How do you read temperature from a thermocouple using NI-DAQmx and Visual Basic?

[papaya]

Hi Jordan D

Seems We are going around and around away the Express way, how can we shift back the right way? early reqired me to install daq693, now switch to daq741? To down one copy daq741 from NI needs 6 hours,so terrible.

Would you make sure that I must down one copy daq741 to drive ni4351? Or the daq744 can drive it too?

and where can I find the daq744 or daq741 maunal function reference? search Ni website, only daq7.x function reference. all the same?

I have these copys:daq693.daq742,daq744,ni-435x driver 2.5,ni-435x driver 2.5.1.daqmx8.3.daqmx8.5 and measurement studio 8.0 for vb.net 2005.labview 8.2 full development version, labview/cvi 8.1.

How to drive the NI-4351?Anyway, Thanks for your help and patience.

Best Regards!

papaya

[Jordan_D]

Hi Papaya,

I have looked into this issue and have a few resources that I would like to point you to.

First, you are correct that the Traditional DAQ 7.4.4 driver release notes do not specifically indicate that it supports the 4351. I have tried running a 4351 on a computer with this driver and everything worked fine. That being said, the Traditional DAQ 7.4.1 driver is the most updated Traditional DAQ driver that DOES specifically mention support for the 4351.

Some things to keep in mind:

You cannot have DAQmx installed on a computer with an NI-DAQ driver version 6.9.x (or lower).

Does your card work in the MAX test panels? Does it work in LabVIEW? If so have you looked at all of the documents linked below?

Where to Start with Your NI 4350/4351 (Page 4)

Start » Programs » National Instruments » Documentation » NI-435x C & VB Help

C:\VXIpnp\WinNT\ni435x\examples\VB

[papaya]

Hi Jordan D

Read the documents early, and install daq744 ni435x driver 251. the 4351 was tested by max ok. and I try run the example vb60,measure RTD with accesory ok.

can we continue to try the method using vb.net DLLimport function to drive ni4351 unber vb.net 2005? as you sugguest early.

<DllImport("nidaq32..dll")> _
Public Shared Function Acquire(ByVal instr As String, ByVal outstr As System.Text.StringBuilder, ByVal outstrmax As Integer) As Integer

End Function

Best Regards!

papaya

[Jordan_D]

Hi Papaya,

What happens when you try to import the functions from the ni435x.lib?

[papaya]

Hi Jordan D

The problem is how to pass parameter to ni435x_init(VIrSRC resourcename,VIboolean IDQuery,VIBoolean resetDivice,VISession *DAQSession) which requires the VIsession *DAQsession? where the difination of VIsession DAQsession?

vb.net byval or byref?

try this function call as (checkerror=ni435x_init("device1::2",true,true,"VI")),then get an error show me(cannot get return value).

papaya

[Jordan_D]

Hi Papaya,

After searching through my resources I have been unable to find much information regarding the use of VB .NET with the 435x driver. I found the following discussion forum which might prove valuable to you but since VB .NET is not supported for this driver, and we have very little resources (many of which I have already sent you) I am limited in my ability to help you through this problem.

Driver version for NI4351 under XP

The "VISession *DAQSession" variable that you are referring to in your post is a pointer to an empty VISession that you need to declare earlier in your program. Unfortunately this is all the help that I am able to provide on this issue.

[papaya]

Hi Jordan D

Thanks for your help here and my users decide  not to use ni4351 to measure RTD and TC. Hope NI improves new supports for old boards while producting new boards.

Best Regards!

papaya