Append a description file and NES ROMs (.NES format) to POCKETNES.GBA.
You can do this with third party utilities (like NEStoGBA or PocketNES
Rocket) or with MSDOS's COPY command. For example:
COPY /B POCKETNES.GBA+ROMLIST.TXT+ROM1.NES+ROM2.NES WHATEVER.GBA
The description file is a plain text file, each line containing the title
of a ROM. See the provided sample file (MENU.TXT) for more information.
If only one ROM is used, this file may be omitted.
So, you create a text file, each line is the game's title for the menu you'll see on screen.
example :
Mario
Mario 3
Zelda
Zelda 2
metroid
that's all
make the lines in the same order than your game when you cat (contatenate the binarie with roms).
windows :
copy /B POCKETNES.GBA+ROMLIST.TXT+ROM1.NES+ROM2.NES WHATEVER.GBA
on Linux
cat pocketnes.gba romlist.txt rom1.nes romx.nes > pocketnesroms.gba
If you don't want to use command lines, you can try existing tools, such as :
Thingy
nes2gba
PocketNES Menu Maker (I attached to that post the file I have!)
They are probably old version, as I didn't get them before pocketheaven closed.
The v9.99 (2006) contains all the documentation and changelogs, while the latest version I have (2008 11 10) is only the executable.
Edit: I had a 2012 version too (only the executable). I added to the attached files along with sources from 2013.
Edit:
Try the GBAtemp download section, maybe it has other versions of the GBA homebrew emulators or tools.