Hi Nyhayu!
What in your opinion is the diffrence between "real value" and "hex value"? Hex value isn't real? What are you asking about? Is your question : how to change hex value to its decimal representation?
You can be sure : HEX VALUE is only the method of storing numbers and THIS IS TRUE. But the other thing is how to change it to the decimal value and you can find a lot of methods here. If you have some troubles, write to me. I will send you an assembler routine and you can learn using it. Or - download Raisonance C compiler from its web site and write the routine (or whole code) using C. It is very easy in C :o) Using demo version of Raisonance C you can write up to 2kB of code.

Good luck!
Jacek