Convert USB 3.0 to USB 2.0? Why?

Question

Convert USB 3.0 to USB 2.0? Why?

Sounds useless, since most USB 3.0 devices are backward compatible. But apparently there's enough slop in the spec so that at least my 3.0 HD won't work with my Netgear WNDR4000 N700 router's USB 2.0 port, and I can't mount it as a network drive on my Macbook Pro Retina. You'd expect that the compatibility is achieved by some part of the doohickies ignoring the 3.0 connections and shuffling control signals to their 2.0 counterparts. In any case, the Netgear's not smart enough to do that or something.

Ideally, what I'd like is to have my USB 3.0 HDD plugged into the router so I could do wireless Time Machine backups like a Timecapsule, but take that portable 3.0 HDD along with me and do wired backups and restorals with the speedy 3.0 interface on the road or when I had to do a full restoral. I've tried to fake out the thing by putting a powered USB hub in line, but there's apparently something the Netgear is looking for that the 3.0 HDD doesn't send to allow me to mount that drive wirelessly through the Netgear.

Is there a "smarter" hub that might make the Netgear happy with my portable HD? Or a USB 3.0 to Ethernet converter or someting? I don't expect to find a router with a USB 3.0 interface, considering that extra speed would be wasted going through the wireless interface.

How can I get a drive to be a 2.0 to use it wirelessly via the Netgear, yet 3.0 when I wanted to use it wired directly to my Macbook?

Any ideas?

TIA!

Mark

Posted on Jan 27, 2013 9:31 PM

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Answer 1

Apr 29, 2013 3:35 AM in response to g.Mark Stewart

USB3 is totally independent of USB2. The USB3 host sockets provide both USB3 pins and USB2 pins. USB2 also provides compatibility with USB1. When USB2 and USB3 connections are mated only the USB2 pins connect. When you use a USB3 extension or hub, the USB2 and USB3 signals are routed/buffered/split independently.

A USB2 device can thus be plugged into either a USB2 or USB3 host socket with no problem.

A USB2 compatible USB3 device ditto, but if only USB3 is implement the USB2 can't host.

However, I believe USB3 devices are meant to provide that USB2 backward compatibility.

There is a market/standards hole at the moment for actual conversion between USB2 and USB3, either way.

I haven't been able to find any device that does this - the so called converters just route USB2 signals as needed.

I would like a USB3 to USB2 hub or extension that IGNORED the USB2 host interface and uprated USB2 devices to USB3 signalling - this is dead easy and allows (say) 8 USB cameras or memory sticks to get full high speed USB2 bandwidth from one USB3 controller. But for your inverse problem, there would need to be some more complexity, negotiating the lower bandwidth available and/or buffering and/or handshaking for flow control.

Note USB3 is full duplex, so you have the bandwidth in both directions (so the 8 USB2 cameras could store data back on USB3 disks), whereas USB2 is half duplex (one way).

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Answer 2

LowLuster

Level 6

12,105 points

Apr 29, 2013 3:41 AM in response to g.Mark Stewart

Unless they changes something resently with netgear routers they can not read mac formatted drives. It has to be formatted in one of the windows formats, ntfs or one of the fat formats.

So even if you get the drive mounted to the router and get it mounted as a network drive on your mac time machine would not be able to back up to it as time machine needs a drive formatted mac extended. Also the only network storage solution that time machine can use is a apple time capsule. Otherwise the backup drive has to be connected to the computer for time machine to use it.

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Answer 3

Jan 8, 2014 6:45 AM in response to LowLuster

USB3 radiates the same frequencies used by WiFi and many wireless products, and it also susceptible to them.

In my experience, not a single USB3 hub is reliable due to stupidity of USB3 design. Our disks often "suddenly fall offline" without warning.

AVOID USB3 and if you must use it, use short BEST QUALITY cables, heavily shielded. USB3 has caused repeated trouble in our offices.

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