Hey people,
Just to announce that I've found a problem and solved it (at least it
is working last half an hour, before it needed a few seconds to crash)!
After disabling a lot of code I located the problem at interrupt
routines for timer and UART. I am using global shared variables to
measure time or to check rx buffer taken. I knew that changing that
vars isn't atomic function and that I need to disable interrupts when
working on them but I didn't take care about pipelining issue. Now,
these variables are operated within safe 'Supervisor mode' software
interrupts . And everything seems to be working fine.

I suppose this still makes me a newbie but hope I will soon be in
position to give help on this forum...

Thank you all for your support!

Aleksandar Start a New Thread