Detailed analysis of timer 0

Projects Programming
1

After working with timers for a bit I started wondering what the difference was between PWM, Fast PWM, CTC and other timer modes.

So with a couple of hours work testing the various modes with the logic analyzer, I present the findings below:

For example:

Phase-correct PWM:

870×304 47.8 KB

Fast PWM:

774×304 49.6 KB

The differences between "phase correct" and "fast" are:

  • Phase correct has the cycles centered in the period, whereas with fast mode the edges line up
  • Fast mode operates at twice the frequency (hence it's faster)

See the page mentioned above for example code, and screenshots of other modes.

2

Very nice... found those tables you've come up with very helpful... Amtel's datasheet does seem to be at its cryptic best in this section :slight_smile:

As a point of interest, one of the practical uses i made once of the signal detection capabilities you've outlined is to detect IR signals of 78khz range from a photodiode+comparator (found in some Aircon remote controls) when I wasn't able to find one of those TSOP1738 type detector ICs for the high freq range.