CC1110Fx / CC1111Fx
7.5 and 7.6 for characteristics of these
oscillators.
The low power RC oscillator calibration may
take up to 2 ms to complete. The ongoing
calibration must be completed before entering
PM1, PM2, PM3 or changing back to HS
RCOSC as clock source. It should be noted
that it is the initial calibration that uses 2 ms to
complete (the first 2 ms after HS XOSC was
set as clock source). After this the calibration
will typically complete within 130 µs after PM
has been set or clock source changed, thus
PM or clock change will be delayed by
typically 130 µs.
The CLKCON.OSC32Kbit selects the source of
the 32 kHz clock. This bit must only be
changed while using the HS RCOSC as the
system clock source. When the high speed
crystal oscillator is selected and it is stable, i.e.
SLEEP.XOSC_STB=1, calibration of the low
power RC oscillator is continuously performed.
This calibration is only performed in active
mode and PM0. The result of the calibration is
a RC clock running at 32 – 36 kHz for CC1110Fx
and 32 kHz for CC1111Fx.
SWRS033E
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