Watch out for USB controller speed limit!

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Spikee
Posts: 115
Joined: Wed Mar 04, 2015 9:49 am

Watch out for USB controller speed limit!

Post by Spikee »

I was having a bunch of problems with my liteplacer.
After I changed my upcam to the Logitech C270 the control of the liteplacer became really laggy, sometimes it would just stop in the middle what it was doing or crash often.

The problem?
It seems that all the usb (2.0 and 3.0) lines go trough 1 or two controllers. The USB 3.0 Lines did not work so everything was on the 2.0 lines.
The logitech webcam only showed the 1024x xxx settings , now on my laptop it shows the full 3MP.

Looks like there occured some kind of packet overflow causing it to drop USB packets.

Which interrupted commands going to the TinyG etc...

Mind you this is a 8 core AMD , SSD machine so their is enough power. The weak link seems to be the USB controller.

Now on my laptop it works fine. But I might get a USB3.0 hub so I can also hook my headphones to it.


I think others will have simular hardware problems. Especially on old machines.
Spikee
Posts: 115
Joined: Wed Mar 04, 2015 9:49 am

Re: Watch out for USB controller speed limit!

Post by Spikee »

Found new USB 3.0 files. Works without problems now.
mrandt
Posts: 407
Joined: Mon Apr 27, 2015 10:56 am
Location: Stuttgart, Germany

Re: Watch out for USB controller speed limit!

Post by mrandt »

Spikee wrote:Found new USB 3.0 files. Works without problems now.
So it was a driver issue?
Spikee
Posts: 115
Joined: Wed Mar 04, 2015 9:49 am

Re: Watch out for USB controller speed limit!

Post by Spikee »

It was USB controller speed limit on USB 2 /1 controller.

I found new driver for my USB 3.0 ports (other controller) and now the issues are gone.
WayOutWest
Posts: 198
Joined: Thu Jul 16, 2015 12:18 am
Location: Washington State, USA

Re: Watch out for USB controller speed limit!

Post by WayOutWest »

Spikee wrote:It was USB controller speed limit on USB 2 /1 controller.

I found new driver for my USB 3.0 ports (other controller) and now the issues are gone.
I've had the same experience. Even if all of your cameras are USB 2.0, using a USB 3.0 hub to connect them will help.

Most OSes (even Linux) don't know how to use more than a fairly small percentage of the USB bandwidth for isochronous transfers.
- Adam
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