Sorry, I know that I am disturbing and u all must be thinking that my IQ have dropped to "0", but if ur not given the specific residence no. and location of the person u know then how could u find out instead given a geographical map of the city. Sorry once more but see to it if u all can help me, because I really need some, for which I will be very much obliged and ever grateful. Thank you.
"But I am worried about the fact that will a code written for AT89Cx051 work for AT89C51." I asked you before what you believe to be the important differences between these devices with regard to their ability to handle I2C interfacing. Why in the world would you be worried?