I have four custom K60 designs where I need to switch to the RTC as my main input clock relatively early in the boot process.
Currently I attempt to switch, and then monitor the loss of clock bit. If it goes high I clear it and retry.
For the first time that both prime and battery power are applied, the K60 can never seem to successfully switch to the RTC. After prime power is cycled, and battery remains, the switch occurs without any problems.
What is the reason why the clock monitor has issues with the RTC the first power on?