Huge thank you dear lar3ry. And thank you all of you guys. I am sorry for my stupidity but as I have said I am just the beginner.
Lar3ry I will try to add code you suggested and we will see if it works. But anyway I cant believe that this should be complicated like this. You see I am thinking simple: if I have time from RTC all the time so I should tell to program only to look at that time and when it will come to time I need it trigger something to do. But now from code you suggested I see that processor should count minutes since midnight and do something after pass minutes needed. Huh this is something. Anyway if it no more simple way I will try lar3ry code. Thank you again guys.