NI PXIe Cards refused to load its FPGA firmware when using Remote Desktop - Page 1
Forum section: electronics / testgear

author: TerayTech
author_rank: Newbie
timestamp: August 08, 2025, 06:59:14 am
content: Today I ran into a very strange bug.After reading a previous thread here (https://www.eevblog.com/forum/rf-microwave/ni-vector-signal-transceiver/), I built my own PXIe-5644R setup.For the controller, I used a cheap second-hand Intel NUC6i7KYK. It has two M.2 slots — which is great, because one can hold an NVMe SSD, and the other can be used with a PCIe x4 riser cable to connect the PXIe card.Initially, everything worked perfectly. I used a portable monitor connected via Thunderbolt 3 (single cable for power and video), and the display worked fine. The instrument also functioned without issues.Later, I moved to a new place. Since I couldn’t keep the portable monitor permanently on my desk, I decided to use remote desktop instead which is pretty common in NI instruments. To prevent the GPU from disabling itself when no display is connected, I plugged in an HDMI dummy load (a small device with a microcontroller that sends fake EDID data over HDMI I²C).I had already configured Splashtop Streamer for remote access, so after reconnecting it to Wi-Fi, I expected to control it remotely for testing.However, today when I powered it up, it refused to work properly.The exact details can be seen in the attached pictures.Symptoms:On startup, find the device in NI MAX reports an error.The firmware version shows as ff.ff.ff.ff.QuoteThe error message says the firmware is “too new” — but this seems to be caused by the firmware failing to load at all.and the temperature readings are unavailable.However, using tools like AIDA64, I can still see the PCIe x4 device listed in the system hardware. That means the fpga in the card is working correctly while boot, since if it doesn't boot the firmware in the flash, it won't showed up in pcie devices listAfter spending the entire morning troubleshooting, I noticed a subtle but important clue:Normally, after a reboot, I connect via remote desktop right away. The moment the remote connection is established, I saw the PXIe card’s ACCESS LED blink briefly — going from its default green (after power-on), turning off, then lighting up again.This made me suspect the problem might be related to remote desktop.Sure enough, when I connected a real HDMI monitor and logged into Windows manually, the problem disappeared — the FPGA firmware loaded correctly, and the instrument worked as expected.Remote access is still usable after manually login during startup, and won't affect on the stabilityI have tried this several times, and this issue can be reliably reproduced and solved on my setup.This is incredibly strange. I searched the entire internet for this failure mode and error code, but found absolutely nothing — no documentation, no solutions. So I decided to post it here in case someone else encounters the same thing. Hopefully this will help you.I’m still not entirely sure why this bug happens. Could it be related to Windows login permissions when using remote desktop? Could PCIe device initialization somehow depend on this? I don’t know. If anyone here understands what’s going on, please share your thoughts.

author: coromonadalix
author_rank: Super Contributor
timestamp: August 08, 2025, 10:00:18 am
content: can you delay your remote desktop start wayyy after your setup boot process ?

author: TerayTech
author_rank: Newbie
timestamp: August 13, 2025, 01:26:58 am
content: I have some updates today.Well in the previous days I've tried several different remote softwares including: RDP(come with Windows) and Orayboth of them works when trying to boot into windows with remote login.I've noticed a new point that the NI PXIe-5644r card easily triggers a reset if I plug-in the SMA connector. This could be caused by grounding issues, that both NI card and my spectrum analyzer are using individual power adapters, expecially for my spectrum analyzer, its adapter doesn't come with a ground connection.And after it resets itself, the fpga firmware is nolonger can be loaded.So i guess, the FPGA firmware was loaded once when normal booting. And need more steps to load after booted and reset.When the splashtop software was loaded, it triggered NI card to reset, and caused all of this problem.I don't know what is needed to reload the firmware after boot? Maybe it requires PXIe_trig signals? Or PXIe_100M clock signal? Which my DIY adapter board doesn't have yet.To be continued...