Experimental Physics and
Industrial Control System

"Jeff Hill" <[email protected]> · Mon, 17 Oct 2005 15:24:35 -0600

Another important benefit of the data access approach is that the property
set that is posted with the event by a service is loosely coupled with the
property set that is requested when a client subscribes for an event. The
client's set need only be a subset of the service's set. We can do this
because the purpose of the property (parameter) passed with the event is
known to the communication system. That is not the case with IDL based
systems like CORBA and ICE. This loose coupling is an important enabler for
a tool based approach. For example, LANSCE devices might include the "beam
flavor" property in the value change event, but MEDM isn't required to be
recompiled to conform to that interface. MEDM might however include a
configuration for an ASCII event filter in the future - something like how
color rules work today. At LANSCE that ASCII filter might select updates
only specifying a particular beam flavor.

Jeff
__________________________________________________________
Jeffrey O. Hill               Mail         [email protected]
LANL MS H820                  Voice        505 665 1831
Los Alamos NM 87545 USA       Fax          505 665 5107

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System