Bubble Bobble (Arcade) behavior is different in MAME vs FBNeo

RetroArch Windows devices
#1

I’m running the same exact ROM with either MAME (0.237, with the recent input lag fix) and FBNeo.

The behavior of the monsters is very different in level 5.

In FBneo, once the level starts and you can control your dragon, you have just about enough time to jump to the top platform and bubble trap the monster at the top (without the speed powerup). But in MAME you can’t, the moment you start moving, the top monster also moves so if you do the same you will end up under it and you will be killed if you jump on top.

It’s like in MAME, the monsters are faster, or react faster or something.

Which one is the correct behavior? I wonder if the recent input lag fix broke the MAME core in some way?

1 Like
#2

I would suggest checking youtube for real hardware footage.

1 Like
#3

I also tried a slightly older core (version 0.232) and it looks the same as FBNeo (you have enough time to trap the monster).

So far i haven’t found any footage of real hardware indicating 0.237 (with the fix) is correct. But any other footage seems to agree with FBneo/0.232.

Edit: This claims it’s real PCB

In level 5 it seems there’s enough time to go to the top (even though the player fails to do so).

2 Likes
#4

Ok, i replayed the game in 0.237 and this time the monster behaved just like in the other versions…

This is weird but…

…i did made a save state just before level 5 started, in my previous play where the problem appeared, so i can reproduce it every time i load. Here is the save:

You will see that the monster on top starts running very early. I wonder why though. Is it because saving states somehow messes with the game’s timing? Was it a random occurrence? it’s pretty odd, i don’t remember seeing this before.

1 Like
#5

Yes, savestates will mess with the internals of a game if they are of poor quality. I don’t think MAME cares a lot about savestate support : i keep seeing games flagged as having no savestate support at all.

1 Like