[Xylo-SDR] LVDS stuff

[Philip Covington <p.covington@gmail.com>]

http://www.national.com/appinfo/lvds/

http://www.national.com/appinfo/lvds/0,1798,115,00.html#BLVDSIntro

http://www.national.com/AU/design/0,4706,0_61_,00.html

http://www.national.com/AU/design/1,4678,14_0_,00.html

73 de Pil N8VB