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Jaleco Big Striker to Cybattler, Chimera Beast, or 64th Street Detective

twistedsymphony

twistedsymphony

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I've done my first conversion patch! and I'm pretty stoked. I'm sure this is a joke compared to the titans around these forums that have cracked some hard games wide open, but I've been trying to get my feet wet with this stuff for a while so this is a big step even if it was an extremely simple patch :) The pointers for using the MAME debugger that you guys have given me really helped and a big thanks to Hammy who suggested I look at the memory map when I got stuck in a situation where it worked in MAME but not on the hardware :)

41720634_324841698290431_1369112394390454304_n.jpg

It uses a Big Striker Donor PCB use the ROMs from MAME but replace ROM #2 with a patched file I created.

All of the EPROMs are socketed but the sprite priority PROM (ROM [12]/IC155) will need to be de-soldered. These N82S131N are also tricky ICs to find and even harder to find a programmer for. I bought some of these: https://www.etsy.com/listing/244633763/4-x-82s12682s12982s131-bi-polar-prom per Darksoft's suggestion and they work perfectly

I'll be looking into that further this weekend and also see if I can patch Chimera Beast and 64th Street as well. I'll post my results here.


Thank you to Hammy for testing out Chimera Beast on actual hardware for me :)
Thank you to TheDeath for testing out 64th Street on actual hardware for me :)
 
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A lot of those PROM chips can be replaced with a GAL but you need someone to do the calculations

Good work on the conversion, I have an original Cybattler here at the moment I'm trying to fix for someone and it's a cool game.
 
I had a few minutes to spare tonight so I assembled and installed one of those bi-polar rom adapters from etsy and it works fantastic. A little ugly but it works.

20180928_183455-1024x576.jpg
 
Out of interest, if you remove that PROM or the incorrect one is installed, what happens?

I'm repairing an original Cybattler and it's got sprite issues. ROMs, RAM and associated logic has all tested ok, so I'm wondering if this PROM has gone bad.
 
the proms on all of the mega system 1 games are just used for sprite priority. So you can use the wrong one but some sprites get displayed in the wrong depth order on the screen.

Using the big striker prom on cybattler just had some of the background objects blocking your view but otherwise fully playable.
 
twistedsymphony said:
I've done my first conversion patch! and I'm pretty stoked. I'm sure this is a joke compared to the titans around these forums that have cracked some hard games wide open, but I've been trying to get my feet wet with this stuff for a while so this is a big step even if it was an extremely simple patch :) The pointers for using the MAME debugger that you guys have given me really helped and a big thanks to Hammy who suggested I look at the memory map when I got stuck in a situation where it worked in MAME but not on the hardware :)

41720634_324841698290431_1369112394390454304_n.jpg

For those of you interested it uses a Big Striker Donor PCB use the ROMs from MAME but replace ROM #2 with this patched file I created: http://www.filedropper.com/bs2cb

All of the EPROMs are socketed but the sprite priority PROM (IC22) will need to be de-soldered. These N82S131N are also tricky ICs to find and even harder to find a programmer for. I still need to swap mine. but I bought some of these: https://www.etsy.com/listing/244633763/4-x-82s12682s12982s131-bi-polar-prom per Darksoft's suggestion.


It also seems that it might be possible to replace them with a GAL: http://elgensrepairs.blogspot.com/2014/03/using-gals-to-replace-small-sparse.html


I'll be looking into that further this weekend and also see if I can patch Chimera Beast and 64th Street as well. I'll post my results here.
Click to expand...
Congrats on your first patch!
I hope this encourages you to keep practising.
 
Apocalypse said:
Congrats on your first patch!I hope this encourages you to keep practising.
Click to expand...
Thank you :) it absolutely has encouraged me to keep going. I already have some ideas on the next games I want to try... now it's about finding the time to fit this in :)
 
I've got both Chimera Beast and 64th Street patched and working in MAME for use on a Big Striker PCB. I'm waiting for some more EPROMs to arrive before I can test them out on actual hardware.

If anyone else has a Big Striker and wants to test it out let me know and I'll send you the files. I don't want to post them up until I've had a chance to test though.
 
Now make a multi to switch between the 4 games and send me a kit :)

Jaleco MS1 has some cool games, too bad it has like 4 different revisions to it with different cpu, sound, etc..

