Lpc2000

The real question is why the rise time is so long. A typical HEDS
encoder sensor is in the 50 to 100ns rise and fall times.

regards,
Charles

--- In lpc2000@yahoogroups.com, Tom Walsh <tom@...> wrote:
>
> widescreen03608 wrote:
> 
> >Hi all,
> >
> >On the CAP0.3 input I have pulses from an encoder and I want detect
> >both edges and generate interrupts. The signal is filtered so the rise
> >and fall time are slow (don't know exactly how long, but surely within
> >1ms). Is it possible that no interrupt is generated on CAP0.3, because
> >the signal is to slow?
> >
> >I didn't found any datasheets from Philips which this is described.
> >
> >  
> >
> Aside from the datasheet thing, wouldn't it be possible to use a
schmidt 
> gate to drive the capture intput?  Or some op-amp crossing-detector
with 
> hysteresis?
> 
> Regards,
> 
> TomW
> 
> 
> 
> >Thanks for help
> >
> >
> >
> >
> >
> > 
> >Yahoo! Groups Links
> >
> >
> >
> > 
> >
> >
> >  
> >
> 
> 
> -- 
> Tom Walsh - WN3L - Embedded Systems Consultant
> http://openhardware.net, http://cyberiansoftware.com
> "Windows? No thanks, I have work to do..."
> ----------------------------------------------------
>