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What are the differences between these two ROMs?

I don't know, but I HAVE a clue:
I have a downloaded version of Sonic 2 and a Sonic 2 cartridge. The Zone 1 & 2 music plays rather quickly on the downloaded version, although that is NTSC, and I have a PAL TV.

That's just the PAL/NTSC difference.

Do you have both of those roms?
I assume that 1.0 = [V0] and 2.2 = [V1] as Meka/SMS Checker would call them.
If you do, why not run a byte comparison tool and find where they differ.
Then you could compare those results to Hivebrains hacking guide. I would do this myself but I can't find the 2.2 version of the rom.

There doesn't seem to be an obvious difference between the two; the differences seem to be in data blocks. It may be that they changed some of the levels' underlying data format, or maybe just changed the levels a bit. The result is that a lot of the code is shifted by a few bytes and this makes a huge number of false "differences" appear. The only way to find a difference is to have pleople play through the games and see if they can find any differences; it's going to be hard to figure out otherwise.

It took me a few hours to figure out the effect of the 1 byte difference in the alternate version of Phantasy Star.

According to the hacking guide, many of the changes lie in the level data for Sky High act 2 and Gimmick Mountain act 1. I've just run the two versions side-by-side and there's an obvious change in GM1 - in the very first room, the v1 game has a spring on the floor, whereas the v0 game has none.

I can even give a pretty good guess as to why this change was made. When playing the game on real hardware years ago, on a couple of occasions the bottom "wheel" would go wrong and you would not be able to grab onto it. Without this, you cannot progress in the level. Probably what happened is that this is a bug in the game, and rather than fix it, the spring was added so that on the rare occasion that it occurs, you can bypass the wheel and continue the level.

The change made to Sky High act 2 seems to be to do with the top row of tiles - on the v0 version, it is possible, using the hang glider from the start of the level, to go off the top of the screen. This causes you to lose the hang glider and fall.

In v1, once you reach the top of the screen, you remain on-screen and keep the hang glider, merely being pushed against the "roof" of the level. This makes it hugely easier to reach the Chaos Emerald with the hang glider.

DMEnduro wrote

Do you have both of those roms?
I assume that 1.0 = [V0] and 2.2 = [V1] as Meka/SMS Checker would call them.
If you do, why not run a byte comparison tool and find where they differ.
Then you could compare those results to Hivebrains hacking guide. I would do this myself but I can't find the 2.2 version of the rom.

I have both versions of this game.About running a byte comparison tool, i can't , cause there's no such tool for Series60/Sega Dreamcast platform.

Thanks for detailed info, Paul Baker.I'll check it and try to find some other differences, if there's some.About that bug with the wheel of stell in Gimmick MT act 1, it's already happened with me and my brother when we were just kids.The wheel becomes a "ghost", and it's not possible to grab on it anymore.The only thing we could do was wait until the time reaches 9:59.

thanks guys, for the replies.But were these two versions released as cartridges too?Or only one was really released?

alb3530 wrote

But were these two versions released as cartridges too?Or only one was really released?

I've got both on cartridge.

Paul Baker wrote

alb3530 wrote

But were these two versions released as cartridges too?Or only one was really released?

I've got both on cartridge.

I've got only version 1.0 in cartridge format.I don't know if the other was actually released here in Brazil

I'm guessing that Gimmick Mountain wheel bug is somewhat common then, because I remember it happening to me.
Also, that Sky High chaos emerald is, in my opinion, the hardest emerald to get in the game, even if you know where it is. (The second hardest is probably Gimmick Mountain, cause you have to know where to jump through. Easy when you know how.)

I am sort of upset that there is a version that makes getting that emerald so much easier.

How do you tell the difference between the versions on cartridge format?
and is this a region thing eg, only on pal?

Emuaust wrote

How do you tell the difference between the versions on cartridge format?

Probably the easiest way is to use the level select to get to Gimmick Mountain 1, and see whether or not there is a spring on the floor. Of course a more accurate way (as there may be further, as yet undiscovered versions) would be to dump the cartridge and check its contents.

