I want to see phone number from gsm 900A shield sim card in 204 LCD display.. & with the help of 44 keypad i want to change the sim number location address.. When m press a key the location address increase & automatically the number will be changed & when m press other key the location address decrease & number will be changed automatically.. Plzz help me out.. I dont know how to solve this problem 
.. Plzz help me if possible.. Code plzz...