Support NeoGAF

[nkarafo]

The cores are free. They show up automatically when you run the update script.

Ok, so with a single FPGA board you can emulate as many systems as you want then? Just like you can swap software emulators?

Wasn't aware of that so i stand corrected on that front.

 

[Walter Matthau]

Ok, so with a single FPGA board you can emulate as many systems as you want then? Just like you can swap software emulators?

Wasn't aware of that so i stand corrected on that front.

Yeah, it's pretty similar to Retroarch in that you just choose your console and game. The big difference is the MiSTer menu interface is very minimal with simple text menus to select your console, game, and settings so it's visually much less interesting to navigate the menus.

 

[DrNeroCF]

That's what I thought but when I tested it on many controllers and systems it's the same across the field. I've even had other people test it.

Leaving on ‘analog to digital’ on systems with analog input in RetroArch will cause that, apologies if that’s an obvious one you’ve already ruled out.

 

[TheGecko]

Leaving on ‘analog to digital’ on systems with analog input in RetroArch will cause that, apologies if that’s an obvious one you’ve already ruled out.

Yeh checked, I never use analogue for racing on the PS1.

 

[nkarafo]

Yeah, it's pretty similar to Retroarch in that you just choose your console and game.

So how does the FPGA chip work exactly?

I thought the emulated system gets "burned" into the chip and that chip becomes that console forever.

I guess i was wrong so what it does is changing it's programming every-time you pick a different system as long as that system "fits" in the chip?

So all you need is a single FPGA system after all? No extra modules or anything?

 

[Walter Matthau]

So how does the FPGA chip work exactly?

I thought the emulated system gets "burned" into the chip and that chip becomes that console forever.

I guess i was wrong so what it does is changing it's programming every-time you pick a different system as long as that system "fits" in the chip?

So all you need is a single FPGA system after all? No extra modules or anything?

When a new core is run the FPGA reconfigures itself. I don't know much about how HDL works, but you're not permanently altering the board in any way.

There are many cores that require a 128 MB SDRAM add on which can cost $60 - $65 depending on who you buy it from.

The DE10-nano used to be $105 a couple years back, but the price has really gone up since then. As much as I like it, there are cheaper ways to play old games and those options work perfectly fine for most people.

 

[SScorpio]

Ok but aren't these cores separate purchases? How much

So how does the FPGA chip work exactly?

I thought the emulated system gets "burned" into the chip and that chip becomes that console forever.

I guess i was wrong so what it does is changing it's programming every-time you pick a different system as long as that system "fits" in the chip?

So all you need is a single FPGA system after all? No extra modules or anything?

The FPGA the MiSTer runs on uses SRAM and the manufacturer stats basically unlimited rewrite cycles.

Outside of the DE10-Nano you need a OTG micro USB hub, cheap ones run $5 to hook up controllers or a keyboard, SDCard for storage, the DE10 comes with an 8GB, and many cores need the SDRAM module. That will give you access to all cores.

The SDRAM is needed because consoles load the game ROMs into it and use it like a cartridge. The onboard DDR RAM doesn't have the access times to be reliable enough. But some cores let you use it instead and you can see glitches in some games.

FPGAs themselves are a chip that have a bunch of logic cells that have a lookup table which for any series of inputs, gives an output. These can then connect to other cells. The programming is defining the lookup tables and connecting the cells together.

With a program like an emulator a check for two inputs would be, if input1=a and input2=b then the result is c. The code first checks input1 and the input2 before giving the result. With a lookup table the checks and output happen in a single cycle. While is why FPGAs can be under 100Mhz while needing a 1Ghz+ CPU to do cycle accurate.

An FPGA like original hardware also does everything at once, so while a console had multiple chips, all of the lookup tables are updating every cycle at the same time. A software emulator is processing thousands of statements to render a single hardware cycle of whatever it's emulating.

That's why FPGAs have the image of being more accurate. The multiple statement processing of a emulator can introduce bugs based on a chip reading before memory is cleared or the like. Reading from a spec sheet the software emulator is written correctly, but the actual hardware is performing off spec or undocumented.

The issues can be fixed in the software emulators, and MAME had multiple things like the above fixed due to Jotego funding those types of issues after creating his FPGA cores.

 

[cartman414]

So this is a thing that will exist soon. Couldn't find any dedicated X68000 threads, but check this out, the X68000 Mini.



It's from the guys who did the Genesis Mini, and the Sega and Taito arcade cab minis, so it's already got a good pedigree. Hopefully the games will be good.