PXIe-8101 Freezing: Looking for New Controller Suggestions

[ElvisMARROQUIN]

Good morning everyone,

In my lab, we have a PXIe-1071 chassis, with a PXIe-8101 controller and a PXI-6281 DAQ card inside.
Lately, we have encountered a serious problem: this controller is continuously freezing, causing issues, especially when we plan experiments overnight and the controller suddenly freezes.

Since this model is old, we want to purchase a new PXIe. However, I have the following questions:

• Is it only necessary to buy a new controller card? Or should we, for precaution, buy the whole set, meaning a New Chassis and a New DAQ card ?
• Which models do you recommend to replace our old PXIe-8101? My team wishes to use PYTHON instead of LabVIEW to interact with the inputs and outputs, so I would like you to recommend a model that is compatible with Python libraries such as niDAQmx, etc.

[Captain_K]

• Is it only necessary to buy a new controller card? Or should we, for precaution, buy the whole set, meaning a New Chassis and a New DAQ card ?
  • All you need is a new PXIe controller if the controller is the only thing giving you problems.
• Which models do you recommend to replace our old PXIe-8101? My team wishes to use PYTHON instead of LabVIEW to interact with the inputs and outputs, so I would like you to recommend a model that is compatible with Python libraries such as niDAQmx, etc.
  • I'd recommend looking at the PXIe-8822 or PXIe-8842. These are pretty similar in design, with the 8842 being the higher performance option. Given the setup as you've described, it doesn't sound like you need anything too crazy, performance wise. Both of these controllers will work in a PXIe-1071 chassis.
  • These controllers are just computers at their heart, so you can select one with Win10 or Win11 installed and you can install the Python libraries onto it.

Here's a table with the specs for the PXIe-8822, PXIe-8842, and PXIe-8862 if you'd like to take a quick look and here's a link to the specs themselves.

[ElvisMARROQUIN]

Thanks for your response.

But I think that installing Windows 10 or Windows 11 + Python libraries wouldn't be a good idea.

My current PXIe 8101 controller runs on the LabVIEW RealTime OS and connects via an Ethernet cable to a computer running a LabVIEW program. This LabVIEW program is responsible for configuring and controlling our experiment in the laboratory.

Therefore, if we replace to a controller with Windows 11 OS, the other computer would no longer be able to control the process using RealTime.

In any case, I would like to know how else I could use Python to interact with the inputs and outputs using the other computer connected via Ethernet to the PXIe controller.

Thank you for your help

[Captain_K]

Ah, okay. The Real Time OS we offer with these newer controllers is now LinuxRT. Phar Lap (which was installed on the 8101) is being deprecated. For the most part, there's parity between these OS when it comes to existing applications. The OS and software installation process is a little different, though. Here's a guide we have that walks through the process.

Migrating PharLap Application to NI Linux RT

Now, I don't work much with RT systems and at those times, I've only ever used LabVIEW and the LabVIEW Real-Time Module. As long as you can find Linux Python interpreters, I image you can run Python code on it. LinuxRT uses the uses the OPKG package manager for which I believe there are interpreters out there.

[ElvisMARROQUIN]

Thank you for your response.

To clarify, I understand that Phar Lap is being deprecated and the current Real-Time OS for new PXIe controllers is NI Linux Real-Time (LinuxRT).

My main concern is the communication between the new LinuxRT-based PXIe controller and our existing computer that runs a LabVIEW program. This LabVIEW program is critical as it configures and controls our experiment by interacting with the Real-Time OS on the PXIe controller, and it manages the I/O of the PXI-6281 card.

Could you please confirm if:

1. LabVIEW on our main computer can seamlessly communicate with the PXIe controller running LinuxRT over Ethernet.
2. Any additional steps or considerations we need to be aware of during this migration.

Thank you for your help.

[DieselPower]

Did you change the program running on the PXI lately?  Many years ago I had a memory leak that would cause the PXI to crash.  Once I removed that leak it stopped freezing.  Can you monitor memory use over time so see if that is the cause?