I'm looking at doing something that overlaps with what TelephoneBill did over here: https://forum.pjrc.com/threads/30822-Teensy-3-1-and-Flextimer(s)-Counting-external-pulses-accurately in that I need to count external pulses.
As it happens, in my case the average rate is low, but they could arrive in rapid succession, hence the interest in using direct external clocking of a FlexTimer counter, which TeleponeBill describes.
But that raises a related puzzle: How to start a FlexTimer counter from an external wire?
Looking at the ARM docs:
... I see how use a program to set the Flextimer counter to a value (for example zero), and to enable and disable counting. But I'm not seeing a way for an external input pin to control those functions to trigger the start of counting.
Of course, an input pin could be polled or could trigger an interrupt, and that code could enable the counter. But I'm wondering if there's a lower latency approach.
Graham
As it happens, in my case the average rate is low, but they could arrive in rapid succession, hence the interest in using direct external clocking of a FlexTimer counter, which TeleponeBill describes.
But that raises a related puzzle: How to start a FlexTimer counter from an external wire?
Looking at the ARM docs:
... I see how use a program to set the Flextimer counter to a value (for example zero), and to enable and disable counting. But I'm not seeing a way for an external input pin to control those functions to trigger the start of counting.
Of course, an input pin could be polled or could trigger an interrupt, and that code could enable the counter. But I'm wondering if there's a lower latency approach.
Graham