What is your thoughts on FPGA arcade board replacements?

[redsteakraw]

What is your thoughts on FPGA arcade board replacements? For those who don't know a FPGA is a special chip that can be programed to actually become other chips so it can emulate hardware in hardware which can come close to a perfect re-implementation or replacement if done right. Unlike MAME you can make the chip run at the same speed and act and load the ROM in the same way and have the same exact bugs and you can update the outputs to more modern outputs like Displayport, HDMI or just regular VGA. There are current projects that have re-implemented some games and there are even replacement boards on the market. I know there is a Williams multi FPGA board and a Berzerk FPGA. There also is the MiST FPGA project that is implementing arcade chipsets with some that are Works In Progress. What are your thoughts on this? Is this okay to preserve faulty boards like Berzerk that may not survive much longer. Which boards or games do you think are in need of an FPGA implementation? What are your thoughts on this in general?

[Osgeld]

FPGA is treated like a holy grail among fan's (for some reason) but at the end its all down to execution, good emulation will be good, bad emulation will be bad.

 

In reality we are well past the point of a computer having too much to do that it can't properly emulate anything an FPGA could and its just another choice ... do you pay 225 dollars for 40$ worth of parts with 5 pirate games cause its magical special FPGA, or do you get a 50$ (or less) computer that runs robotron just as well, but have to deal with an OS and a bigger box

Edited March 9, 2019 by Osgeld

[redsteakraw]

FPGA is treated like a holy grail among fan's (for some reason) but at the end its all down to execution, good emulation will be good, bad emulation will be bad.

 

In reality we are well past the point of a computer having too much to do that it can't properly emulate anything an FPGA could and its just another choice ... do you pay 225 dollars for 40$ worth of parts with 5 pirate games cause its magical special FPGA, or do you get a 50$ (or less) computer that runs robotron just as well, but have to deal with an OS and a bigger box

It's not really pirate if you have the broken board and the Cabinet. The williams and Berzerk boards are designed to literally replace the broken board. They also may have a license, I don't know. It isn't anything like throw 1000 MAME roms on a device. They also can run more accurately running at the same clock speed having the same slowdowns and same hardware bugs. They also have zero input lag and don't have to do any software translations. FPGA like it or not may be the best thing going forward. How many parts or fixes can we expect in 100 years? At least FPGA can adjust to newer displays and account for dwindling supplies of chips. The raspberry pi is all well and good for what it is but MAME can't do things the same way real hardware can proof of that is how it loads objects which is how they knocked the DonkeyKong record down. Furthermore input and display lag will also be problems with MAME compared to hardware.

[Osgeld]

Ah didn't know that an fpga device magically fixes display lag

 

lets get one very basic thing down, FPGA is NOT real hardware (yes its hardware but its not THE hardware) it is a large array of logic gates programmed to emulate or simulate real hardware, which can vary drastically depending on who did it

 

it has its pro's and con's, its just another choice

[redsteakraw]

Ah didn't know that an fpga device magically fixes display lag

 

lets get one very basic thing down, FPGA is NOT real hardware (yes its hardware but its not THE hardware) it is a large array of logic gates programmed to emulate or simulate real hardware, which can vary drastically depending on who did it

 

it has its pro's and con's, its just another choice

 

It fixes some sort of lag since you can have a pure digital signal with no need to translate to analog you save on some time and having the same speed clocks you can poll the input the same exact way without having to do USB translations. It won't fix the lag from the input to the displaying on the actual screen but it fixes all of the other hardware lag. Yes you can have a very inaccurate FPGA implementation but you also can have a very accurate one as well. A skilled person could test the input and out put of the device and ensure it meets the same specifications and test for it. I never said it magically gets programmed to be perfect I said it can be close to a perfect implementation if done right which is the case. But if you have an open ecosystem you can share some blocks like the 6502 or other common processors so the important bits can be mature by the time someone wants to work on the dedicated or less common chips needed for a board. I see it as the option going forward shy of actually making systems on a chip for every board which is an even higher threshold. Emulation is an option but is limited far more than a skilled FPGA implementation. When you are talking about drop in replacements for an arcade cabinet, a FPGA just seems like the better solution.

[griz]

I love FPGA. I've got a JROK in my Defender. But I also have the original boardset in there too. I can't tell the difference in gameplay. The Jrok is reliable and I'm happy with it.

 

I have a 60-in-1 (not fpga) in a Super Pacman cabinet. When playing most of the classic games I can't tell the difference either. But there are some games it can't fully handle. For example the sound in Gyruss. Still, there are many older classics it plays just fine like Pacman.

