Can someone help me out here?
i'm trying to write a program on 8051 assembly, my topic is a digital time zone clock with 7segment segment display with a 4x4 keypad , were each key if the time of one country. and i can't attribute the time to keys.
thanks for your help

This is not simple. First how is the keypad and display connected to the 8051 - via uarts, or other I/O? If direct I/O to the 8051, which pins are involved with each? Do you know how to read the pins (set/read registers, etc)? Have you written out the pseudo-code to do all of that? What about timing issues?

So, don't expect us to do your work for you. Write out the pseudo-code first, and then write the require assembler code. At that point, we may be able to help you sort out the problems.