Converting .prg and .chr back to .nes file

[haogden]

Hi, I'm new here, and I have a question. A year ago, I made a hacked Super Mario Bros .nes file. I then converted, or split, the .nes file to a .prg and a .chr file. I now only have the .prg and .chr file. How can I make them back into a .nes file, as in what's the easiest way? Thanks in advance.

[Reaper man]

I feel this is more of a rom haking thread, so it has been moved.

As for your question... I believe if you merge the files using the "copy" command and then adding an iNES header, you'll get your rom hack back.... I think.

[haogden]

Thanks. And how would I add an iNES header? Sorry, I'm relatively illiterate when it comes to this stuff.

[Reaper man]

Open up an original SMB ROM in a hex editor, copy the first 16 bytes of the file, and then insert (NOT OVERWRITE!!) it in the beginning of your bare PRG + CHR ROM hack.

[haogden]

Ok, that I can do, I'll just copy the first 128 digits of SMB to the beginning of the bare PRG + CHR ROM hack. But what I can't figure out is how to merge the .prg and .chr file using the copy command. I assume you mean that I need to use command prompt. So in command prompt, what exactly do I need to type? I know how to get to the folder. In command line, I'll just type: C:\Users\Hoke\Documents\Emulation\Hacking>

That's where the .prg and .chr file are. But my question is, what do I type after the arrow? And after I merge the two files, I assume that I'll then rename the combined file to a .nes, right? Or will I do that after inserting the header?

Thanks again, I really appreciate your patience.

[Reaper man]

copy /b fileA + fileB fileAB

Also, make SURE PRG goes FIRST!

also, I said 16 bytes.... which in hex would be 32 digits, not 128.

Just copy offset 0x00-0x0F and you should be fine

[haogden]

I did exactly as you said and it did not work. When I go to load the .nes file in an emulator, I just get a gray screen. Any other ideas?