On the Teensy (I am using a Teensy 3.1)

This is a sample reworked for the Teensyduino HID RAW example for the Teensy 3.1.
The sample implements a HID RAW USB device on the Teensy 3.1 that sends a RAW 64 byte
packet every two seconds.  This packet contains in the fist byte 0xAB and in the 
second 0xCD; the next 24 bytes are analog mesurments from the Teensy, the rest of the 
bytes up to the last two bytes are zero.  The last two bytes are the number of packets 
sent.
 
The Teensy can also receive a 64 byte packet as well, in this example the first byte 
will set the outputs on pins 0 - 7.


The linux user code to interact with the Teensy.

The original code used libusb but for some reason only seven packets would be sent 
then it would fail.  This code is from Linus Torvalds' repository, using the hidraw 
device driver.  I modified the code to receive the packets from the Teensy and display
them to the console.  I have not yet added the send packet that was in to original client
example. I will eventually add this code as well.


No udev rules as yet so you must run as root.