RTC via TMR0 + HSERIN and 16F916

[skimask]

AND you have to add the ON INTERRUPT latency

But in this case, latency shouldn't really matter, 'cause the interrupt stubs isn't going to take anywhere near the total period of the interrupt (well, shouldn't anyways), T0 isn't being stopped by anything...

And yes, DT's INTs and Elapsed Timer...always a good plan...

[boban]

Hello Skimask,
thanks a lot for your help, I see.
I am thinking that the easyest way to solve my problem is to use

OPTION_REG = $d5

disable
intManagement:
if (INTCON.2 == 1) then
ticks = ticks + 1 ' Count pieces of seconds
If ticks >= 61 Then
if (ACTIVITY_LED == 1) then
low ACTIVITY_LED
else
high ACTIVITY_LED
endif
ticks = 0 'One second elasped - update time
manageIntSecond = 1
endif
INTCON.2 = 0
endif
INTCON.7 = 1
resume

[skimask]

All other things being equal, that would give you roughly 49-50 seconds of slow error per day. Add one second every half hour, and you'll practically be dead on.