I have seen documentation of three commercial Z8000 systems; the
Olivetti M20, the Zilog system 8000 (I think that was its name), and the
Ithica DPS-8000
==
Central Data in Champaign/Ubana made a Multibus Z8K board that they sold
with their OS and Xenix.
I'll get the docs up on bitsavers for it eventually. I also have some stuff
for the Zilog S8000