Quote

and is this a region thing eg, only on pal?

I'm pretty sure SMS cartridges are region-neutral.

I am aware of the region locking or lack of for the SMS I was meaning
is the different versions released in different parts of the world?

Well, the only way to know that is to have different people in different parts of the world try it and report their findings; and remember that absence of evidence is not evidence of absence.

well i have around 15 copys of Sonic 2 and the all seem to be the first
version, pity. Im in australia by the way and have the variants like blue cartridge
label and normal label and no difference.

And well quoted Maxim

Emuaust wrote

well i have around 15 copys of Sonic 2 and the all seem to be the first
version, pity. Im in australia by the way and have the variants like blue cartridge
label and normal label and no difference.

the same here, i've never seen the second version in cartridge format.I Think it didn't come to Brazil

To DMEnduro, and the other guys that are curious to see the differences between the versions but can't find 1.0 or 2.2, i've uploaded the two versions of this ROM

Paul Baker wrote

The change made to Sky High act 2 seems to be to do with the top row of tiles - on the v0 version, it is possible, using the hang glider from the start of the level, to go off the top of the screen. This causes you to lose the hang glider and fall.

In v1, once you reach the top of the screen, you remain on-screen and keep the hang glider, merely being pushed against the "roof" of the level. This makes it hugely easier to reach the Chaos Emerald with the hang glider.

I have been looking at this again and have found an interesting issue. If you jump from directly below the hang glider on Sky High act 2, then press left while it ascends, you are immediately teleported above the top of the screen. On v1, this can cause you to get stuck, apparently on top of the "roof".

Also, the Game Gear version of Sky High act 2 matches Master System v0: It has no "roof".

I checked my Red labeled Tectoy Sonic 2 cartridge, and based on the SHZ2 roof and the spring on GMZ1 factors, I am the owner of a v2.2 version of the game! Is it rare?

Sorry for the double post, but I found some other relevant differences in Sky High 1 and 2.

In the right down corner of the screen, in the 1.0 rom (or V0), there is a falling bridge (when falling off the glider) which was removed from version 2.2 (or V1). There is also a bug related to it, if you run the entire bridge and fall you will not die, being able to walk above the bottom of the screen. Jumping will cause you to lose rings/die as it normally works. The bug seems to affect the platform edges for the rest of the stage. Sonic will run in the air for a second and come back to the platform. This is notable on the platform where the glider is.

Sky High Zone 2 has some layout differences as listed by Esrael (Neto) at Sega Brasil forums:
http://www.sega-brasil.com.br/forum/viewtopic.php?f=1&t=4566&p=50989#p50...

EDIT: added more information, reorganized post

Author	Message
alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	Differences between Sonic 2 v1.0 and Sonic 2 v2.2? Posted: Fri Mar 24, 2006 7:36 pm
alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	What are the differences between these two ROMs?

thematrixeatsyou Joined: 27 Feb 2006 Posts: 37 Location: Wellington, New Zealand	Posted: Mon Mar 27, 2006 6:11 am
	I don't know, but I HAVE a clue: I have a downloaded version of Sonic 2 and a Sonic 2 cartridge. The Zone 1 & 2 music plays rather quickly on the downloaded version, although that is NTSC, and I have a PAL TV.

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14740 Location: London	Posted: Mon Mar 27, 2006 8:11 am
	That's just the PAL/NTSC difference.

DMEnduro Joined: 27 Apr 2005 Posts: 420 Location: Australia	Posted: Mon Mar 27, 2006 9:29 am
	Do you have both of those roms? I assume that 1.0 = [V0] and 2.2 = [V1] as Meka/SMS Checker would call them. If you do, why not run a byte comparison tool and find where they differ. Then you could compare those results to Hivebrains hacking guide. I would do this myself but I can't find the 2.2 version of the rom.

