Reply To: VSG60A stability in CW mode versus multitone

Thanks, Andrew — it really does look like you’re right about it being a data loss problem. This is a reasonably fast quad-core system (i7 Sandy Bridge at 3 GHz running Windows 7 x64) but its USB 3 SS support has always been flaky. Yesterday I discovered that I can’t even use a GPIB-USB-HS adapter on the same root hub without corrupting the data going out to the VSG60A. 🙁 Not much you can do about that.

I’m unfortunately more than familiar with supporting customers with USB streaming problems, myself. As a matter of policy, though, I drop the connection entirely if anything goes wrong. IMO, you don’t need to go to the trouble of checksumming your packets independently of what the USB subsystem already does, but sequence numbers are a good sanity check against dropouts during bulk transfers. Many users will prefer to drop the connection and report an error than to risk breaking phase continuity or other corruption that might go unnoticed until it causes trouble later on. Maybe a warning could be implemented?