[Feature Request] biosnds7.bin, biosnds9.bin and firmware.bin usage

[ghost]

In the standalone version of DeSmuME you can use these files and boot to the BIOS before you start a game just like how it functions on a real DS.

Would it be possible to implement/backport this from the standalone for use in the Libretro core? The standalone also features the option to save/load changes made in the firmware to a separate file which resides in the Battery folder.

This is actually the only thing I miss in the Libretro core being able to use the BIOS files.

Thanks in advance!

[bearoso]

The Desmume core recommends you don't do this because it doesn't have good support for it. It shouldn't be too hard, though.

[ghost]

Thanks for your reply @bearoso

I just thought now would be a good time to implement this since the current DeSmuME core is up to par with the TASVideos/desmume repo these days.

I didn't know using the original BIOS files wasn't recommended, haven't really noticed something wrong when used in the standalone version, it works perfectly fine and it's a nice addition to an authentic experience.

I would like to point out though that the core is pretty much flawless as it is, and this is just a suggestion. It's nice to boot up a game to the DS menu and see your name and click the game icon to start the game.

[andres-asm]

It should be easy, just add RETRO_ENVIRONMENT_SUPPORTS_NO_GAME in retro_set_environment (so it shows a "Start Core" option) in the menu.

Then in retro_load_game handle the case where no game is passed properly.

[bearoso]

(In the words of Dr. Light) Yes, but it also entails looking for the appropriate files in the system directory and adding a switch whether to use the bios interrupt routines instead of the emulated ones.

[bearoso]

Here's the thing:

• Desmume core doesn't allow booting into BIOS without a game, the code assumes one is there, so you need one of those.
• You'll need bios9.bin bios7.bin and firmware.bin in your system folder.
• I couldn't get the game to boot from the BIOS screen in jit mode, and the source code indicates it is hit or miss with the jit, so it's interpreter mode only.
• I added two options, one just globally enables every firmware file and the bios swi, the other allows booting into the bios interface. The options are getting a little cluttered without having submenus, so I was reluctant to add each option individually.

[ghost]

Thank you @bearoso It works beautifully, AMAZING JOB!

There is only one thing left for this feature to be complete, the standalone can save changes made in the firmware to a firmware.dfc file which is saved/loaded to/from the Battery folder.

Would it be possible for the core to utilize the saves folder for the firmware.dfc file? The option in the standalone version of DeSmuME is called Load User Settings from file

[bearoso]

Done. Enabling it was just a flag.

[ghost]

@bearoso You Came, You Saw, You Conquered!

Thanks for all you have done, now there is no reason to stay with the standalone for me anymore.

God bless you sonny!