Select the PLL to drive the Time Elapsed Counter
(TEC). The BAW APLL offers the highest accuracy time measurement due to the highest TEC
clock frequency, however, the conventional APLL (LC VCO) provides slightly longer
roll-over times.
The BAW APLL source is selected by
setting REF0_MISSCLK_VCOSEL to 0.
The conventional APLL source is
selected by setting REF0_MISSCLK_VCOSEL to 1.
Select GPIO or SPI chip select as a trigger to
capture the TEC counter value to TEC_CNTR field. Using a GPIO does not require any
special timing for the SPI SCS pin. Using the GPIO pin for other purposes is possible,
enable the TEC functionality when required.
GPIO trigger is selected by setting
TEC_CNTR_TRIG to 1.
SPI chip select trigger is selected
by setting TEC_CNTR_TRIG to 0.
Enable the TEC counter by setting TEC_CNTR_EN to
1.