Experimental Physics and
Industrial Control System

Heinrich du Toit <[email protected]> · Thu, 27 Sep 2007 13:44:47 +0200

Ok sure.

But do you code different for number 2 than number 1?

Because in the AppDevGuide it says that everything should use CA to
access PVs and not DBaccess as described in Ch 15.

So my question is that if I run CA code inside the IOC does that somehow
bypass some networking code ect to that it directly access the PV inside
the same IOC - as if I would be working directly with DBaccess code
(ch15)

Or do I need to use DB* code? 

On Thu, 2007-09-27 at 13:25 +0200, Gasper Jansa wrote:
> Hi
> 
> Hm, maybe I misunderstand you.
> 
> What exactly  did you mean by "running CA inside and IOC"?
> 
> If you wrote a CA client which is not a part of the IOC application then 
> of course  all communication goes via CA.
> 
> If you have some C code inside IOC application then you can get PVs via  
> database calls which are explained in AppDevGuide.
> 
> Best Regards
> Gasper
> 
> 
> Heinrich du Toit wrote:
> > Hi
> >
> > Thankyou very much for your help.
> >
> > so why do I still need to call ca_flush_io all the time?
> >
> >
> >
> > On Thu, 2007-09-27 at 12:48 +0200, Gasper Jansa wrote:
> >   
> >> Hi
> >>
> >> By default all PVs inside the same ioc connect to PV in the same IOC 
> >> directly.
> >>
> >> You can however force link to go via CA stack. 
> >>
> >> You can find more about links on chapter 5 in AppDevGuide.
> >>
> >> Best Regards
> >> Gasper
> >>
> >> Heinrich du Toit wrote:
> >>     
> >>> I just want to clarify something.
> >>>
> >>> If I run CA inside an IOC and connect to a PV inside the same IOC.
> >>> Does this in effect really bypass the CA networking part and uses direct
> >>> DB access to that PV since it's inside the same program?
> >>>
> >>> Or do you need to do something special to enable this optimization
> >>> thingy :)
> >>>
> >>> thanx
> >>> -Heinrich
> >>>
> >>>
> >>>   
> >>>       
> >
> >
> >   
> 

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System