Lpc2000

--- In lpc2000@yahoogroups.com, "relentless_6995" <bobd@...> wrote:
>
> Well as the original poster I have some more news - the WDT does 
> fire off a reset while the code is buried in an IRQ. For yet 
> unexplained reasons the WDT that I had working appeared to no longer 
> be getting activated. I took the few lines of code involved apart 
> put them back together and walla it began working again - but I'm 
> suspicious - best I can tell I have the exact same code again and 
> now it works. It's like the WDT got jammed up into some mode where I 
> couldn't start it (as whacked as that sounds)??
> 
> With WDT working again, I proceeded to purposely cause the DATA 
> ABORT IRQ where the code gets trapped in an endless loop and indeed 
> the WDT RESET does go off to start app over again. So that is the 
> good news.

Thank you for the update.  Please feel free to keep us informed.

I am looking at (and documenting) at a very similar problem relating
to WD timer not initiating a reset all the time.  It seems to fit your
description.  Which LPC variant are you using?

The problem they were having is that on LPC2294 their WD recovery did
not work reliably.

I asked them to validate the recovery code.  They were able to show
that synchronous jumps to it always worked, but when the jump was
asynchronous the recovery failed 10 percent of the time under certain
conditions.  The symtoms are as if the processor locked up.

As they needed WD only during development stage, I got them to work
around the problem quite easily.

However I am interested in repeating this problem so that someone else
might benefit from more information about this problem that you seem
to have also encountered.

I will post details of this problem and the findings in my "LPC
problems and solutions page" when I find the time to verify a few
details myself.

Regards,

Jaya