Why do USB-C hubs still have USB 2.0 ports? (2021)

Re:Why do USB-C hubs still have USB 2.0 ports? (2021) by eigen on Tuesday May 10, 2022 @09:37PM (#31334884)

doesnt §4.6 of the USB-C spec show the precedence of power source usage? I.E. there is no 10W option, just 3A, 1.5A, 0.9A, 0.5A at 5V or 15W, 7.5W, 4.5W, or 2.5W. so then your 15W port turns into 2x 7.5W ports or 3x 5W ports. I dont know if you can count on the upstream port being 15W. if its 7.5W do you do 4.5+2.5W and 3x 2.5W?

also, I've found that no one obeys the current limit for inrush so now your downstream ports have to allow 7.5+W until they enumerate and you can lower the current limit.

additionally, people are complaining about not being able to tell cables apart. can they tell the power requirements and calculate how much power a combination of devices requires?

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Re:Why do USB-C hubs still have USB 2.0 ports? (2021) by Dylan16807 on Tuesday May 10, 2022 @10:32PM (#31335217)

Those are only for dumb power supplies using resistors to signal max amount. Negotiated power is very granular.

> additionally, people are complaining about not being able to tell cables apart. can they tell the power requirements and calculate how much power a combination of devices requires?

If they don't know device power levels they can just learn what can simultaneously go on a single port when they try, like with USB 2.

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