Jinx,

On Thu, 15 Sep 2005 00:30:41 +1200, Jinx wrote:

> > That may be true, but don't forget that  RETFIE  does it for
> > you anyway (that being its /raison d'etre/ - otherwise it's the
> > same as  RETURN)  :-)
> 
> At that point in Sean's code the interrupts hadn't yet been
> enabled Mr W, so reaching the RETFIE would be a tad on
> the difficult side ;-)

But we were talking about re-enabling it at the end of the ISR (where setting it explicitly, as Sean was 
doing, is unneeded if you're using RETFIE).  The fact that you can't get into the ISR unless it's enabled 
initially is equally (ir)relevant  whether you set it or the RETFIE does!
 
> I've made occassional use of the difference between RETURN
> and RETFIE. GIE is turned off by the interrupt process and if
> you end the ISR with RETURN, it stays off. This prevents any
> subsequent event entering the ISR until code turns GIE back on

Oh yes, but *usually* you want it set back on at the end of the ISR(s).

Cheers,


Howard Winter
St.Albans, England


-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist