3 PXI 2576 Switching cards

[jimmy400]

I have 3 PXI switching cards of the 2756 type. If I swap the cards in the PXI chasis,

how will it affect my switch matrix?

[JasonWhite]

Jimmy,

I think that we'll need a little more information to answer your question. 

• First off, the PXI-2576 is a multi-bank multiplexer and not a matrix.  You could possibly have it configured up as a matrix through multiple modules and cabling, but I wanted to make sure that you knew that it was not a matrix natively.
• If your question is simply regarding the slot location in the chassis, the modules can be located in any slots in your chassis.  The location is not important.
• If your question is regarding whether or not you can replace an old module with a new one and keep the same functionality, the answer is yes.  Once you place the new module in your chassis, you'll want to go into the Measurement and Automation Explorer (MAX) and make sure that your new device has the same device name as your old device and rename it if necessary (located under "NI-DAQmx Devices").  This will ensure software compatibility.

If this doesn't answer your question, feel free to respond with more details.

Jason

[jimmy400]

Jason,

Thanks.  Here is a more coplete story.

I have a switch matrix made of 3 identical cards, which are PXI-2576.  Two cards have the same

configuration and one is different.   Two cards have pxi2576_2w_64x1_mux configuration and

the other one has pxi2576-2w_8x1_mux configuration.

Currently, I do not have the cards, therefore I am doing everything in software. So what I am calling cards

are basically logical names defined in the main NISE software tree under "IVI Drivers", "Logical Names" ... I have defined all the

channels, the routes etc etc for each of the 3 cards and all is good.

What I wanna know is once I get the physical cards, how is the card's physical address bound to a logical name?

And how does NISE know to associate C1 with what slot in the physical PXI chasis??

thnx

[chericks1]

Hi Jimmy400,

1.  What I wanna know is once I get the physical cards, how is the card's physical address bound to a logical name?

As shown in the attached picture "Driver Sessions and Resource Descriptors.JPG", the NI Switch Executive Virtual Device references system hardware using an IVI Logical Name (i.e. C1).  This IVI Logical Name references an IVI Driver Session, and within the Driver Session, a Resource Descriptor is stored.  The Resource Descriptors should exactly match the NI-DAQmx Device names for the NI PXI-2576 modules in your system.

So, for the example of the PXI-2576 with the IVI Logical Name of C1, the Resource Descriptor of interest is 2576_64x1A.  Clicking on 2576_64x1A under NI-DAQmx Devices shows this PXI-2576 switch module is located in PXI chassis 1, PXI slot 2.  "Chassis and Slot Numbers.JPG" displays this configuration information.

2.  And how does NISE know to associate C1 with what slot in the physical PXI chasis??

NISE depends on the IVI configuration, and specifically on the Resource Descriptor, to associate C1 with a physical PXI chassis and slot number.

Hope this helps!

Chad Erickson
Switch Product Support Engineer
NI - USA