> On 2003.02.21 23:05 ragge@ludd.luth.se wrote:
> 
> > > What is this "ISP ERR"? 
> > That means that the interrupt stack is invalid, så there is nothing
> > the machine can do about it than to halt. It cannot give an interrupt
> > because it cannot save the current status and PC etc.
> OK, nothing wrong with my hardware. I hope this bug (?) is not related
> to my RX02 driver. ;-)
> 
It's usually not the hardware, it's something that overflows the 
interrupt stack, linke an interrupt routine that does something
bad or so :-)

> > It's usually simple to see what has gone wrong when this occurs; you
> > end up at the >>> and everything is available from there.
> Any hints on what to do to investigate this closer? 
> 
You have to hexdump the stack and match the stackframes against the call
frames manually. Boring but not especially difficult, I do it all the
time :-) Like this:

>>>E/G E
(gives something like 801FFFFC)
>>>E/V 80200000		! check the next longword

>>>E			! dump a bunch of the words. 

Then look at the calls frames that you see and check where they
are called from. Simple, eh? :-)

-- Ragge