Proto talk:Sonic the Hedgehog 2 (Genesis)/Simon Wai Prototype

Potentially Interesting

I think I found something potentially interesting, but I'm not 100% sure if anyone is interested (since all of the text is Chinese and there are annoying pop-ups): https://web.archive.org/web/20110611204231/http://www.emu999.net/html/info/zhongyingduizhao/20081015/25908.html (Quick Guide: "动作" indicates a pre-production version; 英 indicates an English version; 日中 indicates a Japanese version; and "无法运行" means the person who wrote the guide could not get it to work(possibly a bad dump))--From: divingkataetheweirdo 22:25, 22 January 2011 (EST)

Was it pirates or devs?

This is regarding the possibility of the ROM being altered by pirates to remove an instance of the Sega screen before the copy of the ROM we have was distributed.

‎BMF54123:"if this was true they likely would have removed it [the Sega copyright] from the title screen as well"

It's far less than likely. You see, in order to skip the Sega screen on startup, you'd have to change one single byte. Said byte is part of a system that is seemingly common in Mega Drive titles. This system involves 'screen modes' of sorts. This is Sonic 2 Simon Wai Prototype's list of screen modes.

• Sega Screen
• Title Screen
• Demo Mode
• Normal Gameplay
• Special Stage

They are all referred to by numbered IDs. Going by this information, all you should have to do to skip the Sega screen is find where the screen mode is set to the ID of 'Sega Screen', and change the number in the code to the ID of 'Title Screen'. This is exactly how the Sega screen was bypassed.

The one line of code that was edited to achieve this is part of a block of code that I have seen in other Mega Drive games. It begins and ends at the very beginning of the ROM. It's possible that pirates were familiar with this common, easy-to-locate code, and were aware that the Sega screen was a screen mode, as is also the case in other games. So they used their prior knowledge to make this one simple change. From my research, this is the only instance of the screen mode code being changed.

Prior knowledge of other games couldn't help in finding the other instances of the screen mode being set to 'Sega screen', such as that when demos end. That piece of code, not being part of a common and potentially well known template, would have been too difficult to track down. Likewise, removing the copyright text on the title screen is not a simple thing to do. At the very least, it isn't as simple as changing one byte. The copyright text is displayed by a sequence of instructions that load the mappings of the copyright text into RAM, and then have the VDP use it. This code is buried inside the setup code of the title screen, where a lot of VDP related code resides.

tl;dr it would simply be too difficult to remove the title screen copyright text. It would also be too difficult to change every line of code that sets the screen mode so it never sets it to 'Sega screen's ID. It would, however, be very easy to change a single number in a short, easy to locate, and common piece of code. That just so happens to cause the most noticeable instance of the Sega screen appearing.

Here's my question, why would anyone but a pirate make this one tiny change? The Sega screen can by interrupted and skipped in the prototype by spamming the start button, so I don't see Sonic Team removing this one call (of many) to the Sega Screen just to save time during the game's demonstration. Toasty.C (talk) 20:37, 26 July 2014 (EDT)

Clarification on attempting water levels on 2p mode

Here's a correction/clarification on 2p water levels. Apparently if you force a water level to go into 2 player with the Pro Action Replay codes FFFFD8:0001 FFFFD9:0001, then the game crashes. However, as seen in this video http://www.youtube.com/watch?v=XdKEEWx6sdk&feature=youtu.be if you force 2 player via Chemical Plant Zone, then the game will be confused and go corrupted 1 player. This is because the game is trying to go one player, but it has to decide between crashing and becoming corrupt. If you use the PAR code, then it will crash because you're forcing it via the level Select. If you go via CPZ act 1, then it will load a corrupted 1 player version because it is trying to load the 2 player version of the stage based on the CPZ act 1 data, but it's normally forced to go into 1 player version of that stage otherwise. -Hexatendo (talk) 22:37, 30 December 2014 (EST)

HTZ's song description isn't "complete"

If you compare some of the instruments with the final version, you'll notice some slight differences between them. See for yourself. --MegaMCAlly (talk) 17:53, 3 July 2015 (EDT)

Special stage IS in the game??

I've played around with some code in a disassembly of this proto and found the special stage is playable?? It seems to act the same as the Aug 21 proto's special stage being a corrupted version of Sonic 1's special stage (though the background scrolling is still intact). Interesting thing to note here is that it does use the Sonic 2 special stage music, though that's probably a coincidence. I have a video showing it here. — The preceding unsigned comment was added by MCTravisYT (talk • contribs)

Leak?

> Leaks are: Things that were physically stolen and that stolen copy released online.

I think it might be classified as a "leak" since the cartridge was stolen from somewhere else and was widely pirated, but it was stolen years before, so idk if I can put a {{Leak}} template here. --SuperfishMEMZ (talk) 08:20, 20 February 2022 (UTC)

Question about the ROM (out of pure curiosity)

On this prototype's page on the Hidden Palace website, it says that the prototype's ROM was possibly altered by pirates. Is there any evidence at all that the ROM was altered? If so, is there any possible way of getting potentially damaged data restored? This is just my pure curiosity, I'm not looking to add this to the page or really research it. Could anyone answer my questions? I'm a little nervous that this might not be the right page to put my question (because it isn't about unused content). If this isn't the right page, could someone point me in the right direction to ask about this, please? I'm a new user, so I'm trying to figure things out. Thanks! -- FanOfRosalina2007 (talk) 03:41, 7 November 2023 (UTC)