Padu wrote:

>> Does the voltage drop similarly if you connect a 3M or 4M resistor to the
>> receiver output? If not, connect Vdd through a 1k resistor to RC2 and
>> measure the voltage across the resistor. Should be less than 1 mV.
> 
> The interesting point is that if I pullup RC2 with a 10K it (measuring the 
> pwm) works. 

Harold is probably right; looks like an output with a very weak pull-up (or
without a regular pull-up, and the pull-up you're seeing is just a side
effect). 

> but I was wondering what I'm trying to do is something pretty common no?
> How people usually connect a pwm source to be captured by the ccp
> module? 

This doesn't look like a problem with the CCP module; it looks like a
problem with the output. The CCP capture inputs are just normal
Schmitt-Trigger inputs, with a leakage current <1 uA. In principle, with a
normal push/pull output, "people" <g> do exactly what you did: connect it
to the capture input. It's just that it seems your output has a problem or
is not really a push/pull output and needs an external pull-up.

Any chance you can look at the output circuit? That probably would answer
your questions.

Gerhard

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