Arduino Leonardo connected via USB is not detected as TTY

Discussion in 'Troubleshooting' started by sciguy14, Apr 21, 2014.

  1. sciguy14

    sciguy14 New Member

    Apr 21, 2014
    Likes Received:
    Hello friends! I'm using the UDOO (with Ubuntu) for a home automation project. I was previously using the Raspberry Pi, but needed a few more features, and the UDOO fit the bill (and I conveniently had it from the kickstarter campaign). Among other things, I have a BlinkyTape connected to the UDOO via USB. I wrote new firmware for it that stores several LED patterns on the tape, and sending a serial command over the USB TTY connection triggers the selected pattern to play. I've been using this without a problem on the Raspberry Pi. The BlinkyTape uses an Atmel 32U4 with the Arduino Leonardo bootloader, and is identified as such.

    When I plug the BlinkyTape into the UDOO, it's clearly detected as a Leonardo (see dmsg output below), but it appears to be detected as an HID instead of a USB Serial device. This is odd, because when I plug it into a Windows machine, or a raspberry pi (running raspbian) it correctly identifies as USB serial and I can send it serial commands. Since it isn't detected as a USB serial device, a /dev/tty* device is not associated with it, and I can't send serial commands. It also does not appear in the Arduino 1.5 of 1.0.5 IDE port menu listings (it is greyed out). Do you have any idea why this might be happening!? Thanks!

    dmsg Output:
    [ 188.417822] usb 2-1.2: new full speed USB device number 11 using fsl-ehci
    [ 188.538518] input: Arduino LLC Arduino Leonardo as /devices/platform/fsl-ehci.1/usb2/2-1/2-1.2/2-1.2:1.2/input/input4
    [ 188.541804] generic-usb 0003:2341:8036.0007: input,hidraw0: USB HID v1.01 Mouse [Arduino LLC Arduino Leonardo] on usb-fsl-ehci.1-1.2/input2

  2. sciguy14

    sciguy14 New Member

    Apr 21, 2014
    Likes Received:
    Re: Arduino Leonardo connected via USB is not detected as TT

    Got it working! Here's how:

    Got it working! Yay! Here's how. You need to recompile the kernel with usb cdc acm support.

    sudo apt-get install build-essential git libncurses5-dev

    git clone
    cd U-Boot_Unico-2013/
    make -j5 tools
    sudo cp tools/mkimage /usr/local/bin

    cd /usr/src/
    sudo git clone kernel
    cd kernel
    sudo make ARCH=arm UDOO_defconfig
    sudo make ARCH=arm menuconfig
    Device Drivers —> USB support –> USB Modem (CDC ACM) support -> Then Exit and Save when asked.
    sudo make
    sudo make modules_install
    sudo make install
    sudo make -j5 uImage
    sudo mv /boot/uImage /boot/uImage_backup
    sudo cp arch/arm/boot/uImage /boot/
    sudo reboot
    modprobe cdc_acm
    sudo vim /etc/modules
    add "cdc_acm" no quotes.
    sudo usermod -a -G dialout ubuntu
    logout and back in

Share This Page