Capcom CPS1 C-board fix
- Thread starter lix
- Start date
channelmaniac
Newbie
- Credits
- 38CR
If you have any dead, unrepairable, or corrosion damaged CPS-2 A boards you have a nice source of a CPS-A-01 chip to fix a messed up A board and a CPS-B-21 chip to fix or convert a C board.
Enjoy!
Enjoy!
rockbottom
User
For those that don't know, there's no longer any reason to patch roms or modify the c-board, just keep it all original, replace the battery if necessary, get an Arduino+lcd shield and use my keys. Updated earlier this year, all tested and fully working (b01,b21,b16 are fixed now)
rockbottom2020-11-07 15:14:21
rockbottom2020-11-07 15:14:21
Monstermug
Active member
link to keys aren't working
rockbottom
User
Monstermug said:
fixed
John Bennett
Senior Member
yoganuggy said:
Yes, saw that the other day.
Incredible effort and none of that Patreon stuff - all up there for everyone to make use of
John Bennett
Senior Member
J69 said:
If the custom chip has failed, there's nothing out there
And even if someone does reverse engineer it, you've got two problems:
1. 5V FPGAs are pretty-much obsolete, so it's finding old stock (you don't want to go down the 3.3V to 5V interfacing route with a PCB with stacks of level converters on it). I'd assume there's zero chance of getting something in the same footprint and with a compatible pinout either...
2. Unlike the C-board which is a convenient plug-in device, the custom on the a-board is a surface mount device in the middle, sandwiched between other boards. Feels like a nightmare to get a homebrew PCB-based replacement interfaced into that without a frankenboard rats nest of thin wires. By that point you might as well have made your own A-board if you're that desperate for 'original' hardware over emulation.
I'm hoping in the next few years we'll start to see homebrew silicon designs getting made at fab-for-hire factories, so we can crowdfund getting custom chips that people have reversed and released the HDL for. Better production processes and yields should make it more cost efficient now compared to 80's chip technology. Even if it's still an FPGA die as a chip-on-board / multichip module. It's very hopeful but I still have faith!
With the schematics that Loic has drawn up it's tied up a few things I was unsure about the A custom chip and what certain signals do but we could still do with a proper reverse of that chip. I've managed to repair and get five A-boards running now, one board has a ceramic A custom which should be easy to cleanly decap and photo. I'de be tempted to decap it myself and try to keep it functional but I don't have a microscope to photo it. I nearly bought an Olympus BHM metallurgical microscope from an industrial auction, it went for around £720 in the end (all fees included) which I regret missing out on. I have a precise microstepping X-Y stage all ready to go when I do get one.
Certainly will be good to see a C-board replacement made with an FPGA using these schematics though.
With the schematics that Loic has drawn up it's tied up a few things I was unsure about the A custom chip and what certain signals do but we could still do with a proper reverse of that chip. I've managed to repair and get five A-boards running now, one board has a ceramic A custom which should be easy to cleanly decap and photo. I'de be tempted to decap it myself and try to keep it functional but I don't have a microscope to photo it. I nearly bought an Olympus BHM metallurgical microscope from an industrial auction, it went for around £720 in the end (all fees included) which I regret missing out on. I have a precise microstepping X-Y stage all ready to go when I do get one.
Certainly will be good to see a C-board replacement made with an FPGA using these schematics though.
rockbottom
User
Amazing work by Loïc, in a discussion somewhere else he said he's interested in doing A too but taking a break for a while. Fair enough, something like this is an insane amount of very tedious work... hopefully good things will come to those who wait
As for the physical challenge of making a replacement, flexible pcbs are getting cheaper, Furrtek is close to releasing stuff like PCM and NEO-C1 for NeoGeo on flexi's, gotta be the way forward, if only as an adapter up to a rigid sub-board.
