i have tried this but the assemblers give errror for this command..

i don;t understand one thing... i have used the same intercom for my experiments before but now i have purchased a new one as the older one had some problems ..but the new intercom ssytem does not respond to the same high low states as it was doing when i was using the previous intercom system...

to make it more clear its like:

u brought a PANASONIC 3+8 PABX and studied its hardware and finally you got to a point where u know how to deal with its hardware using your own controller program ...let say at P2.0 off hook is detected in this system at a High Signal.

Now you started doing experiments with this and some how this systems got some problems so you went to buy another system of same company and of same confirguration..but now the commands of off hook detection now working..y?