Teensy 2.0 USB Problems

A few problems I came across playing around with my new Teensy development board. Decided to make a quick post on some solutions I found. Enjoy :)

Problem #1

Teensy USB device wasn’t being recognized. You can see the list of registred devices on Ubuntu using lsusb


Loaded program code may interfere with the USB registration process. Use the RESET button then check the output of lsusb again make sure the device is being recgonized. NOTE: you may have to hold it down and plug the USB device in then release it.

Problem #2

If that wasn’t enough my USB device was being registered under /dev/hidraw0 which isn’t recognized by the Teensy Loader Application. It only looks at /dev/ttyACM0


When the kernel registers the USB device it doesn’t give regular users write/read access to the device. You will need to setup appropriate udev rules to do this. udev rules are available from the Teensy website http://www.pjrc.com/teensy/49-teensy.rules you will need to download this file and place it in /etc/udev/rules.d/