Content originally posted in LPCWare by Lien.Nguyen on Tue Apr 03 19:43:52 MST 2012
Hi Wookjin,
In section 27.6.5 of UM10360, I saw a guide for calibration as below. Did you try to use it?
"A recommended method for determining the calibration value is to use the CLKOUT
feature to unintrusively observe the RTC oscillator frequency under the conditions it is to
be trimmed for, and calculating the number of clocks that will be seen before the time is off
by one second. That value is used to determine CALVAL.
If the RTC oscillator is trimmed externally, the same method of unintrusively observing the
RTC oscillator frequency may be helpful in that process."
Best Regards,
Lien