I guess you mean you will use 12 pins as outputs (channels) and 1 interrupt pin that receives the IR codes. The remaining 2 pins could be used for 2 signalling LEDs.
Well, he has changed his post after my reply (post #2). As far as I recall it was a request to copy the codes from a microcontroller present on a IR kit of a well known company (also to modify it for 12 channel).
It is an old post.
Anyway, KerimF has given a good outline for the project.