We have a PC-based test system that occasionally loses the ability to talk to the USB instruments. I started noticing that when this happens, the USB Power is also off for the Mouse and the Keyboard.
- PC: NISE-3500 Fanless Embedded PC
- Chipset: Intel QM57
- USB Driver: Intel 5 Series / 3400 Series Chipset Family USB Enhanced Host Controller - 3B3C
- OS: Windows 7
I tried to searching the Windows Event Log and could not find anything.
When the problem occurs it takes out ALL the USB ports on the system. I believe the PC only has one USB chip/controller; but, has 6 ports. All of the instruments and devices are on their own port.
I suspect that the cause is something like a USB over-current or USB stack violation that is causing the system to disable everything; but, I have not figured out a way to identify/confirm that.
Any ideas what can cause this and how to trace the problem.
Note: One of the instruments was developed (along with the Driver) by a partner group in Germany. It is a likely culprit; but, I don't have access to the Driver code and I am not sure how much support I can get from them unless I can find a smoking gun.