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Ridge Racer System 22 repairs...

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rotunda View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rotunda Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 1:59pm
Quote Namco uk Never had a Test Rig, it was just a wiring harness so that could test it on a bench, they told me this when I sent them my RR pcb for repair

I was told similar but they had a main diagnostics machine which the harness went into and from what they told me even this machine is gone which would effect System 1, 21, 22 and so on. 

Quote Yeah, I was thinking any ‘test rig’ just simplified the diagnosis of which chip has failed, which people can often work out by other means.
The issue is the lack of a bucket of spare custom ICs.

True, perhaps my thoughts are a little drastic in the past post but i know Namco had to use this machine to diagnose faults otherwise it was a huge guessing game. Faults can be custom IC's, GPU RAM failure, traces worn out, the via's are also prone to failure. You also have 4 board to work with the primary CPU, primary GPU, custom ROM board and the second GPU board so fault finding without that diagnostic equipment would be a pretty long job.

Quote @rotunda - there is a rave racer at the timewarp arcade in bridgewater, which is in the south west :)

They sure do! I know the owner of the arcade and I've set many Rave Racer Twin Galaxies records on that very machine.

Quote Can someone explain this:

The reason that the boards are hard to repair etc. is that the chips are custom namco ICs right?

Ridge Racer is currently working emulated isn't it?

Does that not mean that we must know what the custom ICs do, and could just remake on in an FPGA?

Very interesting point... I'm not too clued up on emulation apart from actually running MAME but if you are right... that would be amazing!! I think i heard that the custom IC's are encrypted though so that is why replicating them is very hard.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote John Bennett Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 2:02pm
Originally posted by bobbydilley bobbydilley wrote:

@rotunda - there is a rave racer at the timewarp arcade in bridgewater, which is in the south west :)

Can someone explain this:

The reason that the boards are hard to repair etc. is that the chips are custom namco ICs right?

Ridge Racer is currently working emulated isn't it?

Does that not mean that we must know what the custom ICs do, and could just remake on in an FPGA?


Sadly not.
Graphics emulation is almost always at a high-level. Someone will have emulated the processor and how it interacts with memory etc, but then it kinda stops at where the processor puts stuff in memory for the graphics system.
People then work out ( clever guessing) what these codes mean and do their best interpretation of how to draw stuff on the screen with their own homemade graphics routines (that’s how some emulators can use direct3D and run at higher resolutions - they’re very ‘high level’ interpretations)
So it might look very similar if done well, but it’s using different methods and a long way from the timing/function perfect stuff you’d need to do it in an FPGA, should you be able to get something 5V compatible and powerful enough to do the job and then find a way to interface it to the original chip location and pinout.

Better off getting emulation as good as possible.
http://www.philwip.com -sibling 'fix-off' (I’m losing by miles).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bobbydilley Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 2:23pm
Ah thank you for explaining that, that does make sense. I'm so impressed that they can guess what to do from just a bunch of data in memory! That does make sense though, I was always confused when looking at emulator projects how they just have the cpu emulator code and none of the other chips seem to be there. Do you know if there are any arcade emulator projects where they emulate all the way down to the raw hardware level?

I suppose if you really wanted, you could get a logic probe on an IC and watch what data goes in and out and try to figure out what the IC was doing with it? But I guess with so many ICs it would take ages and probably isn't worth it for the 1 frame or whatever of difference you get between that and soft emulation.
https://dilley.uk/arcade
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Bods Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 2:30pm
It's not a driving game I've played apart from a couple of goes when it was first out
 
Would like to be playing it on my mame driving cabs, still need to do some work on them yet to get working good.
 
What sort of spec PC do you need to get them running decent and what Emulators best
 
Its a real shame the boards are an issue to keep the original machines running, nothing worse than not being able to use proper hardware in Arcade Cabs.
 
Just reading a little about it, fact another company Evans & Sutherland were also involved in the GFX side isn't going to help
 
 
Is it worth asking them for info too
 
Don't know if you could 100% believe them when they say they don't have anything or info for these boards now, they will say anything to get rid of people at most places. I know most aren't interested in things that don't make them money
 
Is a real shame if they don't show any interest in their past products, If I had a company that you could be proud of what you've achieved over the years I certainly would want to see people still using them, surely they could have some of these chips reproduced and sell them if it made money still
 
 
WANTED! Buggy Boy Junior Rear Seat. Continental Circus Cockpit Lower Rear Light Plexi and more space
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Post Options Post Options   Thanks (0) Thanks(0)   Quote yoganuggy Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 2:33pm
Originally posted by Arcman Arcman wrote:

I am nearly finished making it Mame convertible (i.e I can interchange in five minutes between original board and pc) using all the original parts, no wires cut, and utilising groovymame and an uhid.


