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<== Date ==> <== Thread ==>

Subject: Re: Hardware Configuration
From: Andrew Johnson <[email protected]>
To: [email protected]
Date: Fri, 22 Nov 1996 13:07:26 +0000 (GMT)
Chip is right in rejecting the idea of having a single h/w config record
per signal, and possible ever per I/O card/module is too much. Marty's
record defines setups for a whole field-bus, which is a reasonable level
of overhead.  For CANbus I give this sort of data to an initialisation
routine in the startup script, but there are reasons why some sites don't
want to do this. 

I like the idea of being able to define a record type which doesn't
support the whole of dbCommon. In fact I wonder whether we could make some
fields optional by putting them in a sub-structure (say one for CA monitor
fields, another for scan fields etc).  Why should *every* record type have
to support ASGs, Scan types, Disabling, Channel Access monitors, Alarms
and Forward Links?  Most will, but I can forsee simplified record types
for which some of these aren't necessary. 

For example, a common use for an AO record is to get a value from
somewhere and put it elsewhere. This doesn't need alarms or monitors
necessarily, so there could be a simple "copy" record which just does this
job.  It ought to be possible to maintain backwards compatibility while
adding features to support these simplified record types, and Hardware
Configuration records have similar kinds of characteristics.

- Andrew

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References:
Re: Hardware Configuration watson

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