As for the B, kinda crazy seeing every detail clear as day, like config registers etc. If only I had this 18 months ago when I was figuring out the pre-b21 key configs... would have saved many hours of head scratching
rockbottom2020-12-05 17:07:51
As for the physical challenge of making a replacement, flexible pcbs are getting cheaper, Furrtek is close to releasing stuff like PCM and NEO-C1 for NeoGeo on flexi's, gotta be the way forward, if only as an adapter up to a rigid sub-board.
As for the B, kinda crazy seeing every detail clear as day, like config registers etc. If only I had this 18 months ago when I was figuring out the pre-b21 key configs... would have saved many hours of head scratching
rockbottom2020-12-05 17:07:51
rockbottom
User
John Bennett said:
Damn annoying this, Lattice was pretty much the last-man-standing with 5v stuff, then what do they go and do... suddenly decide you can't play unless you pay $600/year subscription license for the previously free development tools (ispLEVER Classic)
We've still got Atmel/Micochip ATF15xx series on the shelf, which are Altera Max 7000 (EPM7xxx) compatible (can even use an old version of Quartus (13.0) for dev, but still need a unique programmer).
Useful, but you aren't gonna fit a cps A or B in one of those
Sadly can't see situation getting anything other than worse, even 3.3v-core/5v-tolerant stuff getting thin on the ground, just gonna have to live with level shifting, multiple regs etc. all that faff. Personally still got a nice stash of old 5v Xilinx stuff for retro projects, nothing that will do A/B but useful for smaller stuff. Did read something about some Russian company possibly releasing some new 5v stuff, I guess that's our only hope if some new player pops up and decides to take on the niche market...
John Bennett
Senior Member
What's the deal with ispLEVER - do existing copies no longer work due to having to log-in or something? (I've never tried it).
Yes, the EPM's are very useful for little customs, I'm working on something now using one and Quartus 13.0.
Interestingly some new automotive microcontrollers have 5V I/O, so I had hoped that might start a resurgence in 5V FPGAs, but that seems a long shot.
Yes, the EPM's are very useful for little customs, I'm working on something now using one and Quartus 13.0.
Interestingly some new automotive microcontrollers have 5V I/O, so I had hoped that might start a resurgence in 5V FPGAs, but that seems a long shot.
rockbottom
User
John Bennett said:
I'm not sure, haven't used it for a while, didn't really think much of it tbh, but word is existing installation will continue to work for now if kept offline. The previous free license did expire, annually I think, you just had to email them and they'd send a new key. Rumors that simply winding back the system clock fools it also. I guess as it was essentially free they didn't do much to protect it, presumably latest download will now have more hardcore mechanisms in place
There's supposedly unofficial open-source tools for Lattice stuff now, at least for fpga, not sure about cpld, I keep meaning to look into it all, might be an option?
rockbottom
User
Only the B21 chip is programmable, older chips (eg. B04) are fixed config.
So answer depends if your English ffight has a (non-original) B21-based C board. If you have or can source any B21-based C board then you just need Arduino Uno with LCD shield to reprogram it.
Depending on the C board type:
another option is use GadgetFreak's "Arcade Rom Patcher" which supports ffight now, so just patch the roms and use any C board you want
rockbottom2021-03-10 19:45:22
So answer depends if your English ffight has a (non-original) B21-based C board. If you have or can source any B21-based C board then you just need Arduino Uno with LCD shield to reprogram it.
Depending on the C board type:
- If it's one that didn't originally have a battery you need to fit one and do small mod.
- If it's one that did originally have a battery, but it's been removed/modded you need to undo the mod and fit a battery.
- If it's one that did originally have a battery, is still original and unmodded, lucky you
just fit new battery as it's most likely nearly flat by now!
another option is use GadgetFreak's "Arcade Rom Patcher" which supports ffight now, so just patch the roms and use any C board you want
rockbottom2021-03-10 19:45:22
rockbottom
User
Ace` said:
You'd have to be quite lucky
the 5 known Jpn versions each use different chip B01-05, only the very first 900112 ver uses B01 so that's the only one that will work directly with a B21.