hi,

interfacing is related to hardware not to 'C'. for interfacing you must have good knowledge of digital electronics microcomputers, and peripherals u are interfacing with. you didn,t mentioned here whether you want to interface with pc or you are going for embedded controllers. if its with PC study about bus standards like ISA/VESA/PCI. some times parallel ports will do. may things involved here. start from the where you are up to.


abhishek