Can you get me in touch with someone at TI that might be able to answer these questions about turning on the compliance packets on the upstream port on this USB hub I designed using TI p/n TUSB8040A1RKMR based on the eval board.
We decided to have some electrical testing done on the Hub board I designed to rule out any Hub board design issues while looking in to some minor USB connection issues we have been seeing with our cameras.
Apparently the test facility cannot enable the compliance packets. Here are the relevant test engineer’s comments. Full emails are below.
“… we also use Compliance Packets or CP#(e.g. CP1, CP2, CP0, etc) to put ports into repeatable test states. While I was able to test upstream port in a loopback state and test the LFPS signal, I was not able to get the port into any of the Compliance Packets.”
“You might need to talk to your silicon provider to see if there is something special we need to do to turn on CP#s. From the looks of it, you are using Texas Instruments silicon, specifically the TUSB8040A1. I have not used this model of hub silicon before, but I have used various development platforms from TI in the past and they all supported Compliance Packets, so there might just be something that needs to be turned on for this. You will also want to make sure that both upstream and downstream Compliance packets are turned on.”
