So not even the Ez 3in1 expansion pack, that has the option load a single game into "NOR" to mimic a single game cartridge?
Has anyone tested that out?
no, but i can try. I have a an ezflash 3in1, ezflash IV, supercard mini and an F2A at my disposal.
i'd assume at least the F2A to be able to do this, all the other ones probably have issues.
how can i check the connectivity works, what do i have to look out for?
EDIT:
I just tried with boktai. I whipped out lunar nights and my original bokati cartridge and checked what happend. in the options menu of lunar nights there was a new option called "solar sensor" so i knew what to look out for. I then flashed the rom (properly patched for each flashcart, just to be sure) to the NOR flash of the EZflash IV, Ezflash 3in1 and Flash2Advance. The supercard does not have a NOR so i left it at that. Here are the results (in the order i tried it):
1. Ezflash IV: option does not show up
2. Ezflash 3in1: option DOES show up
3. Supercard Mini: option does not show up
4. Flash2Advance 128M: option DOES show up
so in conclusion, the option would not show up on the two cards that have an SD Slot and a built in menu system to load different games. Whereas it would show up with both cartridges that are "storage only". So i guess the NDS identifies the GBA game via its header, the 3in1 and F2A will identify as the games flashed, whereas the EZIV and SC would boot into their menu first and therefore have a different header at boot. By this conclusion the EDGBA would not work either as the header would be different, but maybe krikzz would be able to have the header of the EDGBA to be set to whatever we want.
note that I was not able to test how the F2A would behave with a multi-ROM menu because my card is only a 128M model and therefore can only hold one of the Boktai games.
I was also not able to test how the pokemon games would behave so i do not know if you can tranfer pokemon from the F2A or 3in1 to the DS generations. This might fail since both cards use SRAM instead of FLASH or Eeprom or whatever the Pokemon games were using so i am not sure if the DS games would be able to see the savegame on the SRAM.