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Namco System 2/Legend of Valkyrie problems

G

Grinning Cat

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Bit of a tale of woe this. Bought a Legend of Valkyrie from Japan nearly a year ago, and despite being pictured and described as being fine, I received a completely different PCB - with various patch wires (mainly around the sound section). And while it 'worked' - the game was always missing all the voice samples.

Originally, I was planning to just try and find something like a Cosmo Gang: The Video and just swap the ROMs on to that (given I had no idea what the problem was). Would also leave me with a mint board (which is what I thought I was getting to begin with). However, I couldn't really find much at a sane price. So, recently-ish, I sent it to a friend who's bailed me out with his awesome repair skills before.

He removed all the patch wires (which weren't doing anything, apparently) and after some troubleshooting, checking all the ROMs, etc, replaced one of the DACs (although sadly, that didn't solve the problem). After that, it became clear the culprit was (somewhat typically) the C140 custom.

The next bit is pretty bad...but I then bought a NOS Final Lap 3 (for no doubt far too much) - as I'd been told the top board of that was the same as the 'standard/typical' System 2 boards. Turns out, the top board is very slightly different - and won't work for love nor money ;( And it seems almost scarilege to start removing/transplanting customs from an NOS board (even to save a more valuable board like Valkyrie).

Obviously, going to have to have a major think as to what I do next (having poured far too much into this mess!).

But I guess I wanted to confirm:

- Are the top boards of Final Lap 3 and Legend of Valkyrie 100% incompatible? Seems pretty self evident at this point (neither board will post with the Valkyrie ROMs). But just thought I should check, just in case.

- Would all the standard System 2 games on this list https://www.system16.com/hardware.php?id=525 be totally compatible with my Valkyrie ROMs? My friend who's been doing the repair pointed out that even some of these boards appear to have minor physical differences. My Valkyrie has a socketed X68000 (whereas Super World Stadium '93 doesn't), for instance. But maybe that doesn't matter...

Any help much appreciated!
 
Can't answer your problem exactly, but system16 is a bad resource.

You'll want to look at the mame driver instead.

I'm on mobile or I'd snag the link for you, but Google for namco system 2 mame cpp and it should come up as a github link.

That should cover board compatibility.

Just to be sure though, you're moving the security chip over alongside the roms too, right?
 
Namco System 2 motherboard is the same among all games, it has identical layout (a socketed 68000 CPU doesn't mean the board is different...).The VIDEO board is, instead, different.There are three versions of VIDEO board but only one can be used for conversion.
 
caius said:
Namco System 2 motherboard is the same among all games, it has identical layout (a socketed 68000 CPU doesn't mean the board is different...).The VIDEO board is, instead, different.There are three versions of VIDEO board but only one can be used for conversion.
Click to expand...
Namco Final Lap 3 uses custom C68 @3D whist Valkyrie uses custom C65 @3D, which looks to be some kind of processor to control the inputs. Also there is extra TTL on Final Lap 3 around the sound RAM that Valkyrie doesn't have coupled with the different addressing circuit. It's also not listed on the conversion pcb list and probably why system 16 has labelled it as a Namco System 2 derivative. To an untrained eye it does look very similar indeed. I'm guessing to use a Final Lap 3 there's gonna be some rom patching required or loads of jumpers to fix the different address circuit. Maybe someone else can confirm this?
 
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Thanks everyone for all the help :) Did take a look at the github link (so this is all really helpful info for future reference).

And of course, massive thanks to Monstermug (who has been repairing this for me). And has had the patience of a saint throughout this whole debacle!

Looks like I really dropped the ball not checking here first (or on the github link) exactly which boards were compatible. I guess there are multiple morals to this story...but even apart from the obvious one about buying expensive PCBs from Japan via a proxy (with no comeback); I guess the second one, is that I probably shouldn't be choosing donor boards, period (at least not without asking for a lot more advice/supervision!).

It's looking like this is going to a full transplant job now...but will update, with more details (for anyone who's interested in how this pans out).
 