@Apocalypse You think the games could be patched to run on one revision of the hardware, it not all most of the good games on the system?
 
Derick2k said:
Now make a multi to switch between the 4 games
Click to expand...
I've already started thinking about it :D

As for porting other games there are 5 hardware versions for Mega System 1:
Z - only has one game and uses a different sound CPU so it's probably stuck on it's own (unless there is a way to port Z80 code to 68000? Seems like it'd be A LOT of work if it's even possible)

A - the most common and has the most games, and uses a ROM board for the games, a prime candidate for a multi but has the weakest hardware aside from the Z-version so will probably only ever play A-version games.

B - Half way between the A and C hardware in terms of specs, some of these games might port to the C hardware, but I haven't looked too far into it. really only 2 games worth playing here though: Avenging Spirit and Earth Defense Force. both games are also available on the A-Version hardware too, so...

C - The most powerful of all the hardware versions runs Big Striker, Cybattler, Chimera Beast and 64th Street.

D - only has one game (PeekaBoo) but is similar to a stripped down C-version hardware, memory map is different and the game uses spinners so even if it's ported and running there might be issues with the controls.

I think best case scenario would be two multis: an A-Version multi and a C-Version multi (with B, C and D games) and Legend of Makai on the Z-Version hardware would be stuck on it's lonesome.


I'm open to advice from people who have ported games to different platforms where memory maps were different. It's a bit above my head at the moment but I'd interested in learning/figuring it out :D
 
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Copied some info over from VGMRips to have as a reference


MegaSystem1Logo.png


Main CPU:
  • Mega System 1-A/Z: Motorola 68000 @ 6 MHz
  • Mega System 1-B/D: Motorola 68000 @ 8 Mhz
  • Mega System 1-C: Motorola 68000 @ 12 Mhz
Sound CPU:
  • Mega System 1-A/B/C: Motorola 68000 @ 7 MHz
  • Mega System 1-Z: Zilog Z80 @ 3 MHz
Sound Chips:
  • Mega System 1-A/B/C: Yamaha YM2151 @ 3.5 MHz + 2xOKIM6295 @ 4 MHz (Hayaoshi Quiz Ouza Ketteisen happens to have the OKIM6295 chips clocked at 2 MHz instead)
  • Mega System 1-D: OKIM6295 @ 2 MHz
  • Mega System 1-Z: Yamaha YM2203 @ 1.5 MHz

Game NameSystem Type
P-47: The Phantom Fighter / Japan P-47: The Freedom FighterMega System 1-A
Kick OffMega System 1-A
Samurai-Fighter Shingen / Japan Takeda ShingenMega System 1-A
Ninja Kazan / Japan Iga Ninjutsuden: Goshin no ShoMega System 1-A
Tenseiryu: Saint DragonMega System 1-A
Plus AlphaMega System 1-A
Jitsuryoku!! Pro YakyuuMega System 1-A
Hachoo!Mega System 1-A
The Astyanax / Japan The Lord of KingMega System 1-A
Rod Land / Japan Yousei Monogatari Rod LandMega System 1-A
Avenging SpiritMega System 1-A
SoldamMega System 1-A
E.D.F.: Earth Defense ForceMega System 1-B
Phantasm (Japan rel of Avenging Spirit)Mega System 1-B
Hayaoshi Quiz Ouza KetteisenMega System 1-B
64th. Street: A Detective StoryMega System 1-C
Big StrikerMega System 1-C
CybattlerMega System 1-C
Chimera BeastMega System 1-C
Peek-a-Boo!Mega System 1-D
Legend of Makai / Japan Makai DensetsuMega System 1-Z
 
Derick2k said:
Now make a multi to switch between the 4 games and send me a kit :)

Jaleco MS1 has some cool games, too bad it has like 4 different revisions to it with different cpu, sound, etc..

@Apocalypse You think the games could be patched to run on one revision of the hardware, it not all most of the good games on the system?
Click to expand...
Between A/B/C/D maybe.
Converting Z games should be considered unfeasible without a ton of efforts (different sound hardware).
 
Hammy was nice enough to test out my Chimera Beast conversion and confirm that it runs on actual hardware.

I've posted the patched files for Chimera Beast and 64th Street A Detective Story in the first post.

So I guess now I start learning how to route a PCB to make a 4-in-1 Multi :P
 
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