Continued Problems with DSC from 7.1->8.2: Can't call memory variables and conversion of src has error

[tug]

The variables from DaqOpc (NI-DAQ) look fine in Server Explorer. I have loaded the latest NI-DAQ, but there is not an option to bind to that server under variable properties. If I bring them up in the VI from DAQ-MX, they are several orders of magnitude off and negative.

[Brinoceros]

Did you try running the executable I mentioned in my last post?  Also, what is the "VI from DAQmx"?  Is this a VI you have created with variables or front panel objects bound to the DAQmx tags you found under System?  Try creating a VI from scratch, placing a numeric indicator on the front panel, then going to the properties and binding it to one of these tags.  I want to be sure we are bound to the correct objects.

[tug]

1) When trying to run C:\Program Files\National Instruments\NI-DAQ\OPC , an error window comes up saying the application failed to initialize.

2) Adding a numeric from the front panel of a new VI, then going to properties to bind provides network objects under the path: "PC Name"\Labview\, provides access to all DAQ-MX tags. Binding to one of these tags can be done, but running the VI provides no data.

[DanRichards]

Hi tug,

Brian is out of the office so I'll be picking up where he left off.

I have attached a simple VI that I'd like you to try running on your machine. Simply go to the properties of the Numeric control and bind it to a tag, then run it. Please let me know if you see data updating. Notice the while loop with the delay on the block diagram. Also, if you have a minute, I would appreciate a recap of the situation as you now understand it. That might help both of us.

Thanks,

Dan Richards

[tug]

Hi Dan-

As a recap, I was previously at Labview 7.1 on this computer. When I did a full reinstall of the operating system, I loaded Labview 8.2. A project file was created and all of my VIs from 7.1 were made part of this project. The original taglist file was migrated using the DSC menu option and used to provide the shared variable listing used in the project, and all were set to auto-connect. I also added an OPC server, which was the "Variable Engine 1"; note that this is the only option, and DaqOpc is not listed, nor is "Variable Engine".

I have both the traditional DAQ and DAQmx software loaded. If I look at OPC servers within the Server Explorer, I have DaqOpc, LookoutOPCServer, OPCDemo, and Variable Engine. Before I loaded the latest NI-DAQmx 8.8 software, I would also see Variable Engine 1 in this view. Note that using MAX I can get good quality results from traditional DAQ for all items, for example 70 DEG F for a temperature input on a 6023E; however, I do not get good quality results for DAQmx, which gives -403.65. Note that although I can get values for DaqOpc in the server explorer, I cannot access these tags for binding--even if I add the Wizard group showing these tags.

Currently for testing your VI, the DaqOpc, LookoutOPCServer and Variable Engine are all running. Wizard groups are loaded with the default items for alarms and points. When I bind to DAQmx network items, which show up under the node address of the PC, I get a value of -403.65--just like that seen in MAX.

As I had been successfully using the DSC module and tags (it worked nicely), I figured using shared variables would be the same.

Thanks,

Craig

[DanRichards]

Hi Tug,

I was hoping to get you an answer over the weekend, but I haven't figured this out yet. Brian might be back this week and perhaps we can team up to get this resolved.

Regards,

Dan R

Applications Engineering

National Instruments

[DanRichards]

Hi Tug,

Considering that the value you see in Max is the same value you see when you watch the tag, I believe your problem is probably in the set up of your hardware. What is the hardware and how do you have it set up? Are you able to see good data in test panels?

Thanks

[tug]

Dan-

I don't think it is the hardware. The DaqOpc server gives fine results in MAX. Only DAQmx does not. The PCI-6023E and 6704. My problem is that I can not access the DaqOpc server to bind to a tag from a VI. Can you say why? If you look at previous posts, you will see I have tried everything suggested in this regard. I even reinstalled the software. The whole system worked excellent under Labview version 7.1.

Thanks,

Craig

[DanRichards]

Hi tug,

How about connecting to OPC servers with Datasockets?

http://digital.ni.com/public.nsf/allkb/F92C1F2F7B35105B86256DB200628B24 

[tug]

I had to change to datasocket for outputs when I switched from labview 7.1, a version that worked great. I would appreciate a resolution on this issue, if at all possible. I only work at the university once per week, but I need to wrap this up and move the lab and this problem has existed since August.

Thanks.