Like others stated there are two versions of the CPU board: one has a custom 65 which may or may not have a populated ROM next to the 65 chip. The later board has a custom 68 which does not have a ROM populated. Both boards should be interchangeable. This custom chip is mainly for analog IO on the driving games.

Just match up the ROM jumpers from your old Valkyrie to your Final Lap donor.

Try this before going to the trouble of desoldering chips.

(PS. Final Lap 1, 2 and Four Trax use the old custom 65 if you want to buy a matching donor)
 
I believe this issue can be fixed by installing a bat diode across 5G to remove the protection because it seems the layout of the alternative board calls for the protection key at a different location than the Valkyrie board. Since the video board is wildly different, the protection senses that the key is bad and final lap goes into constant reset whilst Valkyrie hangs at rom 3 check. This is usually a symptom of security checks on Namco System 2 boards.

I have checked this with mame and it does state:

"Again this board has a different graphics layout, also the protection checks
are done at $a00000 as opposed to $d00000 on a standard board. Similar
$a00000 checks have been seen on the Final Lap boards."

Looks like he got unlucky with this Final Lap Board.

Owner of the pcb would like to keep it as original as possible so it has been decided to do a transplant. It's no big deal to be honest. To be honest as a collector myself, I would have done the same thing. Also I am glad that he has decided to do this as I would rather replace the custom than do another bloody rom swap.
 
Shouldn't matter with Valkyrie. That is the one game that uses a fake key custom, meaning it does nothing other than the same thing that the bat42 diode trick would do.
 
Just out of curiosity, what would be the reason both games wont boot after a rom swap and jumper settings changed then. That was the only logical line of reasoning I could think off. Could it be that as the address is calling at a different location not even a fake key is being returned, hence the error?
 
I don't know. All I can say is that the game won't boot without either a key custom inserted on the video board, or the bat42 diode soldered in place. This is for the standard video board, not the final lap video board. The final lap video board has the key custom permanently attached. Not that it matters here. You don't care about playing Final Lap so just toss the Final Lap video board in your scrap bin.

Flip dip 1 and see if the game can get into test mode.
 
I think the problem is because I swapped the two pals over as well. Can't be asked to do another rom swap to find out though.
 
Just thought I update this post to for any other potential people with the same problem as grinning cat. I have confirmed it is possible to use a final lap. Just dont swap the pal over otherwise you will get addressing issues. Also if you have the "old" version roms for Valkyrie no Densetsu then you will be missing a few voice samples, noticeably the sound she makes when she shoots. Been chasing something that wasn't even broken in the first place.
 
Good to know. The PALs shouldn't have needed to have been swaped because only the key custom is supposed to provide protection on these boards. Namco actually sold ROM kits for System 2 back in the day, so regardless of what version board you have, it should have always been just a ROM swap only. I have a legit Burning Force and Dragon Saber boards. Dragon Saber uses the newer board like Final Lap 2/3. So don't think that newer board is limited to just Final Lap 2/3.
 
I'm not sure but I did end up swapping roms again and confirmed working by swapping one of the Pals. Putting pal back caused same issue.
 
Monstermug said:
Just thought I update this post to for any other potential people with the same problem as grinning cat. I have confirmed it is possible to use a final lap. Just dont swap the pal over otherwise you will get addressing issues. Also if you have the "old" version roms for Valkyrie no Densetsu then you will be missing a few voice samples, noticeably the sound she makes when she shoots. Been chasing something that wasn't even broken in the first place.
Click to expand...
hey mate, i've got a final lap 3 that i've converted to valk successfully bar the sfx (shooting voice sample etc). method was a video board + ROM swap, changed jumpers but PALs left alone
you mention the sound fx issues are because of "old" version ROMs, can you clarify if there a revision of the ROMs available that would fix the issue?

cheers & thanks to all in this thread, big help
 
The current version in mame is the new version. I dont think the old version has been dumped. If your getting this isse with the rom in mame let me know as the issue will be on the rom board.
 
I thought the old version of Legend of Valkyrie was just the sound ROM being written to the incorrect chip type ?
 
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