Hi, Sarma

Seems migrating from C54' to F84' is not so easy ...

first, have a look to Appendix C from 16F84 Datasheet : main explanations are here.

BUT ... if the programmer has used its own tricks ... that can be a bit harder !!!

I experience it on another clock program ( DCF Berliner Clock ) ... "basic" clock works well, but I still can't get the LED multiplexing work properly ...

it relates to Writing to the PC ... but where ???

good luck

Alain