Homebrew Question about NDS backup playback

[YamiJustin]

So I have an r4 card that I use to play all my DS backups and the compatibility is really good (except Pokémon Platinums bag menu lags a little bit for some reason). That being said why is it that you can’t simply play DS backups from the 3DS SD card with the same 100% compatibility as when it’s being read from the cartridge slot? I know they allow you to play DS games from SD now but I read it’s still not as good as a flashcart?

 

[godreborn]

I don't know the percentage, but it's not 100%, no. one game I know that doesn't work is golden sun. it works with flash cart only.

 

[YamiJustin]

I don't know the percentage, but it's not 100%, no. one game I know that doesn't work is golden sun. it works with flash cart only.

why is compatibility even an issue when the 3DS has the DS hardware built in?

 

[godreborn]

I don't know the specifics. you'd have to ask @Robz8 , the developer of twilight menu++

 

[RocketRobz]

why is compatibility even an issue when the 3DS has the DS hardware built in?

1. The read timings are different, which causes issues in a few games.
2. On DSi, reading from the SD card would cause issues related to RTC in a few games.
3. Some AP measures could also cause issues, but most of those are already patched out.

Since DS games cannot natively read from the SD card, they have to be patched to do so, and the process could introduce some issues that normally don't happen in DS games.

 

[godreborn]

golden sun does work on both the ds and the 3ds through twilight menu++ if you have a flash cart as I've tested it. it's usually the game I test on my ds whenever I install a new twilight menu. I don't know if via the 3ds sd card -- it being playable-- is possible. it might be, just in a future update.