Speaking of PDP-8s, and now PDP-10s - a thought that passed my mind: Is there a good reason why DEC did not use the PDP-8 architecture in the PDP-10, for proper channel controllers? Cheap, versatile, sixbit, and when the KA10 came out, already designed. I would have thought it to be an obvious "drop-in" solution. Any thoughts? William Donzelli aw288 at osfn.org