This topic is for the purpose of discussing #6012: MUGG, Masterjun & Alyosha's GB Super Mario Land 2: 6 Golden Coins "game end glitch" in 00:46.08

Nice work! What was the main difference memory wise that allowed this to be possible on console v. the other run? Nothing against this run; just curious.

Nice work! What was the main difference memory wise that allowed this to be possible on console v. the other run? Nothing against this run; just curious.

It's not yet known if this one works on console, only that both Gambatte and GBHawk agree that it should. I don't know exactly where the timing error in VBA lies. It's pretty old and much work has been done to improve GB accuracy since the last run was made, so it could be any number of things. But the game doesn't use that much complicated PPU tricks, so it must be something relatively basic related to VBL timing. The basic idea is that this is a bad bank swap. The game assumes a HALT will be reached before an IRQ occurs, it then returns from the IRQ to an assumed bank, not the actual required bank. This has to happen exactly after the instruction JP #4067 in order for sensible code to be executed that reaches the game end glitch. This instruction is 16 cycles long, so that's the window to work with.

The run syncs with GBHawk to me, and it appears to be 9 frames faster compared to the current movie. However, it doesn't sync with Gambatte to me (BizHawk 2.3), due to longer loading times. Is there something that I'm missing?

Gambatte ends frames at different times (the actual real time is the same.) Here is the gambatte version: http://tasvideos.org/userfiles/info/47098069959194767

Temp encode: Link to video

I think that half a second can be saved with laborious efforts (pull off the bug quicker in the end). But that shall wait for another day..

I think that half a second can be saved with laborious efforts (pull off the bug quicker in the end). But that shall wait for another day..

Good luck if you are planning on doing that some time. It was only by pure blind luck that I found the current setup. Also, I was unable to find any setup on GBC regardless of picking Gambatte or GBHawk. Probably due to HALT working slightly differently. @fsvgm777: Thanks for the temp!

This TAS on other versions of the game: d11d94fa3c36b9f72e925070b66bb4f16d31001e *Super Mario Land 2 - 6 Golden Coins (USA, Europe) (Rev B).gb --> game crashes near at the final frames of the movie 96e3a314561fb394cdf51101f9178a32713c2313 *Super Mario Land 2 - 6 Golden Coins (USA, Europe) (Rev A).gb -->bizhawk 2.3 hangs up (freezes) at the final frames of the movie

Is it just me or does the transition from hub world to the first level seem unrealistically fast? Playing this game for years I knew how long it took the screen to transition from the hub world to the actual level.

This movie has been published. The posts before this message apply to the submission, and posts after this message apply to the published movie. ---- [3746] GB Super Mario Land 2: 6 Golden Coins "game end glitch" by MUGG, Masterjun & Alyosha in 00:46.08

I guess Alyosha isn't important.

The link to the downloadables seem to be broken.

There also seems to be something wrong with either the emulation or the video. At 0:11 the fade into the level is normally longer than what it seems like in the Youtube video. There is a split second of white screen that is missing in the video.

There also seems to be something wrong with either the emulation or the video. At 0:11 the fade into the level is normally longer than what it seems like in the Youtube video. There is a split second of white screen that is missing in the video.

I actually brought this up in the GBHawk thread: http://tasvideos.org/forum/viewtopic.php?p=472596#472596 What's weird is when I had tikevin83 playback the inputs for Mickey's Chase synced on both GBHawk and Gambette, both movies made it past the title screen just fine. So it isnt a problem with the encode, but just how GBHawk deals with Screen Transitions.

Is it possible to console verify GB runs? I have long speculated if the credits bug could be used in RTA.

Is it possible to console verify GB runs? I have long speculated if the credits bug could be used in RTA.

As far as I know, they have to be done in GBC mode (and GBA mode too.). Example of this case: [3687] GB Pokémon: Blue Version "Gotta Catch 'Em All!" by luckytyphlosion in 37:55.33. However, I have personally tried to convert this movie on GBC in GBA and it syncs all the way to the koopa shell throw, but the glitch doesn’t work. There’s probably a different method that has to be done in order to get the glitch to work.

Yes I did, I even ran the original movie file on it before I tested it.

So if I made a test movie in GBC mode, it might sync better?

It would need to be done with gbc mode and gba as gbc mode set to true to match the game boy player. But the current Gambatte core has some sync issues outside of the Pokemon Gen 1-2 so we're nit sure how well it will work even with that configuration.

It would need to be done with gbc mode and gba as gbc mode set to true to match the game boy player. But the current Gambatte core has some sync issues outside of the Pokemon Gen 1-2 so we're nit sure how well it will work even with that configuration.

Is the GBHawk core good enough instead for sync purposes?

It's unlikely to work differently in GBHawk as it was also tuned for cycle accuracy in Pokemon Gen 1. Lior's SameBoy core is more accurate than either core at passing test ROMs in general and we might want to enable it for gb/gbc/gbc in gba in the future instead of just SGB. However at the moment SameBoy doesn't even have cycle accurate RNG for Pokemon, so some more test ROMs are needed to cover enough corner cases to make SameBoy the clear winner.

MOD EDIT: Posts originally moved from the discussion thread of #6023: TiKevin83's GBC Pokémon: Yellow Version in 1:36:42.94. -Mothrayas

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</hr> Sorry for the late reply but I found this conversation interesting enough to post to. I’m glad the movie file got updated. This is state of the art stuff, and making sure things are correct to the furthest extent possible I think is pretty important. Just as food for thought, I’d like to point out that [3746] GB Super Mario Land 2: 6 Golden Coins "game end glitch" by MUGG, Masterjun & Alyosha in 00:46.08 is a ‘resync’ in exactly the same sense that this movie is. It is pure happenstance that it ended up being 9 frames shorter so that it superficially met the requirement of being an ‘improvement.’ But really it’s just slight timing differences in emulation. Also, the behavior that was missed in the original Pokémon run is very significant. Personally I think that not having it emulated puts it in ‘technical foul’ territory. Sure nobody knew at the time , but luckily Pokemon people had good R&D to move things forward .

You mean it's impossible to improve the old SML2 run using VBA v24?