scxi 1126 frequency measurement along with other scxi modules

[Bipin]

I want to measure frequency signal using sxci 1126. I have gone through the example code for sxci 1126. I am using NI-DAQ and Labview 7.1.

The example code is applicable when am acquiring only from 1126. I have to acquire data also from 1102 102B along with 1126.

In the example code along with AI config.vi and Ai Start.vi there are two additional vi's like AI paramete.vi and AI Trigger config.vi I understand that they are used for reading from 1126. My worry is how this is going to affect my acquisition from other scxi modules as all the modules are in multiplexed mode.

[Salvador_Santolucito]

Your data acquisition should not be effected. Are you trying to trigger just the 1126? Or do you have the other SCXI modules acquiring at the same time?

[Bipin]

Yes, I have other modules acquiring at the same time. I want to know how the additional vi's that I have to use for 1126 will effect acquisition from other modules. Thanks in advance.

[Salvador_Santolucito]

Bipin,

You will be accessing all of your SCXI boards through the same MIO board. This means that you will need to put all of your acquisitions in the same task. The acquisition from each module will be multiplexed into the DAQ board.

[Bipin]

I know that all scxi channel data is available in daq board channel 0 in multiplexed mode if there is only one scxi chassis.

What I asked was how is the presence of 1126 module in mutiplexed mode going to effect acquisition from other modules. Kindly go through the SCXI-1126 frequency.vi that is attached this exapmple is when you are acquiring only from 1126 module.

Now coming back to my question In the above mentioned example there are two vi's named ai parameter.vi and ai Trigger config.vi. Now how is the presence of these vi's going to effect configuration from other scxi modules as I do not need these for aquisition from 1102 and 1102b modules normally.

If possible send me a vi that acquires from 1126 and 1102 module simultan
eously in multiplexed also I am using traditional NI DAQ with Labview 7.1.

[Salvador_Santolucito]

Hi Bipin,

Looking at your code, I see that you are still using Traditional DAQ. Since you have LV 7.1, you can take advantage of the new features of DAQmx.

With DAQmx, you can create a virtual task that includes all of the different types of measurements you want to make. Once you set up the task in MAX, you can place it on the block diagram and automatically generate the code necessary to execute this.

To do this, open up the Measurement and Automation Exlporer (MAX). Select "Data Neighborhood" from the tree on the left. Then click the button labeled "Create New." Create a DAQmx Virtual Channel. Follow the series of menus to set up your first type of acquisition (1126 frequency measurement). When you are
done creating the task, you can add the second type of measurement to that same task. In the task config page, you will see a white box with the name of the channel you just created in it. Above the name you will see an "Add" button. Click on this button and follow the menus to set up your second measurement (1102 module).

Once they are set up, save the task and open LabVIEW. Place the DAQmx Task Name constant on your block diagram found in All Functions >> Data Acquisition >> DAQmx... the task name constant is a purple colored box. Clicking on the box once its on the block diagram will expand a menu that will let you choose your task. Once selected, right click on the task name and choose Generate Code >> Example. This will automatically generate the code necessary to run the tasks. Simply hit the run button and enjoy!

Thanks,
Sal

[Bipin]

Thanks for your reply. what do i do if i am creating an exe. Do I have to generate the code again and again if there is any change in the scxi module configuration. Can you suggest me a solution using traditional daq as i am comfortable using traditional daq.

regards,

Bipin

[Salvador_Santolucito]

If you are creating an .exe file with your application nothing should change. It will work without problems on the same PC. If you move the executable to another PC you will need to make sure the target PC has the same hardware configuration so the program uses the correct device numbers. You can make also export the hardware config on the development pc and then import it into the target pc to accomplish this.

I would suggest using the DAQmx programming. Once you get used to it, it is much easier. Also, it provides added functionality that traditional DAQ does not. Many of the "nitty gritty" things we had to worry about in Traditional DAQ are taken care of automatically in DAQmx.