PS:
> Not the simplest machine to implement, mind - the -8 is a lot
> simpler.
As a rough measure of how much more complex, the -8/E and -11/20 are roughly
contemporaneous, and built out of the same technology (SSI TTL on larger
boards): the -8/E CPU is 5 quad boards, and the -11/20 CPU is 9 quad board
(equivalents - some are duals, etc).
Noel