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August 15, 2017 Haze Categories: General News. 22 Comments on TH Strikes Back is now WORKING

We picked up 2 more TH Strikes Back PCBs (thanks to Kevin Eshbach for providing one of them) and dumped the DS5002FP SRAM on each of them.

Using the existing read, and these 2 new reads we were able to apply a ‘majority wins’ rule on each byte and obtain a correct dump. (about 5 or 6 bytes differed from each board but never the same bytes)

These bytes have all been hand verified, so now I’m confident we now have a 100% good dump of the DS5002FP SRAM for TH Strikes Back (Thunder Hoop 2) as a result the game works fine in MAME (aside from some video priority glitches on the title screen but these are unrelated to the protection)

Note, we still need another PROTECTED (not converted to de-suicide ROMS) Alligator Hunt to verify the dump we did of that before releasing it and at least one additional Target Hits (we only have 1 copy) before we can confidently release that also. It’s fairly clear at this point that random bytes get corrupted during the process, so without multiple copies to dump we can’t trust the data.

Also the call still goes out for anybody with a working Play 2000, ideally 2 people.

It’s easy enough to tell if you have an Alligator Hunt where the battery still works as the protected sets will save the Top 2 high scores to the SRAM so those scores are retained even after powering down the PCB. The desuicide sets have nowhere to save it so the top 2 scores reset to default when you power off. We need another working copy of the protected version (ie the one that saves the top 2 scores)

The other way to identify the protected version is if it shows ‘CHKSUM ROM: 2B34128B’ on startup, these boards are useful to us.

A board that’s already been hacked to not use the battery will show ‘CHKSUM ROM: F9C6891D’ instead, such boards are useless to us as the SRAM on them is already dead.

There are no known unprotected versions of Target Hits or of Play 2000, so if you have either of those in working condition we could do with them.

We currently have a number of Glass boards, and hopefully 2 Maniac Square boards and will tackle those soon.

Please note that once we have reads we’re happy with they can be used to repair dead boards, but we don’t want to release dumps until we’re confident about them as there becomes a risk of people trying to repair boards with bad data, making it more difficult to obtain the PCBs we need to verify it.

Here’s a video of TH Strikes Back


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TH Strikes Back
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TH Strikes Back TH Strikes Back

22 Comments

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Great news, amazing work yet again by the Galeco dumping team.

awesome!! Great work, guys!!

Muito obrigado! :)

Thanks from Spain for your hard work to preserve this piece of arcade history!!

Thanks for your super work, i played this game years ago. Keep preserving this jewels ;)

Thanks!!! A nother game is sealed.

Always look forward on progress about MAME

THANKS FROM THE DEEPEST OF MY HEART!

Amazing work!
Thank you Haze and the dumping team :)

“Non suicide game, no need to change battery”
That one has already been hacked, it’s useless to us.

We need one running the original code, where the battery still works.

Most have already been hacked like this one sadly. Hacked ones have no value, they’re basically bootlegs.

Ok Haze.

But the hacked game is already in mame?

Right, and we want to emulate the original protected version. We can’t dump the original protection code from a board that’s already been hacked to not use the battery because on those boards the SRAM containing said code is already dead.

Just because there’s a version in MAME that is playable doesn’t mean there isn’t work to do. It isn’t simply about playing games, it never has been.

Amazing work!
Thanks from Italy

http://www.neo-arcadia.com/forum/viewtopic.php?t=58495
So many reasons why is not cheap to dump. Cave Dev. are Wierdos. Waiting for degica port on steam.

Hi Haze,

Nice work there!!!

I have an Alligator Hunt pcb same as you specify above.
The board boots with the co-processor error but work perfectly aparently
Was tested my self today, 2 players playing and we dind’t noticed nothing wrong in the game.
I’m not really sure what kind of error gives this game when the sdram dies, but i probed the battery next to the Dallas protection and give me 3.03 volts.
Assuming that, maybee this is the pcb you are looking for.
Check pictures below i made 4 u!

[url=https://postimg.org/image/a2lsaumun/][img]https://s19.postimg.org/a2lsaumun/20170828_195300.jpg[/img][/url]

[url=https://postimg.org/image/oabgzhzjj/][img]https://s19.postimg.org/oabgzhzjj/20170828_195852.jpg[/img][/url]

Hi Haze,

Nice work there!!!

I have an Alligator Hunt pcb same as you specify above.
The board boots with the co-processor error but work perfectly aparently
Was tested my self today, 2 players playing and we dind’t noticed nothing wrong in the game.
I’m not really sure what kind of error gives this game when the sdram dies, but i probed the battery next to the Dallas protection and give me 3.03 volts.
Assuming that, maybee this is the pcb you are looking for.
Check pictures below i made 4 u!

Jorge Silva>

Alligator Hunt is a bit different to the other Gaelco games, they do a Checksum of the data area, and will print ‘CoProcessor NOT READY’ if that checksum doesn’t match rather than only when the coprocessor is completely dead.

Obviously your Co-Processor is still ‘working’ to some degree as the game is playable. (so the code is OK, just the data is slightly corrupted)

However, some enemy spawn locations / types might be wrong on your PCB due to the corrupt data, although it would be very difficult to notice it.

The good news is that we’ve managed to find a working PCB and now have a good dump of the SRAM, the original dump has been verified, data table is verified etc. so we have what we need :-)

Good news Haze!
I was trying to be hopeful to help on this matters!
I was used to be an contributor on MAME once with Power Flipper Pinball Shooting.
I’m glad to know that you found a full working board to (demystify) confirm the first dump.
Following your theory my board is not working correctly, and now i will have a way to fix it at least!
Thanks again for your awesome work on MAME team.
Regards from PORTUGAL

Great job,guys! Thank you very much for making this game work for MAME.Played TH Strikes Back a long time ago as a teenager but i never got very far into the game.So nice to see this classic finally working on MAME.

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