1010 chassis, PXI-6052E; accessing unused AI channels

[chassan]

Hello folks,

I have a 1010 (PXI/SCXI combo) chassis with a PXI-6052E installed in slot 8.  The 6052E connector is wired to a 68-pin terminal board.  If I use the scxi modules in mulitplexed mode, can I use the other 6052E analog input channels to measure other signals?

I have seen the documents regarding direct wiring of a "separate" scxi chassis directly wired to a daq card, but I haven't found any information about the 1010 chassis and the availability of (presumably) unused daq channels.

Any documentation regarding this would be greatly appreciated!

Best Regards,

Chris

[jschwartz]

Hi Chris,

The KnowledgeBase located here should answer your question.

[chassan]

Hi Jim,

Thanks for the link (I hadn't found that one)!

The following is an excerpt from the link:

"M-Series
PXI/SCXI combo chassis use a local bus on the backplane of the chassis to control SCXI data. As a result, M-Series PXI DAQ cards don't reserve any digital lines for SCXI controls. Therefore, any analog, digital or counter channel on the controlling M-Series PXI DAQ card can be connected at the front of the card, with the exception of Analog Input Channel 0.

E-Series
E-Series PXI DAQ cards behave differently than M-Series. Like their PCI equivalents, E-Series PXI DAQ cards reserve DIO lines 0, 1, 2, and 4 from Port 0, and the Frequency Output line. All other analog, digital and counter channels are accessible from the front connector. Again, use caution when wiring signals to the cards' front connectors since it is possible to wire a digital signal to a reserved line and corrupt the data coming from the SCXI.
"

It states specifically for the M-Series that any DIO or AI except for AI0 can be used.  However, for the E-Series it simply cautions the user to not connect to a reserved line.  Where can I find out what the reserved lines are?

Thanks,

Chris

[EEsRULEtheWORLD]

Hi, Chris.

For E-series devices, when you have any multifunction DAQ board configured to control an SCXI chassis, lines 0, 1, 2, and 4 on port 0 are reserved.  If you try to access these reserved lines from the DAQ board's test panel in MAX, the reserved lines will either be grayed out, or you will receive an error when trying to use them.  Lines 0, 1, 2 and 4 on port 0 are equivalent to P0.0, P0.1, P0.2 and P0.4, respectively.  These particular reserved lines are circled in red in the pin-out of the PXI-6052E below:

Let me know if you need any more information.  I hope you're having a great day!

[chassan]

Hi Sara,

Thanks for the information, and I hope you're having a great day too.  I understand the reserved digital lines; However, I haven't been able to find out which analog input lines are reserved, and this is the real point of interest.

Here is my setup: 

I have the pxi-6052E plugged into slot 8 of the 1010 chassis.  The scxi signals must come into the 6052E through the backplane since I can measure scxi signals without manually making connections between the scxi and the 6052E.  The front connector of the 6052E is connected to a 68-pin breakout (terminal) board.

Here is what I'm trying to understand:

With this setup, the 6052E card is used to digitize the (multiplexed) signals from the scxi side of the 1010 chassis.  I'd like to use any "unreserved" analog input channels on the 6052E to measure signals wired to the analog input pins of the 68-pin terminal block.  What I'm trying to find out is which analog inputs I can use and which are "reserved" for the scxi signals.

Best Regards,

Chris 

[EEsRULEtheWORLD]

Hi, Chris.

The PXI-6052E is an E-series device; therefore, the only reserved lines on the PXI-6052E are going to be DIO lines 0, 1, 2, and 4 from Port 0.  No analog lines are reserved on E-series devices.  (Note:  If you had an M-series device, Analog Input Channel 0 would be reserved.)

Let me know if you need any more information.

[chassan]

Hi Sara,

I'm a bit confused about how the system knows which analog input channel(s) to use to digitize the scxi signals.  From your previous post, it sounds like the channel(s) used to digitize the scxi signals may be "user selected" instead of pre-defined by the system.  Is this true?  If so, does that mean that I can choose the analog input channel(s) used to digitize the scxi signals and then use the remaining analog inputs to measure other signals?

Best Regards,

Chris

[EEsRULEtheWORLD]

Hi, Chris.

You are correct.  The channel(s) are "user selected."  After installing the DAQmx or traditional DAQ driver, example programs will install to the National Instruments folder on your computer.  Check out some of the examples available to you in this folder for acquiring analog input.  In these examples, you can select the physical channel associated with your PXI-6052E.  You can also configure your physical channel(s) for analog acquisition by creating a task.  If you're using the DAQmx driver, here is a great tutorial on how to create a task using Measurement and Automation Explorer and then incorporate it into LabVIEW.  What Application Development Environment (ADE) are you using?

Let me know if you need any more information.

Message Edited by EEsRULEtheWORLD on 08-07-2009 02:05 PM

[chassan]

Hi Sara,

According to page 16-2 of "DAQ Hardware Overview Guide" (NI, October, 2000),

"A PXI E Series device in slot 8 can sample SCXI analog input channels via a special channel connected to the SCXI bus (ND_PXI_SC).   ...   

If you use the internal connection to the SCXI bus instead of cabling to an SCXI module, all the regular analog input channels on your device are available for other uses."

This does indeed support what stated in your previous post.  I'm pretty sure that there is only one ADC on the 6052E, so the questions now are:

1. What is the channel order in each scan?  For instance, are all of the scxi channels scanned first and then the "regular analog input" channels?

2. Are the channels scanned in consecutive ascending order?

3. Are only the configured channels scanned, or are all of the channels scanned (I read something somewhere about the scxi channels all being scanned consecutively in ascending order whether or not they are actually configured)?

Thanks for all the help!

Chris 

[chassan]

Sara,

By  the way, I'm using LabVIEW 7.1.

Best Regards,

Chris