2.When you finish download you can download a ROM file of DIAMOND/PEARL....
NOTE: You can download the ROM in torrents or any other website that you know (i have no idea of that exact web location for DIAMOND AND PEARL ROM)
3. put the GBA BIOS file in the emulator's folder, and rename it to "gba.rom"
4. run No$GBA.exe
5. pick a GBA image (no ZIP)
6. go to "Options" / "Emulation setup"
7. increase the number of "Emulated Gameboys"
8. in "Link Gamepaks", set "Gamepaks in all GBA"
9. in "Reset/Startup Entrypoint", set "GBA BIOS (Nintendo logo")
10. click OK, you should then see 2 GBA screens side by side
11. right click on the left window, click on "Link" so that the window comes back to normal.
12 then redo the right-click and click "Link" , and here we go, the 2nd gameboy does boot!