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July 30 2010

Sven
So you integrate a 2 ports USB hub into every connector, huh? Nice concept, but it doesn't work for USB.

Due to the mandatory overload protection FET for every downstream port you loose about 0.5V with every "connector", but USB requires at least 4.25V on the power lines. Also you can't chain more than 5 hubs.

What all this means is: To stay within the USB specs, you can chain only 2 of those plugs if they comply to overcurrent protection rules. And more than 5 of those can't be properly enumerated anyway.

Despite it's name USB is not a Bus. It's a host controlled tree.

What you need for this would be a true bus with unlimited stacking and tapping depth. Guess what, there is such a thing by far superior to USB but it never got the proper support by hardware designers: IEEE1394 aka FireWire.
Reposted fromdatenwolf datenwolf viaak ak