Debug for NeoCD

NeoTurfMasta

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Also, are there any clean hi-res overhead shots of the main PCBs for these? Front/top loader would be nice in particular since I am assuming that the oldest model would be the least consolidated/easiest to identify individual components. Anything would be cool though.

I can get you pics probably tomorrow of all three.

New BIOS tests will commence in a few hours.

EDIT: Sorry forgot to add info about the memory. The empty spaces are marked with '514400' I put in Toshiba brand of the same number. Looks like they are 1Mx4 (4M), so that should equal another 6MB of DRAM, right? So I assume it is essentially doubling the amount of DRAM on board. I think.
 
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NeoTurfMasta

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-neocdregular is the same thing as before but ironed out a bit with a few changes, if it still resets, try the below ones.
-neoregdump should display a few numbers on screen. If this doesn't work, I have to pick apart the boot process.
-neonocnt has disabled input, removes a few variables from the problem

neocdregular: Same resetting problem after initial load

neoregdump: These numbers appear after initial load
0000B000 00100000
FFFFFFFF 00FF0000
00000001 00FF0090
00000045 00111C12
0000004B 00102800
00001224 00108000
00000028 00102480
0000FFFF 0010F2FC

I didnt do the 3rd one yet, I only have 3 compatible eproms that I swap with and I always keep one with the original bios just to make sure things are 100%. If you need me to do the 3rd, let me know.
 
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smkdan

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Alright, if neoregdump works then there's nothing bizarre about the CDZ stopping this from working. I just messed up somewhere that upsets the real machine but emulators let it slide. neoregdump numbers look perfectly fine..

The third one and second one would help if neocdregular keeps resetting. If it's not too much trouble then the third one working/not working will narrow down the reasons it doesn't work. I'll be looking over my program in the mean time incase I missed something that real CDZ probably doesn't like.

edit: yeah your CDZ has 105.5megs in cart terms now, if I added the numbers right (57.5 + 48). Just have to see what RAM got allocated to what in later tests..
 
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NeoTurfMasta

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The third one and second one would help if neocdregular keeps resetting. If it's not too much trouble then the third one working/not working will narrow down the reasons it doesn't work. I'll be looking over my program in the mean time incase I missed something that real CDZ probably doesn't like.
Just tried the 3rd one and it also resets after the initial load.

edit: yeah your CDZ has 105.5megs in cart terms now, if I added the numbers right (57.5 + 48). Just have to see what RAM got allocated to what in later tests..

GIGASHOCK! Hahaha, guess not.
 

smkdan

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Just tried the 3rd one and it also resets after the initial load.

This one sidesteps the most likely thing causing the reset. It's tackier but it's simpler and less stuff to go wrong. I was relying on stuff I have to guess the function of by looking at what the BIOS does, didn't pay off. Hoping that one works, it should work if neoregdump did.

GIGASHOCK! Hahaha, guess not.

I never imagined SNK would make the CD system expandable like that. I heard of people upgrading RAM in Xbox consoles but never thought I'd see it in a console of this time. I'll try taking advantage of extra RAM for when this issue is out of the way.
 

SNKNostalgia

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It seems like the extra ram was planned in the first place. I bet they were going to do something like what some Super CDRom 2 games did if you used an Arcade Card for the PC Engine systems. Pop in KOF 96 in your toploader, it loads between rounds, but in your CDZ that has twice the RAM all characters load. This really would have been a good move on SNKs part. Still, the CDZ was a $400 system when it came out while the Toploader was $300. In that case, it would have been maybe $450 or so. I guess SNK felt it wasn't worth the trouble, but I think it would have been.
 

NeoTurfMasta

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This one sidesteps the most likely thing causing the reset. It's tackier but it's simpler and less stuff to go wrong. I was relying on stuff I have to guess the function of by looking at what the BIOS does, didn't pay off. Hoping that one works, it should work if neoregdump did.

WE ARE NOW WORKING! Region/Dip screen appears, region mode works perfect too. Need to try some dips on various games.
 
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It seems like the extra ram was planned in the first place. I bet they were going to do something like what some Super CDRom 2 games did if you used an Arcade Card for the PC Engine systems. Pop in KOF 96 in your toploader, it loads between rounds, but in your CDZ that has twice the RAM all characters load. This really would have been a good move on SNKs part. Still, the CDZ was a $400 system when it came out while the Toploader was $300. In that case, it would have been maybe $450 or so. I guess SNK felt it wasn't worth the trouble, but I think it would have been.

4 meg of ram in the end of 1995 / beginning 1996 would set you back in at least a hundred. getting the system to 500+ price point.

You have to think it was a short term cash cow for SNK as it was all going to be replaced by their next gen hardware the hyper 64.
 

smkdan

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cool, nice to hear CDZ confirmation that it works. I'll have a look a soft dip settings in a separate page soon along with a way to pull up the menu mid-game. Looking at the slug 1 CD program, all the stuff is there as it was from MVS as expected.
 

