Raspberry Pi Forums

It seems many of the "nicer" hubs out there are now 3.0 and that seems to be a problem for my pi. I am running my hard drive off of it with /boot the only thing on the SD card and the high speed devices run great. The problem is with the slow speed devices such as keyboards, FT232, chips etc. They do not enumerate properly. If I plug another 2.0 cheap hub into my 3.0 hub, I can plug slow devices into that without issues. I thought I would be tricky and plug the 2.0 hub into the pi and the 3.0 hub into it, but slow devices are still not happy. I have kept the pi up to date, even rpi-update but that doesn't help.

Yes I do know the pi is only USB 2.0, but has any progress been made on this?

markatlnk wrote:Yes I do know the pi is only USB 2.0, but has any progress been made on this?

The Raspberry Pi still only has USB 2.0 ports and that's all it ever will have. What kind of progress are you expecting?

The expected thing is for the slow speed devices such as keyboards to function when plugged into a 3.0 hub. I also frequently use FT232 USB to serial adapters that are supported by the pi, but do not work if plugged directly into a 3.0 hub.

I am know the pi is 2.0 and that is fine, but some of my better hubs have much more robust power supplies that power the pi and external hard drives very well. The problem is only with the very slow devices. The hubs I have work with the slow devices just fine when plugged into another computer such as my mac, just not the pi.

This isn't a speed issue, it is an enumeration issue.

At the moment I am using an Anker 7 port 3.0 USB hub. It has a 12Vdc input supply that is converted to 5 volts inside the hub. I also split off the 12V to drive the 7" monitor for my setup. The SD card only has the /boot directory on it and everything else is on a 1TB external hard drive. I am just attempting to avoid adding an additional hub to the system for the slower things.

Mark

Are you using the latest firmware? Should be more robust than earlier versions.

Yup, just did:

apt-get update
apt-get upgrade
rpi-update

and tested again, still doesn't like the slow stuff.

There seems to be frequent updates, so I test it frequently.

If you have any other ideas of how to test it or more wish lsusb dumps (don't show anything) or dmesg dumps, (they say it couldn't enumerate). The hub has a light per port, and it briefly light up, then go back out (should stay lit).

Dunno, but I do seem to remember something about 3.0 hubs that makes them problematic with 1.0 devices. I'll ping P33M and ask him to comment. He is the expert.

There is a known issue when using USB3.0 hubs with FS or LS devices:

https://github.com/raspberrypi/firmware ... t-24920727

I have seen that post, and do understand that there is a known issue. But firmware gets updated all the time, and new 3.0 hubs also come out. The early 3.0 hubs don't work well with my mac, but the new ones work great. Is it the pi or is it the 3.0 hubs that aren't following the specs?

If I plug the 3.0 hub into my CentOS box with 2.0 hubs, it works fine with slow speed devices. This leads me to believe that it is an issue with the pi.

Don't get me wrong, I love my pi, it isn't a show stopper, just something I am trying to figure out.

From the comment linked, the evidence is that the hub fails to follow the specification for inter-packet gap timeouts.

USB3.0 hubs are the subject of firmware updates - USB2.0 hubs use a hardcoded state machine design which requires no programmability. It is possible that a future hub firmware update may resolve the issue.