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English => Interfaces, Pinouts, Cables => Topic started by: Kiernan on Sep 12, 2015, 21:08

Title: USB 3.0 A male to USB 3.0 A male
Post by: Kiernan on Sep 12, 2015, 21:08
If you wish to network two computers via high speed 3.0 cable, is there a problem running an A male to an A male?

Connecting an external HD to a motherboard always has the A to B. B male from HD external to A male to motherboard.

These pinouts indicate the same power and resistance at both ends.

Are they the same?

Can you use a USB like a Cat 6 cable?
Title: Re: USB 3.0 A male to USB 3.0 A male
Post by: n7hmw on Feb 01, 2016, 03:06
Absolutely NOT!!!

USB defines one end as a host and the other as a device, and there are several device categories. In addition, USB provides power, and multiple signal lines. If you make your own cable as proposed, it will like do damage to one or both computers.

What you are looking for is called a USB bridge cable, which has an interface chip. The bridge chip is basically providing a USB-to-network connection as seen from each computer. In addition, the USB power supplied from each PC are isolated from one another.

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For the record, Cat6 is just a cable, but the devices themselves define which pins are transmit and which are receive. In the old days, a PC-to-PC cable needed to be a crossover cable, swapping the transmit and receive pairs. This is still strictly the case now, however, many PC-based Ethernet ports can autodetect the connection and swap the pairs, just as Ethernet switches have been able to do for many years now.

Non-Ethernet uses of structured cabling do not necessarily allow this.