\chapter{Conclusion}

     An input-output system for connecting the CAM-8 cellular automata
machine to a host Sun Sparcstation has been designed.  This system 
provides for the downloading of data and control information from 
the Sparcstation memory to CAM-8.  It also allows for the transfer of
CAM-8 status information in the opposite direction. The input-output system
is still
in the process of being thoroughly simulated and built. 

     Some of the 
input-output circuitry of the controller chip described in this document may be amended as certain
features of the CAM-8 I/O are dropped or added.  It is hoped that a
preliminary version of the controller chip will be fabricated by August 1990.
At that time, a simple two module CAM-8 machine will be built and tested.
Real cellular automata experiments will be run on the system to determine
whether the goals of the initial design have indeed been met.

     A special version of the interface board described in this thesis will
be wired up to exercise the SBus protocol and to gather certain statistical
information on the operation of the SBus.  This should aid in any last minute
modifications to the interface board hardware.  It will also help to direct
the development of software for the CAM-8 system.  

    An attempt will be made to try to integrate the logic for the interface
board on the controller chip itself, in parallel with its programmable
logic implementation.  Selector pins on the chip will allow it
to function as a CAM controller chip; an interface board controller chip;
an interface board control registers chip; or an interface board data registers
chip.  Successful implementation of this logic on the gate array will easily
meet all SBus electrical, timing and size requirements for the interface board.
The reader may recall that this was one of the major problems with
implementing the interface board in programmable logic.  The author is 
presently conducting active work in this area.

    Printed circuit boards to house the entire CAM-8 system still have to
be fabricated.  The high speeds of system operation mean that simple wire
wrapped test boards will probably not function properly.  Thus printed
circuit technology is needed even for the preliminary test versions.

     Once a two module CAM-8 machine has been built and tested, larger 
machines will be developed.  However, the input-output system should 
remain the same
for these bigger machines.  As the CAMs grow in size, the
depth of the PBus will grow accordingly.  This would require that 
PBus nodes be physically built into the system.  Future CAMs may include second or 
third generation versions of the CAM-8 controller chip with added features.
It is hoped that the CAM-8 machine can one day be industrially
manufactured and distributed to scientists around the world.  As a scientific
tool, CAM-8 will allow physicists to run cellular automata experiments to 
model very large universes of cells.  Such experiments can ultimately lead
to a better understanding of many statistical phenomena of physics and matter.

     It is the author's hope that this thesis forms an
integral part of the final working version of the CAM-8 cellular automata 
machine and be useful in 
research on other machines with similar architectures as well.

