Experimental Physics and
Industrial Control System

[email protected] (Allan Honey) · Wed, 25 Nov 1998 16:41:35 -1000

> First off,  Happy Thanksgiving to my American collaborators and their
> families.
> 
> I want to have a record (or record-set) which emulates a set-reset latch.
> My application is to provide a 'processing-active' flag set while a group of
> record processing and sequences are active.
> 
> The BO record does this (latching function) from a medm page using dbPuts to
> the VAL field,  but I want the same effect based on database processing
> links.  That is,  an FLNK from record 'A' should set the latch (VAL =1),
> and an FLNK from record 'B' should reset the latch (VAL=0).
> 
> I feel like I can't see the forest thru the trees on this one.
> 
> 

I have placed two capfast drawings, that I use for this purpose, in
	ftp.keck.hawaii.edu
	cd pub/epics
	RSFF.sch and RSFFE.sch

RSFF.sch is an implementation of an RS flip-flop using two BO records
and two calc records

RSFFE.sch is similar but it uses 1 fanout record and two calc records such that 
the fanout record is used as an enable to cause the flip-flop to latch its 
inputs and set its outputs as appropriate.

Allan

Happy TG!

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System