On the Design of Display Processors
The flexibility and power needed in the data
channel for a computer display are considered. 
 To work efficiently, such a channel must have a sufficient number
of instructions that it is best understood 
as a small processor rather than a powerful channel.
 As it was found that successive improvements to 
the display processor design lie on a circular path, by
making improvements one can return to the original 
simple design plus one new general purpose computer for
each trip around.  The degree of physical separation 
between display and parent computer is a key factor in display processor design.
CACM June, 1968
Myer, T. H.
