How long does PULSIN wait for a pulse?

[Byte_Butcher]

I just know this has been covered before. Or maybe not because the answer is too obvious and I'm just too blind to see...

The manual states:
" The measured width is placed in Var. If the pulse edge never happens or the width of the pulse is too great to measure, Var is set to zero. "

So how long is "never happens" or "too great to measure"?

When I use PULSIN inside a loop to look for an IR signal it really slows things WAY down.... :(

Thanks

steve

[rmteo]

The resolution of PULSIN is dependent upon the oscillator frequency. If
a 4MHz oscillator is used, the pulse width is returned in 10us increments.
If a 20MHz oscillator is used, the pulse width will have a 2us resolution.
Defining an OSC value has no effect on PULSIN. The resolution always
changes with the actual oscillator speed.
PULSIN normally waits a maximum of 65535 counts before it determines
there is no pulse.

With a 4MHz clock that works out to be 655mS (or 131mS at 20MHz).

[dhouston]

DEFINE PULSEIN_MAX counts will specify the time to wait.

[Byte_Butcher]

PULSIN normally waits a maximum of 65535 counts before it determines
there is no pulse.


Thanks rmteo,
I kind of guessed that from the length of time it took, but I didn't find it in my search. The "help" file in MCS didn't really go there.

Dave,
Bingo!
"DEFINE PULSEIN_MAX counts" is exactly what I needed. I only need to look for 500 counts, so 65K+ was a bit much.

The DEFINE sped my loop up a LOT and works great. A bit embarrassed I didn't find it on my own. Thanks to both you guys for pulling the blindfold off . :o :)

steve