OK guys,
I really gave up, ya i can understand that after working with this software thing , multitasking etc.. i have learned many things like driving 7-segment with refreshing methods using transistors only, made a some what working clock, then also made a PIR sensor door look etc.. but still this pabx and pulse dialing stuff is way over my head...

is it possible that some how if we can make such software which can be placed here on this website for 8 lines intercom system so that other people will not have much trouble in understanding the software...

its really diffcult like studying controller and its related projects is one thing and pbx software is out this world thing.

lets not make pbx software only make a sofware which works for 2 lines using MT8816 , Pulse Dialing..

i have completed the work or you can say by doing reverse engineering copied it from a Market product..i will place the entire info here and then some one can help me out on the software part...