No.
Description
Timing
3
High → low:
Old clock
source
CKS1 and CKS0 are
rewritten while old clock
source is high and new
clock source is low.
New clock
source
*
FRC clock
pulse
N
N + 1
N + 2
FRC
CKS rewrite
4
High → high:
Old clock
source
CKS1 and CKS0 are
rewritten while both
clock sources are high.
New clock
source
FRC clock
pulse
FRC
N
N + 1
N + 2
CKS rewrite
Note: * The switching of clock sources is regarded as a falling edge that increments FRC.
189