Arch Linux

Tomin

Member

Registered: 2012-10-21

Posts: 16

[SOLVED] Problems with usb serial

I hadn't used my Arduino for some time, but yesterday I tried to connect it to my laptop (Arch Linux, 3.9.8-1-ARCH, systemd 204). No /dev/ttyACM[0-9]-device is showing up (Arduino Uno) nor /dev/ttyUSB0 is. Then I tried a generic USB serial stick and it didn't work either. I tried both of them on my desktop (Ubuntu 13.04, 3.8.0) and they work just fine. Do you have any idea why they don't work with my laptop?

Here are new lines from dmesg when I connect the usb serial adapter:

[16461.200050] ehci-pci 0000:00:1a.7: power state changed by ACPI to D0
[16461.301997] ehci-pci 0000:00:1a.7: setting latency timer to 64
[16461.302215] ehci-pci 0000:00:1d.7: power state changed by ACPI to D0
[16461.315120] ehci-pci 0000:00:1a.7: power state changed by ACPI to D3cold
[16461.405284] ehci-pci 0000:00:1d.7: setting latency timer to 64
[16461.562581] uhci_hcd 0000:00:1d.0: power state changed by ACPI to D0
[16461.563776] uhci_hcd 0000:00:1d.0: setting latency timer to 64
[16461.911792] ehci-pci 0000:00:1d.7: power state changed by ACPI to D3cold
[16461.991796] usb 3-2: new full-speed USB device number 24 using uhci_hcd

and line from lsusb (yes, it is there):

Bus 003 Device 024: ID 10c4:ea60 Cygnal Integrated Products, Inc. CP210x UART Bridge / myAVR mySmartUSB light

and no /dev/ttyUSB[0-9] device:

$ ls /dev/tty{ACM,USB}*
ls: tiedostoa /dev/ttyACM* ei voi käsitellä: Tiedostoa tai hakemistoa ei ole
ls: tiedostoa /dev/ttyUSB* ei voi käsitellä: Tiedostoa tai hakemistoa ei ole

Last edited by Tomin (2013-07-06 17:16:58)

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 20,690

Re: [SOLVED] Problems with usb serial

Any chance that the kernel you are actually running is different than the libraries that are installed?

Compare the kernel revisions reported by uname -a and  pacman -Qi linux and ensure they match.  My suspicion is that the appropriate kernel module is failing to load.

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Tomin

Member

Registered: 2012-10-21

Posts: 16

Re: [SOLVED] Problems with usb serial

Indeed that was the problem. I hadn't rebooted after kernel updates. Now it works fine. Thanks.