Quote Originally Posted by flotulopex View Post
Nevertheless, I have my PIC running for more than an hour now and it often hangs (= time is no incrementing every second anymore) and starts overs maybe 10 or 20 seconds later.
That sounds more like a USART buffer overflow.
If it isn't cleared ... it will hang.

Try adding ...

DEFINE HSER_CLROERR 1 ' clear overflow automatically