Im using emulator for quite a bit now and i would like to start one of my own, for sure as it is my first project i want to try on an old system like the master system,game gear or maybe even the atari or coleco
You do
not want to try to tackle the Atari (assuming you mean the 2600). It's hard enough just to program anything for it, let alone emulate it properly. In fact, the rest of those systems are all pretty similar. SMS and Game Gear are almost identical aside from how the palette is handled, and Colecovision uses the same CPU and a similar VDP. If you want a game that's really easy to emulate, Phoenix and Space Invaders seem to be best.
Im new to programming but i dont care putting alot of time working on this.
It's been said that you can't do an emu as your first programming project, but that's not true. If you've been into emulators long enough to remember ESNES, the author's page mentioned that it was his first real programming project.
That doesn't mean it will be easy, though. You've got a lot of stuff to learn:
1) General programming concepts: Programming is not intrinsically difficult, but it's difficult to really get things done without a good understanding of the methods available and strong problem-solving skills. A basic knowledge of algebra concepts (e.g. what you'd get from a decent pre-algebra class) would probably help too. You will have to learn at least one programming language. I suggest
learning C, as it is relatively portable, still enjoys popular use, and provides suitable mechanisms for writing emulators and similar low-level applications. In order to learn C, you'll also need a
C compiler, or else you'll be stuck once you want to test any code.
2)
Digital logic: This is the basis for all digital computers. You don't necessarily need to know much about it to be a programmer, but it's nice to know when writing an emulator. You don't necessarily need to go through all the stuff about the complex constructs like latches/flip-flops, but it's important to be familiar with all the logic operations.
3)
Assembly language programming and computer architecture: How computers are built and the programs that they actually run. Without an understanding of this information, you probably won't be writing an emulator, since an emulator has to reproduce the behavior of a computer. The book I've linked to is about the Intel 80x86 family specifically, but the basic concepts will translate to other processors. Specifically, Volumes 1 and 2 contain most of the general information that will be useful.
I'd like to provide you with some better resources, but I learned this stuff rather haphazardly over the course of some years, mostly running into bad texts. If you have any "stupid" questions, feel free to PM me.