Flycast is a multiplatform Sega Dreamcast emulator. NOTE: No longer actively developed, use upstream repo for libretro from now on - https://github.com/flyinghead/flycast
[EDIT]
This issue seems to have no impact on games, since you can actually use 5+6 together even if the behaviour into the test menu is what I described a while ago. -_-'
Sorry for that.
I verified some problems with simoultaneous pressing of more than 3 buttons in Naomi games.
It can be replicated by launching ANY game (not only 6 buttons games) and entering JVS test - Input test.
This affects only games where combinations of buttons is required for some controls such as MvC2, CvS2 and so on.
The emulator allows you to map up to 8 buttons.
Using Keyboard you have more issues than using x360 pad, but none of the methods is 100% working.
I wasn't able to test all the possible combinations, but I discovered more than one:
KEYBOARD
Buttons 1+2 pressed:
adding 3 OK
adding 4 no go
adding 5 no go
adding 6 OK
adding 7 OK
adding 8 OK
adding 3 + 4 no go
adding 3 + 5 no go
adding 3 + 6 no go
adding 3 + 7 OK
adding 3 + 8 OK
adding 4 + x no go
adding 5 + x no go
adding 6 + 7 OK
adding 6 + 8 OK
adding 6 + 7 + 8 only the first one you pressed is ok, the second one is no go
JOYPAD (only differences compared to keyboard)
Buttons 1+2 pressed:
adding 4 OK
adding 5 OK
adding 4 + 5 OK
Apparently using the pad you can't sum up 6 buttons, as 5 and 6 will be alternative.
Again, all of the buttons are OK if you press them one at a time.
[EDIT] This issue seems to have no impact on games, since you can actually use 5+6 together even if the behaviour into the test menu is what I described a while ago. -_-'
Sorry for that.
I verified some problems with simoultaneous pressing of more than 3 buttons in Naomi games. It can be replicated by launching ANY game (not only 6 buttons games) and entering JVS test - Input test. This affects only games where combinations of buttons is required for some controls such as MvC2, CvS2 and so on.
The emulator allows you to map up to 8 buttons.
Using Keyboard you have more issues than using x360 pad, but none of the methods is 100% working. I wasn't able to test all the possible combinations, but I discovered more than one:
KEYBOARD Buttons 1+2 pressed:
JOYPAD (only differences compared to keyboard) Buttons 1+2 pressed:
Apparently using the pad you can't sum up 6 buttons, as 5 and 6 will be alternative. Again, all of the buttons are OK if you press them one at a time.