2.14 I2S

https://github.com/skristiansson/i2s/blob/master/rtl/verilog/i2s_rx.v

http://www.beyond-circuits.com/wordpress/tutorial/tutorial18/

http://www.beyond-circuits.com/wordpress/tutorial/tutorial18/part2/

http://www.beyond-circuits.com/wordpress/tutorial/tutorial18/part2/discussion/