2009 with my USB-6009.  I hadn't installed LabVIEW 2009 yet so this is new to me as well.  I to had some difficulties getting the application to work.  I get the following error when I try to execute my code on my Archer PDA.  The next picture is my source code. 

 

On the Create channel vi I just right clicked on the Physical Channels wire and had it create a control.  This control gets populated with all the tasks that were created with the NI-DAQmx Base Task Configuration Utility.  I am not sure if it should do that because those tasks have static constants.  I would have expected something like dev0/ai0 for the Channel Name like regular DAQmx task creation.  I tried running some of the tasks but would always get that error as pictured above.  I tried to edit his box and manually type in Dev1/ai0 and my Archer locked up and would not recover.  I had to do a hard reset to get my Archer back into working order.

I then tried to create the same project from the the article we talked about earlier andthe application just hangs.  In the Physical Channels drop down the text Dev1/ai0 was typed in, but if you select the drop down it auto populates with the tasks from the utility.  The program also does not execute correctly and doesn't throw an error, it just hangs.

I modified the shipping example to show code execution. The code stops at DAQmx Base Create Task.vi call.  From what I can tell there is no time out that fires to throw an error or let you halt the exectuion.  You have to stop task from the Windows Mobile applet.  

I added the indicators to help see what would get executed.  After pressing the run button on the application I would expect to see each of LED's light with normal execution but the first LED does not light.  Is there something not getting set correctly with the DAQmx Base Create Task.vi in my code?  When I read the help on that VI everything but the  new task name and auto cleanup inputs are ignored.  What name should be given to new task name?  I have tried several but nothing seems to work and the examples all have that left unwired.

Anyone have any thoughts?

Cheers,

Ben

[Bill_Jacobs]

Hello Ben,

This is excellent information.  I too noticed that a physical channel control gets populated with the names of static tasks.  I also wondered if that could be correct behavior.

It is good to know that someone else is seeing problems similar to my own.  Your descriptions seem to match my experience perfectly.  I also noticed that the axes on Waveform Graphs do not auto scale correctly.

Since my previous post, I have done two things.  I opened a phone support request with NI.  The engineer is seeing some of the same problems as I am.  Unfortunately, he did not have a USB DAQ device.  He was using a CF-6004.  He was going to try to find a PDA with a host port so he could try the USB devices like you and I have.

Also, I installed LabVIEW 8.6.1 and NI-DAQmx Base 3.2 on a spare computer.   It appears that some of the problems I have with LabVIEW 2009 are not present in 8.6.1, but unfortunately, some are.  With 8.6.1, I seem to be able to do digital IO using dynamic tasks and I can read analog inputs if I use static tasks.  Unfortunately, I'm seem to not be able to do analog input if I use dynamic tasks, which is what I need to do.

In 8.6.1, it appears as if my VI just aborts and I think it is happening when during the call to read the data (step 5 in your last example).

 I'm going to send a link to your post to the engineer who is working on these problems.  I'll keep you posted.

Thanks very much

Bill

[Bill_Jacobs]

Hello again Ben,

Can you try to build and deploy one of the example VIs included with NI-DAQmx Base 3.3 please?  It is named Cont Acq&Graph Voltage-Int Clk.vi.  The NI engineer helping me suggested I try it.

I found that I can run this one on the archer with LabVIEW 2009, using my USB-6009.  However, it is not reliable.  The physical channels control defaults to Dev1/ai0.  If I start and stop the acquisition, and change the physical channels to Dev1/ai0:3 or some other value, and start and stop the acquisition, it will soon lock up.

Thanks,

Bill

[BenBabb]

Well, I am not having much luck with that shipping example either.  I can not get any responce at all, the software just hangs.  I then tried to name the task something, by accident or my predictable naming conventions I named the task the same name a static task was named and I did get an error saying there was a name conflict.  I emptied out all the static created tasks from the utility program and I now recieve this error.

At least this is some kind of progress.

Cheers,

Ben

[BenBabb]

Hello Bill,

I have an update.  The firmware for my USB-6009 was out of date.  This article shows you how to update the firmware on your DAQ device.

I was able to acquire an voltage using the shipping example we were talking about dynamically.

Cheers,

Ben

[Bill_Jacobs]

Hi Ben,

I'm pretty sure my firmware is the correct firmware.  It shows up in the NI-DAQmx Base List Devices application.  And I'm not getting the -200220 error.

For some reason, my screen looks different than yours.  Not sure if that means we are running different examples or not.

The example I have has a start and stop button, so you can start a continuous acquisition and stop it, change paramters and restart it.  If I start and stop the acquisition a few times, it will work for a little while, then lock up on pressing the start button.  It seems to fail sooner if I change the number of channels or the min and max settings.

If you have a little time, could you also try out the digital port examples that use dynamic tasks.  I ran the Write Digital Port.vi example as is and appears to lock up too.  If I wait long enoug, the examples seem to simply abort.

Thanks

Bill Jacobs

[Bill_Jacobs]

I just wanted to update everyone on my LabVIEW 2009 Mobile Module / NI-DAQmx Base / PDA problems.  I worked quite a bit with NI technical support.  They concluded that there are indeed bugs in the 2009 version of the mobile module and possibly with NI-DAQmx Base 3.3.

He helped me find work arounds to enough of the problems that I was able to begin to actually start to develop my application.

[BenBabb]

Hello Bill,

Sorry for not getting back to this post, I was out most of last week due to this wonderful flu going round.

I am curious, what work arounds did they suggest?  Perhaps you could supply some code?

Cheers,

Ben