I was getting strange behaviour using USB_CDC_ADM on Ubuntu 13.10
It appeared to be dropping characters and garbling input; for instance when I ran example_usb_com, and pressed ‘t’ repeatedly I got this:
However after a minute or so it subsided and the app worked normally. This kind of thing happened with other apps using the USB serial too.
WELL, it turns out that Ubuntu’s Modem Manager is opening the USB device and trying to interrogate it with commands like “AT+GAP” (as discussed here). Eventualy it gives up and the serial device stops acting up. To fix it, I edited the file /etc/udev/rules.d/99-pololu.rules that ships with the SDK and changed the line from
then ran sudo udevadm control --reload-rules. Now the USB device works correctly straight away. Hope this helps someone!