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.nes roms PAL to NTSC? (My case SOLVED)

.nes roms PAL to NTSC? (My case SOLVED)
by on (#122549)
Hey all, so about 10 years ago I made my own Mario game. At the time I didn't realize I had used a PAL version of it. No problem, I'll just turn on PAL emulation. NOW after learning about homebrews and stuff i'd like to put this game on a cart for myself. The rom runs perfectly well, just too fast.

Now since im guessing the .nes file is really just hex code, is there ANY way to modify its code to switch to what an NTSC NES needs?

OR is there a way I could import the level data into a different NTSC SMB rom?

I did just about EVERY single level I could and I can't really go back and use the same editor and re-make the game as it was confusing to take enemy data from other levels etc (unless theres a great SMB level editor that works from scratch).

Any ideas or workarounds for this? The game is STUPIDLY hard and running fast just makes it harder to control at times.

==========EDIT==========
FIXED! This idea was given to me by tatsui and it worked! I tried this idea out last night in a different way but didn't work. This way did. So huge thanks to him for solving this puzzle for me.

- create an ips file by comparing your edited pal rom versus a clean pal rom
- apply the ips file on a clean ntsc rom
Re: .nes roms PAL to NTSC? (Hear me out)
by on (#122550)
Very short answer, no.
Re: .nes roms PAL to NTSC? (Hear me out)
by on (#122553)
Can you point me in the direction of any links that explain why? Just so I can understand it a bit better.
Re: .nes roms PAL to NTSC? (Hear me out)
by on (#122556)
As I understand the question, you have made a hack of the original SMB, not really 'your own Mario game' (a game programmed from scratch). So your question is about romhacking of a particular game, not a general programming/homebrewing question, and the changes of getting help is greater if you try dedicated places, like romhacking.net.
Re: .nes roms PAL to NTSC? (Hear me out)
by on (#122557)
Some slight code changes were made between the NTSC and PAL versions of Super Mario Bros. A year ago, autoreverse made a disassembly of SMB1 (E), marking all differences from doppelganger's published disassembly of SMB1 (JU). I went down the disassembly and summarized each difference. I imagine SMB1 (E) will play on an NTSC NES, but at the wrong speed.

What I'd suggest you do is export the edited levels to a file, then import them to the NTSC version. If your editor doesn't support exporting levels, get a different editor. And I agree that romhacking.net would be the best place to get help on this project.
Re: .nes roms PAL to NTSC? (Hear me out)
by on (#122559)
guitarzombie wrote:
Hey all, so about 10 years ago I made my own Mario game.

If you had made your own Mario game you'd probably know the answers to your questions... it appears you have hacked the original Mario ROM, is that it?

Quote:
Now since im guessing the .nes file is really just hex code

If you follow that logic, then every piece of digital content ever created is just "hex code". Can you easily edit a Blu-ray video simply because it's just hex code?

Quote:
is there ANY way to modify its code to switch to what an NTSC NES needs?

No. The timing of NTSC and PAL consoles is different in several areas (even the sound frequencies are different), so games for each region are (or should be, some PAL versions are lazy conversions) specifically coded for the timing of the console it was made for. Converting a game from one region to another would involve changing the music engine as well as physics, timers, and anything else that's locked to the console's frame rate. This is a per-game deal that can only be done after a deep analysis of the game's code, which makes the whole process incredibly time-consuming.

Quote:
OR is there a way I could import the level data into a different NTSC SMB rom?

Depending on what you changed, that might be possible. You could possibly use a tool to compare the PAL original and the hack, and then you would take note of the original hex sequences and what they have been changed to. If you can find the same original sequences in the NTSC ROM, you can probably apply the same changes. Sounds like this would be very tedious to do by hand, so it would be much easier to code a tool for this.
Re: .nes roms PAL to NTSC? (Hear me out)
by on (#122560)
tokumaru wrote:
If you had made your own Mario game you'd probably know the answers to your questions... it appears you have hacked the original Mario ROM, is that it?


Apologies. I should have been a bit more careful with my words. I used a level editor.

tokumaru wrote:
No. The timing of NTSC and PAL consoles is different in several areas (even the sound frequencies are different), so games for each region are (or should be, some PAL versions are lazy conversions) specifically coded for the timing of the console it was made for. Converting a game from one region to another would involve changing the music engine as well as physics, timers, and anything else that's locked to the console's frame rate. This is a per-game deal that can only be done after a deep analysis of the game's code, which makes the whole process incredibly time-consuming.


Ahhhh.

BTW as for the hex comment, I mean theoretically yes but we're dealing with data on a lot smaller of a scale. And like I said instead of re-doing the entire game again I'm trying to see A) if its possible and B) if it IS possible, how much work would it be compared to the amount of work for me to do it all over again and figure out what I took from what levels. ANYWAY, i'll check around on romhacking's page. Thanks for all the info and insight