How many full speed USB 3 ports does the jetson TX2 module have?

Hey there,

we bought a jetson TX2 dev kit and wanted to use 3 cameras over USB. 2x Realsense and one higher resolution cameras. We noticed that we ran into bandwidth problems with 1080p@60fps connecting all the cameras over a USB hub. The dev kit for whatever reason only has one USB 3 port available. We were thinking about getting one of these: https://auvidea.eu/product/70720/

Question:
If buying the carrier board with 4 USB3 ports, do we get the full USB 3 speed for each of those? Does the jetson TX2 module support 4 USB connections simultaneously each at 5000M or would all of the ports share the bandwidth?

Thanks.

Hi,
Please check
https://devtalk.nvidia.com/default/topic/1068466/

usb3-1 and usb3-2 share 5Gb/s bandwidth. usb3-0 has one full 5Gb/s.

FYI, what you are asking for would be “independent root HUBs”. See “lsusb -t” and note if the same root_hub is shared or separate.

If you want more root_hub support, then you could use a PCIe USB3 add-on card. Not all such USB add-on cards are the same, some are just a single root HUB sharing ports. The better ones use independent root HUBs. You can bet that any PCIe x1 lane add-on is unable to provide multiple ports which are independent. An x2 lane count might, but the PCIe mode, if it were to slow down, might not get full performance. Any such card with x4 PCIe lane count would presumably do everything you want, but I have also seen “fake” low end cards like this…they say x4, and look x4, but in reality “lsusb -t” will show they are a single lane. Go for a known brand PCIe x4 USB3 card.

Hey guys,

thanks a lot for the answers. Understood.

Then I guess I just need to make sure the carrier board I posted does support this? The description (https://auvidea.eu/j130-with-4k-and-2k-video-input/) just says they are using this controller Cypress CYUSB3304-68LTXC (https://www.cypress.com/file/141031/download)

From the datasheet it says
4 ports in total: All ports support SS (5 Gbps), and are backward-compatiblewith HS (480 Mbps), FS (12 Mbps), and LS (1.5 Mbps)

Okay quick update, I finally reached someeone there.
They told me that the for USB A share one usb root hub and then the micro USB port is connected to the other root hub. Which is kinda interesting because on the nvidia dev kit this seems to be only a micro USB 2 port.

Not sure but the board may be specific to TX1. You may look for boards for TX2.

It is also possible the board vendor uses PCIe to USB chip for extending more USB3 ports.

AAEON makes a small system https://www.aaeon.com/en/p/nvidia-jetson-nano-embedded-box-pc-boxer-8221ai with a carrier board that has 4 USB 3 connectors. In looking at the pinout of the Jetson Nano CPU Module Connector in the Manual on page 19, http://data-us.aaeon.com/DOWNLOAD/MANUAL/BOXER-8221AI%20Manual%202nd%20Ed.pdf , it shows pin-outs for 3 USB: USB0, USB1 and USB2.