Lpc2000

--- In lpc2000@yahoogroups.com, "Paul Curtis" <plc@...> wrote:
>
> I thought this witch hunt was over, but I see it's alive again. 
> 
...
> They might not wish to air this in public.  

It is there, Paul. 
And they might not want to air it.

> How about trying to find an

> instruction set definition of ARM on the ARM site?

Well, that could cut in "the other revenues", perhaps?:-)
Wanna get 13 MB pdf of ARM ARM, *free*? 
Let me know.

 
> > A search on "spurious" at the ARM web site yields 11 hits but 
> > these appear not relevant to the VIC and spurious interrupt 
> > problem with the ARM design that you seem to allude us to.
> 
> The web is an unreliable research tool.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
But it is nearly instant. :-)
I would not jump to conclusions about reliability, yet. 
It is a pilot's error...it is there (www.arm.com), I found it in 5
seconds. 
Strike one.
 
> > I also did a brief search for information on the web relating 
> > to spurious interrupts, and all the examples seem to point to 
> > LPC one way or another.
> 
> See what I mean?

Strike two.

BS. 
It is well documented, comparing with the "other stuff".
Start with this forum, please. 

When you learn a new word, isn't amazing how "suddenly" the new word
jumps at you everywhere you go? 


> 
> > A spurious interrupt is a hardware interrupt which is 
> > generated by system errors 
> > (http://www.answers.com/topic/interrupt-1), and systems with 
> > spurious interrupts in general do not meet compliance requirements.

So? 
What's your point? 
BTW, answers.com is not an authority on ARM.
Strike three.
You are out.
;-)
 
> Ok, so there exists at least one definition on at least one page of at
> least one web site that matches with your requirement of what "spurious
> interrupt" means.  In the case cited by Philips, the spurious interrupt
> does not stem from system errors, there is a specific issue in the
> ARM7TDMI-S which has been given the nomenclature "spurious interrupt"
> for want of a better name.

Yes. It is ARM7 "feature" for which three (3) solutions exist. 

[deleted]
> 
> > 2/  Can you tell us if there are any other ARM cores with VIC 
> > that also suffer from spurious interrupts problem that the 
> > LPC suffers from?
> 
> Why should Robert do your research on other processors?

Beats me. 
Why?

Jay, I think more fun would be to kick down a row
of parked "hogs" in front of some biker's bar. 
Try it -- once -- please.
;-)

> 
> It is not just the VIC.  The AT91SAM7 suffers the same with the AIC and
> the MAC7100 with the INTC.
> 
> Don't believe me?  I wouldn't:
> 
> http://www.freescale.com/files/32bit/doc/app_note/AN2891.pdf
> 
> http://www.atmel.com/dyn/resources/prod_documents/DOC1156.PDF
>

Good man! It confirms that it is ARM7 core 'issue'. 

> > PS:  I realise there has been discussion previously on 
> > spurious interrupts, but none seem to throw any light on 
> > whether this is a problem specific to LPC or it has to do 
> > with with ARM VIC design itself.
> 
> Who cares?  The issue is well understood and the workaround easy.

Case closed? 
Closed.

Roger


> 
> --
> Paul Curtis, Rowley Associates Ltd   http://www.rowley.co.uk 
> CrossWorks for MSP430, ARM, AVR and now MAXQ processors
>