2600 Rom Comparisions and Dumps

[Rom Hunter]

Will do that.

 

[Rom Hunter]

Asked Christophero.

 

Demon Attack also contains the Imagic logo.

 

Ok, I think it's fair to say that these Activision logo ROMs are not old era.

 

What about that Title Match Pro Boxing?

 

Also, these weird Fast Eddie and Turmoil hacks are a mystery.

 

Did these two also come on a demo or Anthology disc?

 

[Rom Hunter]

Well, it's in your collection, so where did you get it from? What's the source?

No idea.

 

I've been collecting ROMs for more than ten years.

 

[Buzbard]

Yars' Revenge:

 

The shield changes color at higher levels. The color values for the shield are $32 (red), $06 (grey), $74 (blue), and $58 (purple/pink), loaded from $FFF3. The last value in [a] is $01 instead. Because bit7 makes no difference in the 2600's palette, this translates to BLACK! That would make for a pretty difficult game, because you would not be able to see the shield! There are 3 more bytes changed at $FFF7-$FFF9, but these are never read by either version (the index reading from the table is only allowed a range of 4 bytes).

 

;[!] version
LFFF3: .byte $32,$06,$74,$58,$00,$00,$00

;[a] version
;LFFF3: .byte $32,$06,$74,$01,$8B,$46,$F2

 

 

Bad dump? The manual says nothing about an invisible shield...and there's still no reason at all [a] should have 3 more garbage values.

 

I think I've found a source for the [a] version of Yars's Revenge.

I just remembered that I have this:

It has a 16k version of Yars' Revenge, I split that into 4-4k chunks and compared them to various other copies, the first 4k chunk is an exact copy of the [a] version, the other three chunks don't seem to match any of the other vesrions that are floating around.

Attached is that 16k version from the CD.YARS.zip

[+Omegamatrix]

I think I've found a source for the [a] version of Yars's Revenge.

 

I think you have too! Every 4k chunk has some garbage data in it. All of it is between $FFF6 and $FFF9, which is bankswitching hotspots for a F6 bankswitched game.

 

 

          Yars (original)    Yars.1    Yars.2    Yars.3    Yars.4
$FFF6          $58            $01        -         -         -
$FFF7          $00            $8B       $23        -         -
$FFF8          $00            $46        -        $8B        -
$FFF9          $00            $F2       $03       $1E       $14

 

It makes much more sense now. Actually I lied. It doesn't make sense at all, since there is no bankswitching going on. Having data screwed up at those particular places is not coincidental though. Especially since it totals 16K.

 

 

At least this version has been finally found (put to rest so to speak). Are all the games on that disk 16K? I'm betting if we looked at all the roms on there, more that were questionable in the past would be found. Also does Title Match Pro Wrestling have the Activision or Absolute logo?

[Buzbard]

Yes, they are all 16k.

ActionPack3.zip

 

Titlematch has the Absolute logo.

[+Omegamatrix]

Okay, I'm starting to see the pattern of trauma that was done to these poor roms. First of all the 2K roms are okay. Each part matches each other and the original. Starmaster is also good too.

 

Good roms (note roms are duplicated within 16K space)

2K - Breakout

2K - Canyon Bomber

2K - Checkers

2K - Combat

2K - Night Driver

2K - Space War

4K - Starmaster

 

So Pressure Cooker, Private Eye, Title Match Pro Wrestling, Double Dragon, and Yars' Revenge are left.

 

 

I split Private Eye into 4k rom chunks and found parts 1-3 correspond to the low bank in the original, and part 4 matches the high part. The important find was the garbage data matched Yars' garbage data!!!

 

          P.E. (original)    P.E. 1    P.E. 2    P.E. 3    P.E. 4 (2nd bank compared to part 4)
$FFF6          $00            $01        -         -         X
$FFF7          $00            $8B       $23        -         X
$FFF8          $FF            $46       $00       $8B        X
$FFF9          $FF            $F2       $03       $1E       $14 <<---at $1FF9 in part 4

 

Yars' Revenge Differences (note Yars.2 has $00 at $FFF8):

 

          Yars (original)    Yars.1    Yars.2    Yars.3    Yars.4
$FFF6          $58            $01        -         -         -
$FFF7          $00            $8B       $23        -         -
$FFF8          $00            $46        -        $8B        -
$FFF9          $00            $F2       $03       $1E       $14

