Hi all,
I have been off the forum for quite a while, but am slowly inching my way back up to date. I thought I'd begin by sharing a problem I encountered, and the solution I found.
We have multiple Windows PCs running several versions of LabVIEW runtime and diverse executables. The executables largely carry out slow data acquisition, control, monitoring, and data logging activities. We use mainly NI compact DAQ or USB devices, plus a variety of other instruments like Agilent data loggers and HP optical power meters. Connections are typically USB, RS-232, or GPIB.
We started seeing that a very small number of our LabVIEW executables (runtime 2020 or 2024 Q3 64 bit) would stop acquiring and logging data after the screen timed out and locked (10 minutes). This affected software written at different periods spanning a decade, by multiple developers in 2013, 2020 and 2024Q3 LabVIEW, with architectures spanning simple loops and sequence diagrams all the way up to DQMH plus OOP. The machines are Windows 10 or 11, and get monthly updates, but no BIOS settings are changed by the updates. Most executables remained unaffected. The behaviour is repeatable with specific executables, but is independent of machine or operating system.
We could not correlate the appearance of this problem with any particular event.
I went down a very deep rabbit hole changing cables, hardware and software. Finally I looked at possible DAQmx timeouts. I went into the BIOS and made three changes. I don't know which one made the difference, but afterwards the problem went away for all of the affected software.
To prevent LabVIEW executables from freezing upon screen timeout I made the following changes to the BIOS:
- Enable USB Powershare
- Block Sleep
- Disable Sleep Control
This cost us a lot of time and frustration. I still don't fully understand what happened, but this made it go away. I guess our machines will consume a bit more electricity, but we can continue our work.
I hope this helps someone.
Eamonn McKernan
