nesdev.org

SNES emulators seem to be mostly in the dark ages for debuggers, there's nothing as powerful as FCEUXD for the SNES. NO$SNS looks okay, but it doesn't seem to have data breakpoints. I downloaded some emulator called "sleuth", and it has a debugger, but it didn't help. When I used it, it c...

The game depends on a (unfortunatly misnamed) flag called JoypadOverride (= $0758)

How do you know the flag's name that the programmers used?

Did anyone play these games (for the SNES) as a kid? (or maybe still once in a while when they were older?) Anyways, I fired it up the other day, and I started thinking about how the game actually works. For the uninformed, there are many teams, and many players on each team, each of whom has unique...

Galaga was originally an arcade game, but a NES port was eventually made. For those who don't know, it's basically an evolution of space invaders. Anyways, it impresses me for a NES game; I'm not sure how it does a few things (though some of these things that I wonder about aren't extant in only the...

NTSC and PAL are differing video formats, both in color encoding and frame rate. So they have two different NES consoles to handle this difference. It just happens that in many 50Hz mains countries, they use PAL, and in many 60Hz countries, they use NTSC (because originally the video standards were...

The power supply of an NES consists of a brick, a low-voltage cable, and a voltage regulator inside the Control Deck. Nothing after the regulator sees the mains frequencies. And strictly, "NTSC" and "PAL" are misnomers, as the NES sold in Brazil uses NTSC timing (because of 60 H...

The power supply of an NES consists of a brick, a low-voltage cable, and a voltage regulator inside the Control Deck. Nothing after the regulator sees the mains frequencies. And strictly, "NTSC" and "PAL" are misnomers, as the NES sold in Brazil uses NTSC timing (because of 60 H...

Yes. SMB1, for instance, has numerous changes from the NTSC version to the PAL version. Most Codemasters games and a few newer homebrew game, for instance, will automatically adjust these speeds based on the TV system. Thanks for the quick reply. May I also ask, what would happen if one hooked up a...

On an interesting note, in my sprite handling code, "state" is also used as the animation number. I grabbed that idea from Capcom. What do you mean by "animation number"? Also, thinking about NTSC and PAL, how would one convert a game from one to the other? For a platformer, wou...

If you're talking about virtual functions, those are done with a virtual method table (vtable). It's a bunch of function pointers included as part of the object, one for each virtual method. But if Mammal (and thus Dog and Cat) had a method named, let's say, roar(), would Animal have an entry in it...

Yes, and this is what I meant by "draw time". Okay. A switch statement can be used to implement a form of polymorphism, just one without specific support from the language. It can be implemented in assembly language using a jump table. I know about jump tables and switch statements, and t...

I'd save all the variables on a stack when each new one is called and keep track of how many are on the stack. Put a universal control value and universal output value and then when you escape, close them all. When you go 1 back, pull the vars you need a put the menu back on the screen. I've never ...

You mentioned menus before, and I want to know, what kind of loop would handle them. What about something like Dragon Warrior, where's there's lots of nested menus too? I suppose that you'd have to remember which menu is currently selected, and what index in the current menu is selected, and from th...

Personally, I wouldn't check for the game state every frame because that would be a waste of time and the code would look like spaghetti, specially if there are many states. I would do it more like this: 1) I forgot to wrap a while loop around the if's and else's. 2) I see the inner while loop now,...

The PPU is the master timebase for video; the TV locks on to its timing. This way the PPU can just output the signal and not need anything back from the TV. The game writes to PPU memory, and then the PPU reads this when it's generating the video frame signal output. Even if the game doesn't touch ...