[755-1] Parity

[Konstantinos Dovrolis <dovrolis@cs.wisc.edu>]

A couple of people asked clarifications on the Check
bit:

This bit should be generated as the even parity
of the 12-bit packet. In other words, with this
bit correctly set, the total number of ones in
the packet should be an even number.

Example:

11 01 00 0 1 0110   : correct packet

01 01 10 1 0 0111   : corrupted packet