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14740 Location: London	Posted: Mon Mar 27, 2006 10:29 am
	There doesn't seem to be an obvious difference between the two; the differences seem to be in data blocks. It may be that they changed some of the levels' underlying data format, or maybe just changed the levels a bit. The result is that a lot of the code is shifted by a few bytes and this makes a huge number of false "differences" appear. The only way to find a difference is to have pleople play through the games and see if they can find any differences; it's going to be hard to figure out otherwise. It took me a few hours to figure out the effect of the 1 byte difference in the alternate version of Phantasy Star.

RetroSpark Joined: 08 Dec 2005 Posts: 488 Location: Melbourne, Australia	Posted: Mon Mar 27, 2006 10:54 am
	According to the hacking guide, many of the changes lie in the level data for Sky High act 2 and Gimmick Mountain act 1. I've just run the two versions side-by-side and there's an obvious change in GM1 - in the very first room, the v1 game has a spring on the floor, whereas the v0 game has none. I can even give a pretty good guess as to why this change was made. When playing the game on real hardware years ago, on a couple of occasions the bottom "wheel" would go wrong and you would not be able to grab onto it. Without this, you cannot progress in the level. Probably what happened is that this is a bug in the game, and rather than fix it, the spring was added so that on the rare occasion that it occurs, you can bypass the wheel and continue the level.

RetroSpark Joined: 08 Dec 2005 Posts: 488 Location: Melbourne, Australia	Posted: Mon Mar 27, 2006 11:00 am
	The change made to Sky High act 2 seems to be to do with the top row of tiles - on the v0 version, it is possible, using the hang glider from the start of the level, to go off the top of the screen. This causes you to lose the hang glider and fall. In v1, once you reach the top of the screen, you remain on-screen and keep the hang glider, merely being pushed against the "roof" of the level. This makes it hugely easier to reach the Chaos Emerald with the hang glider.

alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	Posted: Mon Mar 27, 2006 5:26 pm
alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	DMEnduro wrote Do you have both of those roms? I assume that 1.0 = [V0] and 2.2 = [V1] as Meka/SMS Checker would call them. If you do, why not run a byte comparison tool and find where they differ. Then you could compare those results to Hivebrains hacking guide. I would do this myself but I can't find the 2.2 version of the rom. I have both versions of this game.About running a byte comparison tool, i can't , cause there's no such tool for Series60/Sega Dreamcast platform. Thanks for detailed info, Paul Baker.I'll check it and try to find some other differences, if there's some.About that bug with the wheel of stell in Gimmick MT act 1, it's already happened with me and my brother when we were just kids.The wheel becomes a "ghost", and it's not possible to grab on it anymore.The only thing we could do was wait until the time reaches 9:59. thanks guys, for the replies.But were these two versions released as cartridges too?Or only one was really released?

RetroSpark Joined: 08 Dec 2005 Posts: 488 Location: Melbourne, Australia	Posted: Mon Mar 27, 2006 8:22 pm
	alb3530 wrote But were these two versions released as cartridges too?Or only one was really released? I've got both on cartridge.

alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	Posted: Mon Mar 27, 2006 11:33 pm
alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	Paul Baker wrote alb3530 wrote But were these two versions released as cartridges too?Or only one was really released? I've got both on cartridge. I've got only version 1.0 in cartridge format.I don't know if the other was actually released here in Brazil

DMEnduro Joined: 27 Apr 2005 Posts: 420 Location: Australia	Posted: Tue Mar 28, 2006 12:05 pm
	I'm guessing that Gimmick Mountain wheel bug is somewhat common then, because I remember it happening to me. Also, that Sky High chaos emerald is, in my opinion, the hardest emerald to get in the game, even if you know where it is. (The second hardest is probably Gimmick Mountain, cause you have to know where to jump through. Easy when you know how.) I am sort of upset that there is a version that makes getting that emerald so much easier.

Emuaust Joined: 10 Aug 2005 Posts: 79	Posted: Tue Mar 28, 2006 8:44 pm
Emuaust Joined: 10 Aug 2005 Posts: 79	How do you tell the difference between the versions on cartridge format? and is this a region thing eg, only on pal?

