I am working on a project using ATMEGA644 DIP. In this I have written a program for LCD interface which is working fine in Proteus simulation, but on the hardware it is not giving me any response on LCD. As I observed may be my micro controller is not set on the external clock or it can be any other issue also, same program is working fine with ATMEGA32 with 16 Mhz external oscillator. Please help me out. Thanks in advance.