 

If you join parts 1 and 4 of the 16K rom, you exactly match (in Rom's collection):

 

Private Eye (1983) (Activision, Bob Whitehead) (AG-034-04) [a].bin

 

I think it's obvious where this [a] version comes from now. It should be removed, why? Well look at the differences between the [a] version and the original:

 

        Original    [a]
$DFF6     $00       $01
$DFF7     $00       $8B
$DFF8     $FF       $46
$DFF9     $FF       $F2

$FFF9     $FF       $14
$FFFA     $03       $00   ; NMI    $F003 or $D000
$FFFB     $F0       $D0
$FFFC     $03       $00   : Reset
$FFFD     $F0       $D0
$FFFE     $03       $00   ; Break
$FFFF     $F0       $D0

 

Note: besides the garbage data at $DFF6, $DFF7, $FFF9, and ignoring the hotspots, the only difference is the vectors are all using $D0xx in the second bank. It doesn't match the rest of that bank at all. Nukey talked a bit about the [a] version of Private Eye here:

 

http://www.atariage.com/forums/topic/103737-2600-rom-comparisions-and-dumps/page__view__findpost__p__1605504

 

What Nukey is saying by superfluous is that instead of going to $F003, the code jumps to $F000 and the BIT instruction strobes $FFF9. Since we are already in Bank 1, no bankswitch occurs so the instruction is redundant. You see this often as space filler to line up both banks.

 

But what I am saying is that $D000 is not right because both Pressure Cooker and Title Match also seemed to be crapped out in the same way. This seems to be an artifact of this Activision collection, and not a deliberate programming choice. I'll talk more about that later. This post is already too long.

[+Omegamatrix]

Alright onto Double Dragon. Having recently done a rough disassembly of Double Dragon (to convert it to use Genesis controller), I know the origin of the banks are such:

 

 

bank 0: $9000

bank 1: $B000

bank 2: $D000

bank 3: $F000

 

Nothing to special there. Most 16k games are similar. The comparison though shows how screwed up it is:

        Original    [a]
$9FF6     $EA       $0A
$9FF7     $EA       $0A
$9FF8     $EA       $0A
$9FF9     $EA       $0A

$BFF7     $EA       $0A
$BFF8     $EA       $1D
$BFF9     $EA       $1D
$BFFD     $B0       $90
$BFFF     $B0       $90

$DFF8     $EA       $4D
$DFF9     $EA       $4D
$DFFD     $D0       $B0
$DFFF     $D0       $B0

$FFF9     $EA       $4D
$FFFD     $F0       $D0
$FFFF     $F0       $D0

 

Yeah, it's messed. A few points to make here:

 

- It's PAL, not NTSC.

- It (the dump off of the Activision collection), 100% matches this dump that was removed here, now we know where that dump came from!!

 

Double Dragon (1989) (Activision, Dan Kitchen) (EAK-050-04) (PAL) [a]

 

http://www.atariage.com/forums/topic/103737-2600-rom-comparisions-and-dumps/page__view__findpost__p__1602904

 

- I'd like to point out the $D0xx are occurring in the last bank. This will be similar in upcoming comparisons, and is also similar to what happened in Private Eye!

- There are an abundance of $0A that seem to be replacing NOP's in the hotspots. This will also be similar later...

 

 

So in summary, this was another questionable rom. It has already been removed from Rom's collection, but we now know the source. I have no idea what was happening with this dumps to make them like they are, but I can see the patterns.

[+Omegamatrix]

I split Title Match Pro Wrestling into 4K chunks like I did with Private Eye. Like Private Eye, parts 1-3 correspond to bank 0, and part 4 corresponds to bank 1.

 

 

          T.M. (original)    T.M. 1    T.M. 2    T.M. 3
$FFF6          $F5            $0A        -         -
$FFF7          $FF            $0A       $0A        -
$FFF8          $EA            $0A       $0A       $0A
$FFF9          $EA            $0A       $0A       $0A

 

This is all comparisons of the low bank, bank 0. Here we can see that $0A is once again being replacing $EA (quite a bit). Also note that with each bank increase in the 16K version, it gets closer the original (less differences). You might have noticed the similar upper triangle in Yars' and Private Eye.

