Maintaining the precision of the 32kHz clock is on you allone.
Precision depends on
- Initial crystal precision
- Aging of the components
All these factors are not related to the PSoC
High precision clock crystals can be trimmed to 20ppm precision. Within 2 years = 2*365*24*60*60s = 63072000s you will have to expect a deviation of 63072000s*0,00002 = 1261,44s = 21minutes.
When you cannot live with that you will need to correct the clock by connecting to a radio-controlled clock module. Additionally you could consider using energy harvesting (Solar, piezo)).
in order to calculate exact time. I must know about code execution time, deep sleep time, active time during 1s.
I would suggest you to measure your program execution times yourself.
Thanks. I misunderstood sleep process will divided into some sections.
and fortunately clock is only affected by ppm.
Thanks for your help