Note able to detect USB Ports in terminal using command `ls /dev/ttyUSB*` getting error ls: cannot access '/dev/ttyUSB*': No such file or directory

Robotics & Edge Computing Jetson Systems Jetson AGX Orin
1

NVIDIA Jetson AGX Orin Developer Kit

Hi I am trying to sent data from USB port of jetson to a C type port of external device (laptop) using python pySerial package.

But while trying to list the available usb ports using ls /dev/ttyUSB* I am getting getting error ls: cannot access ‘/dev/ttyUSB*’: No such file or directory.

But when I connected c to c cable from the following path /dev/ttyGS0 I was able to detect the c-type port at jetson.

How to detect the USB ports do we need to install any special drivers for these.

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Is there any /dev/ttyACMx node on your host?

4

Thanks for checking this

These are the following available paths

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we dont have ACMx, but have AMA0

5

Just to clarify… do you see any log on your host “dmesg” when you connect Jetson usb cable to it?

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And one more thing to confirm. Which port is connected on Jetson side with your cable?

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When we connect c to c its shows valid logs for Linux for tegra

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But when we connect USB to c

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the same not detected

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We tried the following port

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9

Are you trying to let Jetson be a USB device or a USB host?

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we are trying to communicate from jetson USB port to laptop c type port

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Ok. If you cannot understand my question, just follow what I said.

The only port that will reveal as /dev/ttyACMx node is the type C port on Jetson.

You won’t see anything coming out on your host if you connect a type A port on Jetson.

Is it okay to understand above?

12

Thanks, does it mean that Type A ports are not meant for data transfer from jetson to external device

13

You need some knowledge about how USB is working…
It is not related to Jetson but every other USB devices too.

USB type A port by its nature is a role of usb host.

Micro usb or type C usb port supports OTG, which means it could be either usb host or usb device. The role is decided during the pin connection.

If you connect type A port on Jetson and type C port on your host PC, then actually the one that plays as “usb host” is Jetson… And such /dev/ttyUSBx or ACMx shall appear on “Jetson” but not your host.
However, this is not normal usecase so I am not sure if Jetson side and your host side have sufficient driver to do this.

Thus, you should let host PC side be USB host and Jetson be USB device…

14

Got it thanks a lot