Experimental Physics and
Industrial Control System

"Jeff Hill" <[email protected]> · Wed, 9 Feb 2005 10:34:26 -0700

> -----Original Message-----
> From: Ralph Lange [mailto:[email protected]]
> 
> is that true for all target architectures or just for
> the PPC arch that
> Dirk is seeing this on?
> 

The WRS warnings concerning this issue are in an
architecture independent section of the documentation,
and I don't see anything specific on this issue in the
PPC specific section of the vxWorks 5.4 documentation.

A potential pitfall might be that the PPC compiler used
the FP registers to pass integer parameters, and that
the user's ISR didn't anticipate that scenario.

Jeff

> 
> 
> Jeff Hill wrote:
> 
> >Dirk,
> >
> >I don't know if anyone has made this suggestion, but
> >watch out for a driver that uses floating point in
> its
> >interrupt service routines as, on vxWorks, the FP
> >register contents are not saved / restored when
> entering
> >/ exiting interrupt context. The driver must do this
> >manually if it finds a need to use FP in its ISR.
> >
> >Jeff
> >
> >

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System