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PWM Input Capture - TIMx-CCMR1->IC1F filter on pulse width?

john doe
Lead
Posted on August 16, 2017 at 01:53

I'm not understanding proper use of TIMx_CCMR1->IC1F. Is it only for frequency?  I'm looking for a way to filter pulses out whose width is too short of duration.

1 REPLY 1
Posted on August 16, 2017 at 09:36

As the description says:

The digital filter is made of an event counter in which N consecutive events are needed to validate a transition on the output:

i.e. two consecutive transition (i.e. a pulse) closer together than N samples (see below)  are ignored.

The first part of first sentence of the description may have confused you, though:

This bit-field defines the frequency used to sample TI1 input and [...]

There are two choices of the sampling frequency: the internal input clock of the timer, fCK_INT, and a divided version of it, fDTS, see TIMx_CR1.CKD

JW