I think the PDP11-on-a-chip was post 11/23 (late '70s or early '80s) and was called the T11 or Falcon. With my mind's eye, I can see the blue A4 manual (I may even have a copy somewhere!) I think it took a leaf from the 68000/68008 in that it could drive an 16/8 bit bus. Now if this had been done a lot earlier, and RT11 was offered at a cheap price on it, how much of the market would CPM86 and MSDOS have had?
Regards, Graham Reid