Experimental Physics and
Industrial Control System

"Peregrine M. McGehee" <[email protected]> · Fri, 13 Mar 1998 10:41:56 -0000

Aloha,
	We (Deb Kerstiens and myself) have been investigating several solutions
for implementing logic chains under EPICS. The desired features include:
	o flexibility
	o ability to reconfigure without IOC reboot
	o maintainability 
	o readability of rules source
	o speed of execution

	After examining the present state of affairs - the CALC record, the PAL
record, SNL and so on - we have hit upon the following:

	We propose to modify the existing GENSUB record (a Gemini enhancement of
the SUBROUTINE record with multiple outputs and user definable input and
output data types) by allowing the SNAM field to reference an object module
_located on the host workstation_ and by adding special processing that
downloads the named object module into the IOC.

	This fulfills most of our requirements - with the possible exception of
'readability of rules source'. Although that can be solved with a suitable
preprocessor.

Peregrine

Peregrine M. McGehee		Project Engineer: LEDA Control System
(505) 667-3273			[email protected]	
LANSCE-8 Controls & Automation	Los Alamos National Laboratory

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System