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Flash Equipment > Difference between .gba and .mb?

#13997 - rogergba - Sat Dec 27, 2003 3:19 am

Hello,

I am using a MBV3 (Intelligent Multiboot Cable) with the MBLOAD.exe utility under Windows 98.
The hardware works fine. I have tested it thuroughly.

I can upload games, but only if I use the Pocket NES utility to convert a .NES rom into a ".gba" file and rename it to ".mb".

Here is the issue: If I download a ".gba" file from the demos section and rename it to a ".mb" file it will fail to work. It uploads fine, but always produces a blank screen when finished.

This MBLOAD utility (see http://ajo.thinknerd.com/gba/software.html ) cannot see a file without renaming it to ".mb".

Is there a functional difference between a .gba and a .mb file?
I also cannot load the renamed file using VisualBoyAdvance Emulator unless I change the name back to a .gba file.

I have checked that the .gba files do work in the emulator, but will not run after being renamed and uploaded to the real GBA.

All help appreciated.
:-)

I figure I might actually be the first to get this #!@$!$ MBV3 cable to work, but maybe someone here knows what is going on.

Strange that the .gba file generated by PocketNES can be renamed and still upload and run correctly.


The rundown:
a) .gba files created by PocketNES can be renamed to .mb files and will upload and work.
b) .gba files downloaded from the demo section that are renamed to .mb files will not work though they will upload.

#14000 - tepples - Sat Dec 27, 2003 5:22 am

A .mb program is compiled to run at a base of 0x02000000 (EWRAM) instead of 0x08000000 (ROM). You can't just take a .gba program and rename it to .mb; you have to pare its assets down and recompile it. (You usually can't do that to a proprietary program.) Some .mb programs, especially homebrew ones, will detect whether they're loaded from ROM or from EWRAM and will copy themselves to EWRAM if necessary.

If you're using a recent DevKit Advance, you can place the following line of code in one of your source files to trigger compiling for .mb:
Code:
int __gba_multiboot;

Some GameCube games send a .mb program to the GBA; experts may try intercepting those, or some pirate sites may carry those.
_________________
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-- Who?
-- You know, the human.
-- I think he moved to Tilwick.

#14027 - rogergba - Sat Dec 27, 2003 10:51 pm

I found a post near the bottom that dealt with this issue right after I wrote the article.

I have just gotten the MBV3 cable to also work with the Game Boy Advance Base Station for the GameCube. Thus, I can now edit my games on the BIG screen.
:-)

Very happy indeed.

I think my next question belongs in the programming area.

#14217 - splash_dad - Fri Jan 02, 2004 1:10 pm

I tried lots of combinations to get my MBV3 cable to work;

Pentium 3 Win2000
Pentium 4 Win2000
Pentium 1 Win95
Pentium 2 Win98

None of these worked.

Any hints on how you got yours to work?