what purpose do StdA_* serve?
"The most significant physical change from USB 2.0 to USB 3.0 has been the introduction of two differential data pairs called SSRx+/SSRx- and SSTx+/SSTx- to run in parallel with the existing D-/D+ data bus. This allows full duplex simultaneous transfer of data as opposed to the single duplex unidirectional USB 2.0 bus."
And the StdA comes from StandardA type, probably..
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