Odd behavior in TMNT II, controller-related?

Odd behavior in TMNT II, controller-related?
by SargeSmash on 2016-01-05 (#161992)

So I was playing around with my new EverDrive, and I noticed I kept getting glitchy jumps TMNT II. I figured it was a problem with the cart, but I got out my legit copies, and they did the same thing. I've also dumped said carts myself, and tested them in the more accurate NES emulators (Nestopia, Nintendulator, puNES) and couldn't reproduce the effect.

I pull out my two spare systems, and the same thing happens on them. I swapped to a different power supply, and no change. As a last check, I happened to swap out my controller, and lo and behold, the effect is gone! Does anyone have any idea what might be going on that could cause such behavior? I don't plan on using that controller for anything other than parts from here on out, but it's very curious. I uploaded a video, just so folks can see what was going on.

https://www.youtube.com/watch?v=2va23iGN2FI

Re: Odd behavior in TMNT II, controller-related?
by Myask on 2016-01-05 (#161994)

The wiki wrote:

In Teenage Mutant Ninja Turtles II: The Arcade Game, when you jump with a left or right move while pressing up+down, the player character will move in unusual directions and speeds, possibly screen-wrapping.

The TAS wrote:

Pressing up+down in the air
- Makes your turtle move really fast to the upper left.
Pressing left+right+up in the air
- Makes your turtle move really fast to the lower right.
Pressing up+down+left in the air
- Makes your turtle move instantly to the lower left.
Pressing up+down+right in the air
- Makes your turtle move instantly to the lower right.
Pressing up+down+left+right in the air
- Makes your turtle move instantly up.

Your game is as-normal. Your controller is just a bit worn; the physical configuration of the D-pad is supposed to prevent pressing opposite directions at once. (As it takes you a bit to manage to trigger the behavior, the fulcrum's still mostly good at preventing this.) Contrastingly, it is terribly easy to press opposite directions on a computer keyboard, certainly more-so if you map them elsewhere like WASD. Because a fair number of games have code based on the assumption you cannot press opposing directions that breaks when you do, most emulators have an option that makes it not accept opposite directions simultaneously, so you don't run into this weird behavior by default. For instance:

Nestopia Options wrote:

Code:

Argument                         Values    Default 
input allow simultaneous axes    yes, no    no

Re: Odd behavior in TMNT II, controller-related?
by SargeSmash on 2016-01-05 (#161996)

Ah, didn't know the right place to look. Thanks for that!

Re: Odd behavior in TMNT II, controller-related?
by Snacks on 2016-01-11 (#162382)

you are pressing both axes. the main character sometimes appears in random place.
it occurs in TMNT2 (U) only.

Re: Odd behavior in TMNT II, controller-related?
by mikejmoffitt on 2016-01-14 (#162553)

This is also a problem with almost every cheapo third party controller I've ever used, especially the retro-bit stuff. The fulcrum is simply not large enough, even right out of the factory, so this can happen (and it also ruins the D-pad's precision!)

Re: Odd behavior in TMNT II, controller-related?
by Dwedit on 2016-01-20 (#162946)

Snacks wrote:

you are pressing both axes. the main character sometimes appears in random place.
it occurs in TMNT2 (U) only.

Occurs in other regions of the same game as well, not just (U).