I am looking for advise on the best way to implement a software enabled one shot external trigger timer that is NON-retriggerable. So far I have devised a number of solutions but all seem to have a downside either in cpu cylces (software), number or timers required (complex) or external hardware and none of them feel like the elegant solution I was striving for.
Is there a way to do this with timers only? Not using interrupts or software other than to enable the trigger when needed?
Picture is worth a wall of text right?
Black is 1 MHz external input trigger
Green is rising edge trigger on 1 MHz input
Red is desired output pulse
note: moved to questions section as suggested