There are several ways to boot the old flashcard.
- You can try launching the flashcard from
TWiLightMenu++.
(Recommend)
Set Unlaunch startup items: TWiLightMenu++
TWiLightMenu++ → SELECT menu → Launch Slot-1 card
Or set autoboot cartridge: TWiLightMenu++ Misc.settings → Auto-start Slot-1:Yes
(If you want to cancel autoboot cartridge: hold SELECT button while launching TWiLightMenu++, and you will enter the settings.)
- Use Unlaunch to boot the old flashcard.
(Note that when launching the cartridge this way, the Wi-Fi status LED will not light up, but the Wi-Fi is actually on.)
Set Unlaunch startup items: TWiLightMenu++'s Slot-1 Launcher(
sdmc:/_NDS/TWiLightMenu/slot1launch.srldr)
-
Install HiyaCFW (created using a lower system version of DSi NAND), and boot the old flashcard from HiyaCFW.
- Use
TDT to install old 'DSi Firmware', and downgrade the DSi.
(Back up the NAND first.)
- There is also a
Simple DS Slot-1 Launcher, but I tried it, and it cannot start some old flashcards.