Thanks Mr. Craig,Andy and michael.
My P89C51RD2 project controls Water pump,Home Security system .It is working
fine with keypad and LCD etc.The user interface consists of lighting controls,
T/V control, Heating and Air conditoning control, Telephone system etc.

I ve tried out the Tel dialer. It is OK. Now I am confused and wonders how to interact with uController to get the job done.The uController is already connected with MAX232.

Kind regards

Harnam