Looking forward to reading this Arcman. I've a rave racer cab and am starting to look into making it PC/groovymame compatible but plug-and-play so it can be easily switched back to the RaveRacer PCB
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Arcman Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 4:38pm
Looking forward to reading this Arcman. I've a rave racer cab and am starting to look into making it PC/groovymame compatible but plug-and-play so it can be easily switched back to the RaveRacer PCB
[/QUOTE]

Cheers, getting there slowly, it does require both rear casings to come off, the top to change the hantarex input source, and obviously the bottom casing to remove the original PCB stack and connect up to the Molex connectors (steering, gearbox etc etc) but it's doable in 5-10 mins. 

It's a birds nest of wires in there at the moment, but working, need to get the Topper back on and wired up and calibrate the monitor output a little better then I'll be sure to post back on here. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote John Bennett Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 4:56pm
Originally posted by bobbydilley bobbydilley wrote:

Ah thank you for explaining that, that does make sense. I'm so impressed that they can guess what to do from just a bunch of data in memory! That does make sense though, I was always confused when looking at emulator projects how they just have the cpu emulator code and none of the other chips seem to be there. Do you know if there are any arcade emulator projects where they emulate all the way down to the raw hardware level?

I suppose if you really wanted, you could get a logic probe on an IC and watch what data goes in and out and try to figure out what the IC was doing with it? But I guess with so many ICs it would take ages and probably isn't worth it for the 1 frame or whatever of difference you get between that and soft emulation.


Some of the last major games without custom ICs were Double Dragon and Ghouls and Ghosts and I think someone has used the schematics to clone Ghouls and Ghosts down to the IC level in an FPGA. Great experiment, although I bet most wouldn’t spot the difference in the game.

With these graphics ICs, it’s along the lines of 3D instructions in and video out, so all you ever see is a black box, no matter what you probe. But because 3D (like 2D) tends to have common routines/techniques/algorithms, you can get it damn close with a bit of effort, despite not knowing the circuit. Ridge Racer is also far more basic than things like Sega Hikaru, which isn’t emulated so well.

However, even if you knew the contents of the chips, there’s problems in replicating them:
A run of custom ASICs is in the £millions territory, rather than £1000’s
FPGAs won’t have the same pinout
5V FPGAs are obsolete.
Plus it’s all lots of effort to port stuff.

Ultimately, if emulation can be spot-on, down to the milliseconds for input timing, then that’s the route as you’re fighting a losing battle to ‘frankenboard’ games of such complexity, I believe.

Edited by John Bennett - 11 Jul 2019 at 4:57pm
http://www.philwip.com -sibling 'fix-off' (I’m losing by miles).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lix Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jul 2019 at 5:29pm
I figured out a bit of the 3D rendering on the System 22 boards a while back while trying to diagnose the lack of 3D on one of my boardsets, the textures aren't rendered to a framebuffer but gouraud shaded polygons which represent the texture co-ordinates are, as well as the colour attributes and texture index into every pixel. The framebuffer is then read out on the next frame into the address lines of the texture roms which is where the lookup occurs and then gets fed into the palette ram. There are two identical banks of texture roms which handle odd and even horizontal pixels, I guess due to the speed of rom access. This is why on certain boards with texture faults you can get very fine vertical lines on specific textures, as they're running through Fujitsu mask roms and they do like to die.

What I didn't figure out was how the DSP geometry processing circuitry works, which is where I think the fault specific to these boards with no 3D lies. However the Texas Instruments 320C25 is fairly well documented so creation of an FPGA core for that shouldn't be too hard, and the 680x0 for the main CPU already exists. It is all just fixed point maths and rendering textured polygons. Making a System 22 has been on my todo list for a while, got Sega Model 2 on that list also.

As for the information about repairs and diagnostics being unavailable, it doesn't really surprise me. I've worked at plenty of hardware and software tech companies to know that it's generally seen as a 'Not in our best interests' sort of thing. A lot of companies won't release stuff, even old generation, because it's full of 'commercially sensitive' secrets. Reasons such as "yeah, we stole that idea / system / IP, and don't want to be sued", or "we're a bit embarrassed about that code", plus the legal department would have a fit. So it's easier just to throw it away.

I worked for a games developer once, we worked on converting some arcade games to various consoles and a publisher once sent us a hard drive with the original source code for these machines to us. The developer closed down and I moved on. Couple of jobs down the line and I end up working for the same publisher again, so we put in a request for the source code of the game we're meant to be converting and they tell us that the source code was lost a couple of years back. Oh, so that hard drive that I once had access to was the only copy? Oh well, there you go.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rotunda Quote  Post ReplyReply Direct Link To This Post Posted: 12 Jul 2019 at 1:52am
Lix, your post is extremely interesting! It's great to see people with such great knowledge are actively working on this stuff.

Is there any way i can help with your research? Maybe we should assemble a team of members to really dig into this stuff and see if we can keep the dream alive
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