Hacking GameBoy Micro MP3 Player

[Dagatahas]

Hi,

As I read through the forum I became interested in buying a GameBoy Advanced Micro which one of the stores I go to say they sell for about $50(others quote it at $70-$75). As I do not have a Slot-2 cart for my NDSLite I began rummaging around to find a cart that would work on a GBMicro.(NDSLite is awkward to use on the run)

I have spent the past couple of days browsing through the site and the web looking for a way to use a GBMicro as an MP3 player with a shuffle function. I would like to ask if anybody can point me to the direction of a cart with up to 2GB Micro SD support that can play MP3s or a homebrew that will do the same on say EZ-Flash IV MiniSD(only locally available cart I can find). After a lot of bumps and turns this is the basic data that I have:

For DSL and GBA

M3 DS Real + M3 GBA Expansion Pack

http://gbatemp.net/index.php?showtopic=68277
http://www.consolesource.com/ecomm/catalog...ack-p-2821.html

EZ Flash V + EZ-FLASH 3in1 Expansion Pack -> NO REMOVABLE MEDIA IN GBA SLOT-2

http://www.ezflash.cn/products.htm

EZ Flash IV Lite

http://gbatemp.net/index.php?showtopic=36216 -> Has Micro SD external slot


GBM Dedicated MP3 Player
http://en.wikipedia.org/wiki/Play-Yan

ROCKSoft Online
http://www.rocksoftonline.com/index.php?main_page

->>> MOONSHELL DOES NOT WORK IN GBA

 

[DanTheManMS]

Here's the core issue: the GBA runs at 16 MHz. That's it. It's not enough to decode mp3 in real-time, and thus no mp3-playing software was ever created, at least nothing that runs solely on the GBA with any flash cart.

Thus, if you want actual MP3 compatibility, the official Nintendo MP3 player is your only option since it contains extra hardware on-board to play the audio files. There are alternatives, but they require conversion first:
1. GBA Movie Player hardware and software. Converts audio to *.gbs (Game Boy Sound) format first.
2. Music Player Advance with any flash cart. Requires a rather lengthy (in my opinion) process for converting files first to WAV format and then to MPA format, then injecting into the *.gba rom file.
3. GBA GSM Player with any flash cart. My personal choice. Use some program like Wavepad or Audacity to first convert the files to high-quality WAV format (preferably with batch processing to do multiple at once), drag and drop into the "wavs" folder provided, and run the "go.bat" file which simultaneously converts the files to GSM format and injects them into the *.gba rom file. After this is done, you can delete the wave files so that it doesn't try to convert them to GSM format every single time you run the go.bat file.

With all these conversions, audio quality will drop, and that's simply a trade-off you have to accept if you want the .gba file to be able to run on any flash cart. I used GSM Player for over a year until I got my DS, and it worked, but I did notice the improvement once I switched to Moonshell.

On a pure side note, it's a shame that 16 MHz isn't enough to do it. Lick managed to get mp3 decoding working on the DS's ARM7, which is 33 MHz, but it took a lot of work to optimize it enough for it to be possible.

 

[Dagatahas]

Argh, I was afraid it was a processor or memory issue.

Thank you for your reply and the information you supplied. It also answered a couple other questions I was researching.

 

[stuffnflufff]

can the NMP3P play GBA roms though?

 

[Krestent]

can the NMP3P play GBA roms though?

What's an NMP3P?

 

[Ultralex]

can the NMP3P play GBA roms though?

The MP3 player is from Nintendo!
Do you think thay'd support Piracy!?

 

[cavinsmither]

its cheap combined with a 1GB SD card, I was thinking between this and a Creative. It's better in an SP or Micro, is that. Far more portable.