USB2Test Transceiver errors when multiple USB devices attached during test run

[BASUser]

I am testing a series of 3 USB ports on a system where one of those ports has a PMUSB02 (rev 2) device for the USB2Test and another USB port has a keyboard and the third is empty.

Should I expect to get transceiver errors during the test when the keyboard is attached?

Currently, if the keyboard is not attached during the test there are no errors, but if the keyboard is attached during the test, I get transceiver errors.

Can someone help me understand if this is expected and why?

Thank you!

[David (PassMark)]

It might be that the keyboard is a USB1.0 device using 1.5 Mbit/s (called Low Speed) or 12 Mbit/s (called Full Speed). Having mixed devices is known to cause some issues.

Did you try different keyboard?

It should be noted that device transceiver errors are not an indication that the USB port does not comply with the USB Specification. Rather that further investigation may be required.

[BASUser]

David,

Thank you for that information. This was indeed the problem. All my devices I tested seem to be USB1.0 devices. I did not get any transceiver errors using USB 2.0 and 3.0 devices. Thanks again!