s12p no dlycnt on input capture

sprince — Tue, 09 Feb 2010 07:58:35 GMT

Perhaps I am not reading the input capture section for the s12p correctly. I cannot find the delaycount register. Does it not exist on the p version? This makes no sense-how can noise be filtered out say, if one was to connect the input capture pin to a camshaft or crankshaft sensor? Even with external filtering on this pin I have always seen noise and used the delay count to filter it out. Wasn't this derivative designed specifically for the small engine market?

S. Prince

Re: s12p no dlycnt on input capture

isionous — Thu, 29 Oct 2020 09:22:46 GMT

sprince wrote: this makes no sense-how can noise be filtered out say, if one was to connect the input capture pin to a camshaft or crankshaft sensor?

You can still filter out noise via software. Use input capture to detect a rising edge and then check the pin a little bit after that to see if the pin is still high.

ECT_EnableInputCapture(0, RISING_EDGES);...void interrupt TC0Handler(void){    if(TC0IsInInputCaptureMode()){        //switch to output compare mode to wait a while        TC0 = TCNT + SOME_DELAY;        ECT_EnableOutputCompare(0);    }    else{        if(PTT_PTT0){ //if pin still high            PulseCount++; //got true pulse, not noise        }        //switch back to input capture to detect rising edges        ECT_EnableInputCapture(0, RISING_EDGES);    }}

Or something like that.

topic Re: s12p no dlycnt on input capture in S12 / MagniV Microcontrollers

s12p no dlycnt on input capture

Re: s12p no dlycnt on input capture