Hi all
I want to make a program that in it :

user run the program and this waiting for call
when remote user call to a number , program can recognize it and after welcom to remote user , get a CODE number from remote user and if can locate CODE , it say a related message to remotle user.
I want to know can i make this program only with a MODEM hardware? or i need to a different and special hardware?

Thanks for your reply and excuse me for my english !