Lpc2000

At 09:47 PM 4/28/05 +0000, jase_ko wrote:
>--- In lpc2000@yahoogroups.com, Robert Adsett <subscriptions@a...>
>wrote:
> > At 04:36 AM 4/28/05 +0000, jase_ko wrote:
> > >I'm new at this. Can someone tell me the best way to measure the
>time
> > >between external interrupt calls?
> > >just point me in the right direction as to what to use..
> > >thanks!
> >
> > It depends on what you are trying to do, your question is a little
> > general.  Usually I just toggle an external pin and measure the
>result on a
> > 'scope.
>well i have calls to an external interrupt method every time a pin
>is grounded.. This happens extremely quickly and i need an accurate
>way of measuring the time between the successive calls of this same
>method. I'm using an LPC2129

In that case I'd definitely lean towards toggling an external pin.  That'll 
get you a number of useful pieces of information with two channels on a 
decent DSO.  Latency from pin going low to entering your procedure, length 
of your procedure, time between successive interrupts etc...  A decent DSO 
will have an envelope function and allow you to get a reasonable estimate 
of minimums and tell if you've missed any events.

Maximum information with minimal effort.

Robert

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