SNKorSWM

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4 meg of ram in the end of 1995 / beginning 1996 would set you back in at least a hundred. getting the system to 500+ price point.

You have to think it was a short term cash cow for SNK as it was all going to be replaced by their next gen hardware the hyper 64.

IIRC the expansion RAM cart of Sega Saturn was 4 megs, released at about that time and not anywhere close to 100.

ed: With X-Men and Street Fighter bundled together, the MSRP was 7800 yen, considering that the rate of dollar to yen was about 1:110 at the time. The cost for the entire bundle would be ablut $70.
 
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IIRC the expansion RAM cart of Sega Saturn was 4 megs, released at about that time and not anywhere close to 100.

by the mids of 1996 ram was half of the price that was 6 months prior and by the end of 1996, 1/4.

Everyone did ram upgrades to run windows 95 well

:loco:
 

systmdfect

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by the mids of 1996 ram was half of the price that was 6 months prior and by the end of 1996, 1/4.

Everyone did ram upgrades to run windows 95 well

:loco:

Ram seemed to start decreasing substantially from that point up until last year. Hell, I remember when a 64 meg ram chip for my gateway tower was over $100. Now you can pick up 1 gb of value ram for about $20. I'm already starting to feel old and I'm only 24, sigh...
 

Razoola

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In relation to the new RAM, its not going to be as simple as it sounds to get more stuff loaded. Firstly youll need to know what that new ram is attached to (Program or GFX). If its program then games will need patching to take into account using the new region. If its GFX then games will need alot of patching to use it. In effect you will need hacked games to use but some MVS games could be converted to CD to use it but not all probably.
 

Deuce

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If I can spare some cash once rent is taken out of the next paycheck, I will toss a few bucks toward this, as well. Nice to see you still plugging away at Neo hardware, smkdan. :D
 

smkdan

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Yes there is a lot of work involved in getting games to use the extra RAM. It might be a bit much for a softpatch (you won't need to burn a new disc) but it totally depends on how the game uses the extra space. It's a ton of work anyway, if only 1 guy is optimizing neocd games then not much might come of it honestly. Whenever I get around to buying a CDZ, it'll just be me playing games and finding what pisses me off the most, then fix that. It's what motivated the SS3 fix anyway.

For updates: 99% of soft DIP stuff is in my notes now, CD games implement it fully it seems. Even SSRPG has MVS compatible soft dip tables although the settings look pretty odd for what it is. For some games it's kind of redundant, but I'll get soft dip for each game autoloading at reset. With an 8KB memcard it should be able to hold plenty of extra slots but obviously it will be optional.

Also seeing a bit in detail how BIOS talks to drive controller, the loop where it loads each sector of disc then moves it to given region of RAM is pretty clear now, but lots of details missing. The way it's implemented is kind of obtuse though and might complicate any changes. anyway I'm up for coding replacement drive I/O if it gets that far.

@Deuce: yeah I'll stick around for a bit, there's still a whole lot of stuff I want to do with neo but I'll save that for later.

@EvilEvo: as of now, nothing done for load times. Not ruling it out though. CD does have the MVS configuration it just forces a default setting based on the current region. MVS mode is possible but extra work is needed to insert coins, fix credit counter etc.
 

smkdan

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yeah Raz was right about soft DIPs, very simple to pick up. I cloned it without any dramas it seems to display fine.

Interesting. What are these mysterious settings?

Here's SSRPG and some others I tested with:
ms2.PNG
pulstar.PNG
SSRPG.PNG

Nothing of any real interest, not sure if they are even used but they look a bit strange for an RPG.

It's called "RPG GAME" something in Japan region, test program elsewhere.
 

Razoola

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Also seeing a bit in detail how BIOS talks to drive controller, the loop where it loads each sector of disc then moves it to given region of RAM is pretty clear now, but lots of details missing. The way it's implemented is kind of obtuse though and might complicate any changes. anyway I'm up for coding replacement drive I/O if it gets that far.

I have looked at this code in the past and it can be optimised very easily, its just a case of if the code will be to fast for the hardware to handle. Sort of the same problem that affects the MVS when overclocking the cpu, ports for writing to GFX RAM are not able to keep up.

Raz
 

Takumaji

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Wow... just... wow.

Can't wait to give it a try on my standard top loader!

Great work guys, keep it up!
 

Dio Brando

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I discovered this through the other thread you made, NeoTurfMasta. Thanks for bringing awareness for such an amazing project, or else I (and probably many others) would have never been aware of it. I personally do not own a NGCD, but this is still pretty exciting.

Great work, everybody! Way to help bring new potential for the NGCD.
 

Hewitson

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Wow.. Incredible work smkdan, I've cracked a few Amiga games but I can't even begin to imagine how you or Raz pull this stuff off.

Personally I wouldnt have wasted my time on the CD systems but your efforts are very impressive.
 
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