Re: devLib, locationProbe routine

[mrk@aps.anl.gov (Marty Kraimer)]

> From anj@mail.ast.cam.ac.uk Wed Oct 26 08:21 CDT 1994
> Date: Wed, 26 Oct 1994 13:19:11 BST
> From: Andrew Johnson <anj@mail.ast.cam.ac.uk>
> Subject: devLib, locationProbe routine
> To: EPICS Technical list <tech-talk@aps.anl.gov>
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> Am I right in thinking that the routine  locationProbe  in devlib returns 
> SUCCESS to indicate that the given address does *not* respond to VME accesses of 
> any size?  I presume the aim here is to indicate that this area of the memory 
> map is currently not used.

No it returns success (0) only if something responds AND no one else has
requested something from the rage of addresses requested. Thus ALL non 0
returns values are errors. 
> 
> Should I be using this in my driver to check that a board is present?  The older 

Yes you should.

> drivers use vxMemProbe, which returns OK if something responds.  It seems wrong 
> to expect an error code (S_dev_addressOverlap) as the status return indicating 
> success (ie board found), which is what I would have to do if I used the  
> locationProbe  routine.
> 
> Are there plans to modify the existing drivers to use the devLib facilities?
> 

Yes but we have not yet got around to doing this. We (Jeff Hill mainly) added
these routines with the intention of converting all existing drivers/devsup
but have not found time. Until everything is converted location Probe has
limited usefullness.


Marty Kraimer