Quote Originally Posted by BobP View Post
Hi xnihilo,

Don't get upset! We are only trying to help.

A lot of posts the user just wants the answer without learning the ways of Microchip and the PIC's. They learn how to solve that problem but not how to understand the datasheet.
Don't get me wrong, I have spent hours pulling out my hair and after posting the problem it turns out to be a simple mistake that I have made. We are all human.

The important part of the datasheet is this bit,

'For enabled interrupt-on-change pins, the values are
compared with the old value latched on the last read of
PORTA. The ‘mismatch’ outputs of the last read are
OR’d together to set the PORTA Change Interrupt Flag
bit (RAIF) in the INTCON register (Register 2-3).'

The following tip is the last I can give. The next step is to write the program for you!

Read the port before enabling the interupt!!!

Regards,
Bob
Come on! I know i sound stupid but i am not.
i DO read porta bits individually prior to enabling intcon, even if i maybe didn't mention it.
the int occurs anyway. when i outout the state of porta at the begining of interrupt routine 2 strange things can be noticed. it seems it is ra3 that triggers the interrupt. however i used the same program structure for another project and i didn'have such problem. even if the ra3 was left floating.
second thing: porta.5 value is not what it is supposed to be. with no wpu and set low with trisa, it is high when interrupt occurs. dammit.

the complete source code is at:
http://users.edpnet.be/charlesetchri...g/se210308.pbp