Hi: IEEE Spectrum has a nice article "Re-creating the First Flip-Flop”, sub-titled "The fundamental building block of modern digital design turns 100”. See https://spectrum.ieee.org/geek-life/hands-on/recreating-the-first-flipflop Cheers Brian Randell — School of Computing Science, Newcastle University, Newcastle upon Tyne, NE1 7RU EMAIL = Brian.Randell@ncl.ac.uk<mailto:Brian.Randell@ncl.ac.uk> PHONE = +44 191 208 7923 URL = http://www.ncl.ac.uk/computing/people/profile/brianrandell.html