How 2 make my own PC gamepad/minikeyboard

[Byt3]

Hi there. I ever wondered how to completely build my own mini keyboard like this :
One day i found circuit created only with electronic logical gates (like AND, NAND and so on), which was used to obtain information about pressed buttons and transmitted it into the console (yeah, it was for PS). But now i want to build my own USB device for PC, but i dont have any idea, where I should start searching. So I'm here to ask you for advice.
Something about that: It will be 12-16 button device, connected to PC over USB and some software to assign any key or macro to every button.
So thats it and now comes your part. Can you help me with it? 

[Thargok]

You need to figure out how you want the switches to work.  Once you do that you need to figure out how you want it to register on the computer (actual keys or joystick buttons).  And there are tons of these things floating around all over the net.  And they aren't that expensive.

We don't build arcade controls because they are cheaper...but because they hold fidelity to the original products.  In all honesty just buy one, it will come with the software.  But if you are hell bent on it, I suggest you read up on making PCBs.  For input encoding I would probably use a GPWiz (I have one I float around for different projects, and have no complaints; although soldering to it is an act of patience and steady hand, but I have done it)

[Byt3]

Well, I'm a little newb in this. But I think it could be done very easily, coz a lot of cheap gamepads are connected via usb and they have their own software, with which u can assign any keyboard key or macro to any button on the gamepad. But i really dont wanna buy any of them, coz their PCBs are way too different from my mini keyboard idea. So can you explain me how to do it step by step?

[NinjaEpisode]

Well, I'm a little newb in this. But I think it could be done very easily, coz a lot of cheap gamepads are connected via usb and they have their own software, with which u can assign any keyboard key or macro to any button on the gamepad. But i really dont wanna buy any of them, coz their PCBs are way too different from my mini keyboard idea. So can you explain me how to do it step by step?

Take a USB keyboard and do a keyboard hack on it into the format/keys you want would be my only suggestion.

If you're actually looking to design a PCB, there are people who spend literally years in school to design a device such as you're describing.