How to save a VXI configuration

[Justin_E]

Graybeard,

Yes, you can use the NI-VISA API to communicate with your VXI device. There is an article in the NI-VISA help file that compares NI-VISA and NI-VXI functions to communicate with your device (so, if you wanted to, you could also use the NI-VXI API to communicate). To find this document, open the NI-VISA help document. Under the Contents tab, go to NI-VISA Help -> Interface-Specific Information-> VXI -> Comparison Between NI-VISA and NI-VXI APIs.

Try using these VISA functions to talk to your device, and let us know if that works. From here, the next step might be to start reverting drivers and hardware until we can get the card working again.

[Graybeard]

Justin,

I looked at the VISA help file, but I still can't see how to communicate with the DIO-128 using VISA.  For example, I use the DAQ call

    Set_DAQ_Device_Info(dev,ND_DIO128_SET_PORT_THRESHOLD,thrshld)

to set the threshold of the input ports.  This probably writes some value to a configuration register on the DIO-128.  How would I do the same using VISA?  I assume it would be some form of the viSetAttribute function, but I don't see anything relating to threshold in the list of settable attributes in the function description.  I'm having trouble translating the DAQ DIO functions to the equivalent VISA functions.  Thanks.

Regards,
Leo Bostjancic
Midway Research Center/NRL

[Justin_E]

Graybeard,

In double-checking the VISA help file, I did notice that there isn't an easy one-to-one conversion from DAQ functions to VISA commands. Trying to communicate with your device using either the VISA or VXI API is going to require you to look through some of the functions in the VISA and VXI help files and figure out which ones you want to call for which DAQ actions you are trying to perform.

One thing I would like you to try before attempting to communicate using a different API is to step-debug into your DAQ calls to see exactly where this hangup is occurring. This will be useful in letting us know what command or functions are causing this error. 

[Graybeard]

Justin,

The DAQ functions in my CVI program are as follows:

Set_DAQ_Device_Info (1, ND_DIO128_SELECT_INPUT_PORT, port)

Set_DAQ_Device_Info (1, ND_DIO128_SET_PORT_THRESHOLD, thrshld)

Get_DAQ_Device_Info (1, ND_DIO128_GET_PORT_THRESHOLD, &value)

DIG_Out_Prt (1, prt_out, val)

DIG_In_Prt (1,  prt_in, &val)

When I step thru them, they all fail with a status code of -10401, unknown device error.

I deleted the registry key as suggested here: http://ftp.ni.com/support/softlib/vxi/Windows/3.5.2/readme.html#issuesvxidaq

but I see the same error.  I tried setting NI Spy to capture the VISA and VXI calls, but nothing appeared after the initial calls to viOpenDefaultRM and viOpen.

My current configuration is CVI 8.5, VXI 3.5.2, Visa 4.4.1, Trad. NI-DAQ 6.9.3, and MAX 4.5

See the attached MAX report for the full config.

 Leo B

[Eric_K]

Leo,

With the set up that you have now, in which you are receiving these errors, can you still see your DIO-128 correctly in MAX?  Are there any indications there that point to problems with the DIO-128?

Eric K

Application Engineering

National Instruments

[Graybeard]

Eric,

"can you still see your DIO-128 correctly in MAX?"  Yes.  See the attached screen capture.  The DIO-128 appears in the VXI configuration on both MAX panes.  It also appears as a seperate line item in the configuration tree in the leftmost pane.

"Are there any indications there that point to problems with the DIO-128?" Yes.  If I select the DIO-128 entry in the MAX configuration tree, and click Properties, the DIO-128 configuration window appears (attached).  Note the logical address (0) does not match that shown in the VXI configuration (5).  If I select Modify, and change the LA to 5, Windows crashes and reboots when I click OK.  

I know I said in an earlier post that replacing the DIO-128 was not an option, but it now seems clear that is my only option.  We (my boss & I) are reluctant to spend any more time on this, and are looking at alternative devices - probably GPIB or Ethernet based.  Hopefully, the transition to a new interface won't be too painful.  Thanks for your help.

 Regards,
Leo Bostjancic
Midway Research Center/NRL

[Eric_K]

Graybeard,

I understand not looking forward to having to make changes, but for a replacement for you DIO-128 I would direct you to www.ni.com/daq.  There you will find that we offer differing DIO cards for Ethernet, USB, and wireless connections.

Eric K

Applications Engineering

National Instruments