 

 

Now lets look at bank 1, the upper bank:

 

          T.M. (original)    T.M. 4
$FFF9          $EA            $0A
$FFFB          $F0            $D0
$FFFD          $F0            $D0
$FFFF          $F0            $D0

 

Once again, the NOP at that hotspot has changed to $0A, and the vectors in the last bank are $D0xx, when the should be $F0xx.

 

 

I should also point out here that $D0xx and $F0xx are the same to the 2600, but we're looking at rom critically here, and we're trying to make a judgment as to whether the dump is true or not. Now the icing on the cake is combing parts 1 and 4 (just like we did with Private Eye), gives us another exact match to an alternate rom:

 

Title Match Pro Wrestling (1987) (Absolute Entertainment, Alex DeMeo) (AG-041-04) [a].bin

 

http://www.atariage.com/forums/topic/103737-2600-rom-comparisions-and-dumps/page__view__findpost__p__1606802

 

It was removed, and rightfully so! This PC compilation has caused quite a few [a] versions it seems. I'm betting more [a] versions were caused on the other PC Activsion compilations too.

 

A couple of more points on TMPW:

 

- Nukey noted that Title Match Pro Wrestling - Pro Wrestling (PAL) Differing hotspot values. The [a]lternate here is suspected to be correct ONLY because of the NOP value used ($EA...which the NTSC game above did).

From what I see, I agree with him. However after seeing what caused the NTSC alternate, I believe the PAL [a] should have stayed in the collection. Don't confuse the PAL/NTSC versions here, because now I am talking about the PAL rom... I believe the PAL [a] should have stayed, and that the old PAL version should have been removed. I think I might still have one that I can dump and double check in a few weeks from now.

 

- There is no Activision logo in any part of the 16k rom.

 

It also seems apparent at this point that whoever dumped these PC versions originally, split the roms and rejoined them manually.

[+Omegamatrix]

Alright, we're down to our final game, Pressure Cooker!!

 

 

I noticed that just like Private Eye, Double Dragon, Yars' Revenge, and TMPW, Pressure Cooker has differences at $xFF9. This would be a hotspot in a F6 game. I just found it odd that in the last bank of these 16k roms, the vectors seem to all be $D0xx, and $FFF9 (but not $FFF6 - $FFF8) always seems to be always messed.

 

 

Here is the low bank. Note that parts 1 and 3 exactly matched the original rom, so they are not listed.

          P.C. (original)    P.C. 2
$DFF7          $00            $FF
$DFF8          $00            $FF
$DFF9          $00            $FF

 

$DFF7 is not a hotspot, but it is not read correctly none the less.

 

 

With the upper bank:

          P.C. (original)    P.C. 4
$FFF9          $00            $FF
$FFFD          $F0            $D0
$FFFF          $F0            $D0

 

We see that $D0xx has returned, and $FFF9 is messed. $FFF9 might be messed because it would be a hotspot on a F8 game, but you should be able to read it correctly if you are in bank 1. Makes little sense to me. Anyhow big thank you to Buzbard. You're the man for helping solve some of these [a] roms.

[Rom Hunter]

Good job, Omega.

 

Correct me if I'm wrong, but AFAIK all these [a] versions were already removed from my collection, right?

 

I can't find them in my v6 collection anymore.

 

Also, you're saying that Title Match Pro Wrestling PAL [a] from the old collection should be put back in the V6 and that the PAL one currently in the V6 should be removed?

 

Also, there are not much [a] versions left from Atari and the big third party companies.

 

Perhaps these should be checked too to see if there are any PC version patterns.

 

Edited April 21, 2010 by Rom Hunter

[+Omegamatrix]

Remove this rom from your current collection:

 

Private Eye (1983) (Activision, Bob Whitehead) (AG-034-04) [a].bin

 

Also, you're saying that Title Match Pro Wrestling PAL [a] from the old collection should be put back in the V6 and that the PAL one currently in the V6 should be removed?

 

That's right. I was looking back at version 2 if that helps. And yeah, it was the PAL roms I was saying should be switched.

[Rom Hunter]

So this one is the correct ROM:

Title Match Pro Wrestling - Pro Wrestling (1987) (Absolute Entertainment, Alex DeMeo) (EAZ-041-04I) (PAL).bin

 

Right?