RetroSpark Joined: 08 Dec 2005 Posts: 488 Location: Melbourne, Australia	Posted: Tue Mar 28, 2006 9:16 pm
	Emuaust wrote How do you tell the difference between the versions on cartridge format? Probably the easiest way is to use the level select to get to Gimmick Mountain 1, and see whether or not there is a spring on the floor. Of course a more accurate way (as there may be further, as yet undiscovered versions) would be to dump the cartridge and check its contents. Quote and is this a region thing eg, only on pal? I'm pretty sure SMS cartridges are region-neutral.

Emuaust Joined: 10 Aug 2005 Posts: 79	Posted: Tue Mar 28, 2006 9:30 pm
Emuaust Joined: 10 Aug 2005 Posts: 79	I am aware of the region locking or lack of for the SMS I was meaning is the different versions released in different parts of the world?

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14740 Location: London	Posted: Wed Mar 29, 2006 8:03 am
	Well, the only way to know that is to have different people in different parts of the world try it and report their findings; and remember that absence of evidence is not evidence of absence.

Emuaust Joined: 10 Aug 2005 Posts: 79	Posted: Wed Mar 29, 2006 10:08 am
Emuaust Joined: 10 Aug 2005 Posts: 79	well i have around 15 copys of Sonic 2 and the all seem to be the first version, pity. Im in australia by the way and have the variants like blue cartridge label and normal label and no difference. And well quoted Maxim

alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	Posted: Wed Mar 29, 2006 1:05 pm
alb3530 Joined: 15 Feb 2006 Posts: 70 Location: Brazil	Emuaust wrote well i have around 15 copys of Sonic 2 and the all seem to be the first version, pity. Im in australia by the way and have the variants like blue cartridge label and normal label and no difference. the same here, i've never seen the second version in cartridge format.I Think it didn't come to Brazil To DMEnduro, and the other guys that are curious to see the differences between the versions but can't find 1.0 or 2.2, i've uploaded the two versions of this ROM

RetroSpark Joined: 08 Dec 2005 Posts: 488 Location: Melbourne, Australia	Posted: Fri Aug 08, 2014 12:59 pm
	Paul Baker wrote The change made to Sky High act 2 seems to be to do with the top row of tiles - on the v0 version, it is possible, using the hang glider from the start of the level, to go off the top of the screen. This causes you to lose the hang glider and fall. In v1, once you reach the top of the screen, you remain on-screen and keep the hang glider, merely being pushed against the "roof" of the level. This makes it hugely easier to reach the Chaos Emerald with the hang glider. I have been looking at this again and have found an interesting issue. If you jump from directly below the hang glider on Sky High act 2, then press left while it ascends, you are immediately teleported above the top of the screen. On v1, this can cause you to get stuck, apparently on top of the "roof". Also, the Game Gear version of Sky High act 2 matches Master System v0: It has no "roof".

dplc81 Joined: 20 Apr 2011 Posts: 33	Posted: Mon Sep 22, 2014 2:28 pm
dplc81 Joined: 20 Apr 2011 Posts: 33	I checked my Red labeled Tectoy Sonic 2 cartridge, and based on the SHZ2 roof and the spring on GMZ1 factors, I am the owner of a v2.2 version of the game! Is it rare?

dplc81 Joined: 20 Apr 2011 Posts: 33	Posted: Tue Sep 23, 2014 1:35 pm
dplc81 Joined: 20 Apr 2011 Posts: 33	Sorry for the double post, but I found some other relevant differences in Sky High 1 and 2. In the right down corner of the screen, in the 1.0 rom (or V0), there is a falling bridge (when falling off the glider) which was removed from version 2.2 (or V1). There is also a bug related to it, if you run the entire bridge and fall you will not die, being able to walk above the bottom of the screen. Jumping will cause you to lose rings/die as it normally works. The bug seems to affect the platform edges for the rest of the stage. Sonic will run in the air for a second and come back to the platform. This is notable on the platform where the glider is. Sky High Zone 2 has some layout differences as listed by Esrael (Neto) at Sega Brasil forums: http://www.sega-brasil.com.br/forum/viewtopic.php?f=1&t=4566&p=50989#p50... EDIT: added more information, reorganized post

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