Enabling and disabling core clocks negatively affects the standard deviation of the HRCAP submodule. Do not enable or disable core clocks while taking measurements.
TSCTR is not writable; however, TSCTR can be
reset using ECCTL2[CTRFILTRESET]
Input synchronization is not applicable when
using the HRCAP enhancements, because the HRCAP
submodule is asynchronous to SYSCLK.
The Event Filter functionality is not applicable for HRCAP, which defeats the purpose of HRCAP as the Event Filter’s output is synchronous to SYSCLK.
The best practice is to use absolute time mode
for high-resolution mode. If time difference mode
is used, it can lead to inaccurate results if the
fractional value is not taken into consideration
for capture events that have reset the time base
counter.
Actual Capture Value = (Capture Value) –
(fractional value of reference event that reset
the counter)
For high-frequency input signals, the CPU can not
be able to cope with the speed of the captures. In
such a case, one-shot mode is recommended. This
mode allows the device to capture up to four edges
before waiting to be serviced when the CPU is
ready. This is applicable for the eCAP as well;
however, in that case the event filter can be used
to reduce the rate of captures.