 

[+Omegamatrix]

Yes, that is right. I matched the rom you posted in HOM3.

 

 

I should say here that the difference between the roms is just at the hotspots. I feel that this version is better dump as the hotspots match the NTSC version, and even the butchered PC version looked like it was trying to use NOP's at the hotspots (although it had most of them replaced with $0A).

 

 

I'll check in a couple of weeks to see if I still have my PAL Titlematch. If I do I'll give it a dump.

[Buzbard]

Ok guys, I have one more Atari collection CD.

 

It's "Atari 80 Classic Games In One"

 

It has 5 roms that Stella doesn't seem to recognize during an audit.

ROMs.zip

 

Every other rom on the CD is recognized as good roms except 2 which are:

 

Super Breakout (1982 - 1981) (Atari) [a].BIN

SwordQuest - EarthWorld (1982) (Atari) [a].BIN

 

which could be the source for those 2.

 

I also have "Atari Classics Evolved" for the PSP but I can't seem to find those roms, their probably compressed or encoded using some technique that I'm not familiar with.

[Rom Hunter]

Thanks!

 

Damn, looks like these retro ROMs are everywhere.

 

[Rom Hunter]

Let's wait and see what Omega has to say about these two.

 

[+Omegamatrix]

I'll take a look at these. Buzbard even though Stella recognizes the roms, I would like to examine all the roms on that disc if I can. Would you be able to post or send them to me?

 

 

@Rom, I'm thinking eventually all the discs out there are going to have to be checked. There's just no choice. Private Eye [a] would have stayed in your collection if we had never found it on there. I think the best way to go for legit alternates if finding at least 1 physical cartridge that they are on. I'll start going through my collection in a couple of weeks. I also might hit up some thrifts and pawn shops to see if I can find a few of the remaining compilations on the cheap.

[+stephena]

I'll take a look at these. Buzbard even though Stella recognizes the roms, I would like to examine all the roms on that disc if I can. Would you be able to post or send them to me?

 

 

@Rom, I'm thinking eventually all the discs out there are going to have to be checked. There's just no choice. Private Eye [a] would have stayed in your collection if we had never found it on there. I think the best way to go for legit alternates if finding at least 1 physical cartridge that they are on. I'll start going through my collection in a couple of weeks. I also might hit up some thrifts and pawn shops to see if I can find a few of the remaining compilations on the cheap.

I don't know if it's been mentioned, but the Private Eye ROM labeled '[a]' is handled as a special case in Stella. Normally, F8 ROMs start up in bank the last bank (aka, bank 1). However, this ROM doesn't work unless started from bank 0. You can see this when pressing 'Alt l', where the bankswitch type is listed as 'F8 swapped'. This isn't a real bankswitch scheme, and it can't be set in the ROM properties. Originally, the only Private Eye ROM I had access to was the [a] version, and it wasn't labeled that way originally. Thinking that this was the only valid dump, I added the special case to Stella. Now that's it's labeled as [a], perhaps when you remove it from the collection I'll get rid of that 'F8 swapped' logic completely.

[Buzbard]

I'll take a look at these. Buzbard even though Stella recognizes the roms, I would like to examine all the roms on that disc if I can. Would you be able to post or send them to me?

 

No problem, PM sent.

[+Omegamatrix]

I did notice the F8 swapped, but I didn't realize you had built a special scheme for this. It's nice that as Rom's collection gets cleaner so does Stella!

 

 

@Buzbard I got them, much appreciated for all your help! I'll take a look but it might take me a couple of days. I'm going out for drinks later on tonight.

[Buzbard]

They must be some pretty good drinks, if you're gonna be out for a couple days! j/k

 

No problem, take your time. Meanwhile I'm gonna work on the Atari Classics Evolved set to see if I can figure it out.

[Rom Hunter]

Many thanks, guys.

 

I'll wait with the release of V6 until everything is sorted out correctly.

 

[Wickeycolumbus]

Many thanks, guys.

 

I'll wait with the release of V6 until everything is sorted out correctly.

 

 

You may want to wait a bit longer, I'm expecting something new in the next week or so

[+Omegamatrix]

You may want to wait a bit longer, I'm expecting something new in the next week or so

I had my eye on something on Ebay too. Not sure if you got what I was thinking of, but I hope so.