 

Arcadeshop has a number of different fpga boards :

• Berzerk/Frenzy/BZF Multigame JAMMA PCB
• BitKit FPGA Multigame JAMMA PCB
• Williams/wSYSFPGA Multigame JAMMA PCB
• Mylstar/MSF Multigame JAMMA PCB
• Taito/ZooQ Multigame JAMMA PCB

As original hardware fades from the world FPGA and emulation will be there to keep things going.

 

The real extinction seems to be the Arcade CRT Monitors. By the way, anyone have a G07 (or similar) monitor for sale?

 

 

When you are talking about drop in replacements for an arcade cabinet, a FPGA just seems like the better solution.

 

The Jamma standard makes this nice. The Jrok and 60-in-1 are both drop-in replacements for original hardware as are the other boards I listed above. Makes me want to make some new arcade cabinets ... if only I could get some monitors!

Edited March 10, 2019 by griz

[redsteakraw]

I love FPGA. I've got a JROK in my Defender. But I also have the original boardset in there too. I can't tell the difference in gameplay. The Jrok is reliable and I'm happy with it.

 

I have a 60-in-1 (not fpga) in a Super Pacman cabinet. When playing most of the classic games I can't tell the difference either. But there are some games it can't fully handle. For example the sound in Gyruss. Still, there are many older classics it plays just fine like Pacman.

 

Arcadeshop has a number of different fpga boards :

• Berzerk/Frenzy/BZF Multigame JAMMA PCB
• BitKit FPGA Multigame JAMMA PCB
• Williams/wSYSFPGA Multigame JAMMA PCB
• Mylstar/MSF Multigame JAMMA PCB
• Taito/ZooQ Multigame JAMMA PCB

As original hardware fades from the world FPGA and emulation will be there to keep things going.

 

The real extinction seems to be the Arcade CRT Monitors. By the way, anyone have a G07 (or similar) monitor for sale?

 

 

The Jamma standard makes this nice. The Jrok and 60-in-1 are both drop-in replacements for original hardware as are the other boards I listed above. Makes me want to make some new arcade cabinets ... if only I could get some monitors!

 

Monitors are a problem however with a worse case scenario FPGAs can be adapted to output lag free digital output on modern displays and can even have built in scan-line generators. This is of-course the nuclear option but having a digital display is better than no display.

[youxia]

I don't have any FPGA board atm but I am watching MiSTer closely and may get it one of these days just for kicks. But that would be mostly for 8-bit micros and early consoles. Arcade cores are nice, but there's just a handful of them and unless somebody (AI 15 years from now on? you read it here first) figures a wholesale method of programming (tx Osgeld) all the different arcade roms, it's irrelevant for me as an arcade machine. Sure, NeoGeo is coming but that's still leaves a giant chunk of arcade library to be covered.

 

Simply put, MAME is king, and won't be dethroned any time soon. If you're a lag fanatic, you can consider a GroovyMame + a CRT, or even a low-lag LCD. It can be whittled down quite substantially. I spent last year participating in the Arcade HSC compo using mostly RPi, recently PC, and don't seem to be doing too badly, despite some unavoidable lag.

 

Then there are shaders, quality of which got to the point that even a CRT die-hard fan such as myself must admit they are now a valid alternative to the real thing. Not available on FPGAs though.

[griz]

Then there are shaders, quality of which got to the point that even a CRT die-hard fan such as myself must admit they are now a valid alternative to the real thing. Not available on FPGAs though.

 

Link?

[Keatah]

Well I currently prefer and recommend software emulation for a multitude of reasons. You just can't beat the added functionality like configuration menus and rom selectors. Not forgetting the vast storage and file manipulation capabilities of even the most basic PCs.

 

I also like that many things are pioneered first in software. Emulators supporting new file formats is a good example. Some Apple II emulators are now supporting a new archival format called a2r/woz. Last year they weren't.

 

And let's not pass up the fact that software emulators have a larger developer base. Oftentimes there are several people working on one specific driver or emulator. And the ecology of software emulation is simply bigger and will work on literally billions of existing devices.

 

---

 

That's not to say I don't appreciate FPGA and what it can deliver. Small Jamma board-modules or those 60-in-one boards are very simple turnkey solutions to faulty original hardware. And they don't need much hardware or software knowledge to get going.

 

Enthusiasts of "preservation" are still going to focus on keeping the original article, board, piece, item-of-interest in perfect operating condition. But documentation is of growing importance. Schematics, layouts, all that.. All of that is part of the deal too. Both FPGA and Software Emulation are ways to bring those things into the real world with enough fidelity to where they can be interacted with.

 

In terms of future digital archaeologists FPGA code would likely be easier to decipher and re-issue as new hardware. The logic gates and how they are connected are already clearly defined; whereas SE is a ream of code that will need to be executed (preferably on common hardware everyone understands) to really see results.