USART interrupt seams to be good. But as far i can understand HSEROUT/HSERIN dont accpet inverted mode. And to get correct data out of HSEROUT/IN i need RS-232 controller like MAX232 ic right?

So best solution for me would be a inverted SEROUT/SERIN interrupt, but is that possible?
I have played little with "Darrel Taylor instant interrupts" and interrupts seams to be a very useful in many situations!