PXI RTSI Triggering

[4BoysDad]

Hi;

I have a PXIe-1065 with the following modules: PXI-6529, PXI-6280, PXI-5114, & PXI-6713. I have 3 questions:

1. How is the RTSI trigger initiated?

2. How can this trigger be monitored?

3. How do I create an RTSI triggered task?

I am fairly new to LabVIEW but I am working with other more experienced programmers.

Thank you for any help.

4BoysDad

[Jim_S · Accepted solution]

Hello 4BoysDad,

Before we talk about your questions, I am going to provide some information about the cards you have because I think it will help me answer the questions completely. First, the PXI-6529, PXI-6280, PXI-6713 use the DAQmx driver but the PXI-5114 is a Digitizer and uses the NI-Scope driver. Knowing this, I would focus on passing the trigger between the 3 DAQmx cards first before thinking about the PXI-5114.

Along with this, you have a PXIe-1065 chassis. With this chassis, there are 3 trigger bus segments which basically divide up the backplane. If one of these cards are in a different segment, you are going to need to correct the bus segments together to pass the trigger through the backplane. To see how the backplane it broken up please look at the data sheet for the PXIe-1065. I would recommend that you place them on one PXI trigger bus segment.

Knowing this, here are my responses to the questions:

1.) How is the RTSI trigger initiated? How do I create an RTSI triggered task?

Before doing this, you will need to select a Master device for the other Slave devices. If the master device is a DAQmx device and you are passing it to another DAQmx slaves, here is an example how to implement this. The trigger will be initiated by the Master device and in this example, the trigger is an arm start trigger (For more information on this, please consult the DAQmx Help). When looking at this example, the RTSI trigger management is done in the Sync Tasks- Trig Skew Corrections. Along with RTSI trigger, this VI also allows you to sync the reference clocks of each of the devices. Since this example provides detailed notes as well as step by step instructions how it works, I won't repeat the information here.

If you want to synchronize the Scope card with a DAQmx device or multiple devices, you will need to export the signal to the other card. This example explains how to implement the Scope as a Master and the DAQmx device as the slave. Like the other explain, it provides an general explanation how to perform this as well as step by step instructions how to implement this.

2.) How can this trigger be monitored?

As for monitoring the trigger, I have looked into the DAQmx and the Scope driver as well as consulted with my colleagues and there isn't a function we have found that will tell you that the trigger has been sent. One way we have found to check this is to use the timeout for the task/sessions to see if they have started. If they haven't the trigger hasn't been sent to the other device yet. Are you looking for this functionality for debugging purposes or are you going to use this in your program somehow?

If you have any more questions about this, feel free to post.

[4BoysDad]

Dear Jim;

Thank you for the insight.

I will pass on your thoughts to our LabVIEW Guru.

I'm a LabVIEW newbie. Someday I will understand all this. I am reading LabVIEW for Everyone to try and get up the curve faster.

Steve

Hiawatha, IA

[4BoysDad]

Dear Jim;

I want to PLL the 1065's 10 Mhz clock to the 5114's 250 Mhz internal clock. Is it possible to route the 1065's 10Mhz clock to the 5114's rtsi7 line?

Thank you,

Steve

[4BoysDad]

Dear Jim;

In the PXIe-165 chassis, I have the following:

Slot 1 = PXIe-8102

Slot 2 = PXI-6529

Slot 3 = PXI-6280

Slot 4 = PXI-6280

Slot 5 = PXI-5114

Slot 6 = PXI-6220

I also have a cDAQ-9178 with the following:

Slot 1 = 9225

Slot 2 = 9227

Slot 3 = 9225

Slot 4 = 9227

So, Know I have the PXIe-1065 10MHz clock PPLd to the 5114's internal 250MHz clock and the triggering which you've explained above.

Steve

[R Sandoval]

Hello Steve,

The internal circuitry of the PXI-5114 does not allow the 10 MHz clock to PLL with the 250MHz clock internally.  Please refer to the following link which displays the clocking diagram of the PXI-5114.

http://zone.ni.com/reference/en-XX/help/370592N-01/digitizers/5114pci_clocking/

Further stablizing the 10 MHz shared referenced is often achieved using timing and sync cards (see below):

PXI Timing and Synchronization

http://sine.ni.com/nips/cds/view/p/lang/en/nid/13332

PXI and PXI Express Timing and Synchronization Control

http://www.ni.com/pdf/products/us/pxi665x_pxie6672_datasheet.pdf

The timing and sync card should be housed in Slot 14 (PXI Express System Timing Slot) as described in the PXIe-1065 user manual on page 1-4 and 1-8:

http://www.ni.com/pdf/manuals/371990c.pdf