MiSTer FPGA - Cave 68000 Core Beta Released

[Dexa]

Hey,
could not find any post mentioning it on here yet:
the first beta release of the cave 68000 core has been released for the mister fpga.

the download is paywalled on patreon atm https://www.patreon.com/posts/dodonpachi-beta-40480207

the whole mister system is getting even more interesting now

anyone running neogeo / other arcade cores on their cab already?

[sven666]

Dodonpachi has been running in mame since 1999 or something.. whats the difference?

[Dache]

Dodonpachi has been running in mame since 1999 or something.. whats the difference?

This is should be completely cycle-accurate by effectively replicating the chipset, and supposedly identical to the PCB.

Audio isn't done yet, I'm guessing? Still very cool though.

[Ploppers]

FPGAs aren't any more or less accurare than emulators, its simply how well the machine is implemented in either.

Unless you have the 100% original HDL source and can program that into an FPGA, its really mostly best effort and sometimes best guess how the original operated.

[arcnl]

For me the biggest advantage is that it is (potentially) a lot more hassle free than other stuff. No faffing about with crtemudriver and god knows what else. I get the other advantages of lag and whatnot too but honestly i'm in the "retropie is just fine" and i'm sure i personally won't notice the difference. It's the convenience i'm interested in.
I agree that for most systems this is more like a sortof approximate simulation than an actual emulation. That won't happen apart from the most simple of things that do have full specs.

[Ploppers]

Oh yeah definately, dont wanna come off as being down on it at all. Even thinking about a mister setup for my astro, because of its size, power and ease of use.

[Dache]

Yeah, I say this should be more accurate, not necessarily that it definitely will be. If properly implemented, it should be identical to the PCB, but I don't really know anything about programming FPGAs and no idea how good the guy doing this one is.

[buffi]

If properly implemented, it should be identical to the PCB

Dunno what properly means here, but definitely not the case.
See the docs from Mister github.

https://github.com/MiSTer-devel/Main_Mi ... i/Why-FPGA

Some people insist it's not emulation but rather true hardware replication, while any simulation using a traditional CPU should be referred to as emulation. I have my own opinion here. From my point of view, if the FPGA code is based on the circuitry of real hardware (along with the usual tweaks for FPGA compatibility), then it should be called replication. Anything else is emulation, since it uses different kinds of approximation to meet the same objectives. Currently, it's hard to find a core that can truly be called a replica – most cores are based on more-or-less functional recreations rather than true circuit recreation. The most widely used CPU cores – the Z80 (T80) and MC68000 (TG68K) – are pure functional emulations, not replications

The example there even mentions that MC68000 (which Cave 1gen uses) is an functional emulation, so this will definitely not be 100% pcb accurate.

[pubjoe]

I’ve been following MISTer and have been on the verge of buying for quite a while. Dunno why I haven’t yet. It looks fantastic and has a lot more potential. It’s a pretty great deal with the subsidised DE10 board.

[Dache]

Dunno what properly means here, but definitely not the case.
See the docs from Mister github.

https://github.com/MiSTer-devel/Main_Mi ... i/Why-FPGA

Some people insist it's not emulation but rather true hardware replication, while any simulation using a traditional CPU should be referred to as emulation. I have my own opinion here. From my point of view, if the FPGA code is based on the circuitry of real hardware (along with the usual tweaks for FPGA compatibility), then it should be called replication. Anything else is emulation, since it uses different kinds of approximation to meet the same objectives. Currently, it's hard to find a core that can truly be called a replica – most cores are based on more-or-less functional recreations rather than true circuit recreation. The most widely used CPU cores – the Z80 (T80) and MC68000 (TG68K) – are pure functional emulations, not replications

The example there even mentions that MC68000 (which Cave 1gen uses) is an functional emulation, so this will definitely not be 100% pcb accurate.

Oh, that's a shame, I thought we understood it more than that. It'll at least be interesting to compare it to MAME and the PCB when the authors reckon it's done enough.

[geotrig]

I’ve been following MISTer and have been on the verge of buying for quite a while. Dunno why I haven’t yet. It looks fantastic and has a lot more potential. It’s a pretty great deal with the subsidised DE10 board.

I've seen the odd few bits posted about on Twitter and the likes for a while but have never really looked into the specific s.... So is this better than the picture I'm running and runnable in a cab

[pubjoe]

It’s runnable in a cab with adapters. Short version: Overall It’s not better than groovymame. Nowhere near. Mame is the result of decades of work now.

There’s a few things I really like about it.

• It’s low powered and inherently very optimised.

• From what I’ve read there are some cases where shortcuts have been used but with behaviour that is entirely accurate for purpose. I’m not at all qualified to argue with anyone but while many processors are technically emulated, the result to a user *can* still be better accuracy. I have read that CPS1 on MISTer runs at correct speed, which Mame has never quite managed due to a wait state issue (look up Hyper Fighting bug reports).

• Lag. Near enough a non-issue on groovymame but a very substantial one with alternate low-powered devices that run retro arch. As this is all running at hardware level There’s no OS graphics drivers / framebuffers to worry about - not to mention audio. And on this note, no frame-tethered input drivers. It’s another minor point but using Mame can sometimes fudge up complicated fast inputs.

• Community drive. There are a lot of very talented developers that are working very hard on this. It’s quite an exciting thing to follow progress on / it makes me nostalgic for early Mame news

It’s hard to talk about alternatives without offending Mame. I’ve seen those threads! Mame is probably my favourite produce from the internet. It’s an incredible example beyond my comprehension of what can and is being achieved with an open source project.

MISTer is a very interesting alternative. It’s early days but I feel it’s potential is very exciting and I’m very impressed with what FPGAs have done for old video game hardware so far, like the one in my SD2SNES.

(Sorry. My inner dork popped out)

[Dexa]

It’s runnable in a cab with adapters. Short version: Overall It’s not better than groovymame. Nowhere near. Mame is the result of decades of work now.

i´m thinking about using it in a naomi cab. Inputs should work via a JVS-PAC (= usb keyboard inputs) and video should work via the I/O daughter board which has a VGA output.
Guess i have to order a few parts now

[neokoen]

I guess when this thing gets released there will be many more people getting interested
( from a post on neo-arcadia http://www.neo-arcadia.com/forum/viewto ... 14&t=72568 , I do not have any more info )

[neokoen]

just in case you missed it:

[Dexa]

its out now: https://github.com/MiSTer-devel/Arcade-Cave_MiSTer
havent tested it myself yet.

looks like support for DonPachi and Dangun Feveron is coming in the future.

[poodude]

There are a ton of ways to connect mister to a jamma cab. I have an old J-Pac that works just fine. The J-Pac, I-Pac, and JammASD have native support in mister. Its built into the mister.ini config. There is also the Mister Jamma Adapter by Antonio Villena.

The latest version of this core seems to run perfect now.

[matt5cott]

I guess when this thing gets released there will be many more people getting interested
( from a post on neo-arcadia http://www.neo-arcadia.com/forum/viewto ... 14&t=72568 , I do not have any more info )

Yep, I've got a DE-10 nano on the way specifically to be ready for this.

[pubjoe]

I’m waiting on one of those too. Plenty of ways to connect to a cab like poodude says, but still, the mistercade looks like the loveliest way.

[matt5cott]

MiSTercade was available for pre-order for $170 which has now sold out (shipping claimed "summer") I was going to get involved but the cost of shipping + tax made it undesirable, there are other projects such as Irkens https://irkenlabs.com/85-mister-de10-na ... a-expander to keep an eye on anyway.