RFreader reads the input fron the ID-card and sends it to microcontroller. mcu compares the same no with the available no's. If no. is matched then generates output pin high. Plz help in me in implementing the code in c.Total there are 250 different IDs available.
So get out your 'C' textbook, and look at what facilities the language provides for doing such things.
Hint: don't (just) think of it as a "number"; try thinking of it as a just a sequence of bytes in memory...
"giving some error"
What error, exactly, does "it" give?
What effort did you put into fixing the error?
Nobody can help you to fix the error when you don't say what the error is!
Debugging is an essential part of any development project - you're not going to get far if you just give up as soon as you get "some error"!