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MiSTer FPGA - 7800 Core

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1 hour ago, youxia said:

 

So, you guys have some links to proper, comprehensive tests to validate these statements? I'm genuinely interested.

 

 

I was waiting for that.  I won't be disarmed by that.  People share experiences, make recommendations, make choices all the time in all areas of life that aren't based on spreadsheet data.  I dont need numbers.  It feels great, responds instantly, I play through entire games this way.  Retroarch with runahead feels no different than the Mister.

 

These are all just toys.  I don't need scientific journal articles to prove that I'm allowed to treat the experiences as equals.

 

This is why the FPGA cult drives me nuts.

Edited by zetastrike
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9 hours ago, Keatah said:

There are those of the FPGA crowd who simply misunderstand. 110KLE doesn't come close to allowing any kind of "per transistor" duplication - which they so much like to believe is what's happening and the source of perceived superior accuracy & performance.

 

It's still higher-level interpretation. Simulation. Let alone all the different delays between nodes and temperature and speed sensitivities - which are characteristics of original hardware lost in translation. It's all still an approximation.

 

SE gets a bad rap from running (and stuttering) on low-power hardware - or running in environments that constantly interrupt the processor with frivolous tasks, like downloading updates and background defragging. Even dealing with stacks of bloated APIs is a hindrance. With SE you really want premium hardware. But it doesn't have to be expensive either. Just below GaMeRZ level is going to be more than sufficient.

 

 

Sort of. My TIA audio is basically gate level identical. Some parts can be basically 1:1. However FPGA's do run differently than ASICs, as silicon and FPGA fabric have different properties. You'd never implement some ram on a transistor basis, nor would you want to. Bi directional busses are best to split on FPGA's, and usually clock enables are a good idea to add, rather than allowing things to be clocked directly by arbitrary signals. Some things make no sense to implement at a gate level. Like an adder would be a fairly large circuit that just increments a number, so in HDL you would do something like x <= x + 1; in a clocked block and have the compiler implement the circuit for you. There's no logical difference. I wouldn't even classify it as an abstraction really. It's more like tokenization of boilerplate circuits. 

 

Almost none of mister's cores are very heavily abstracted though. The vast majority of them are cycle accurate, and run in real time. Many of them, particularly the consoles, are modeled after decaps or schematics of chips. Unlike software emulators, they can have down to gate level accuracy without using a large powerful pc. There's no penalty for that level of detail since everything runs in parallel like the original hardware did. Properly done low level designs are often more space efficient than large abstractions end up being.

 

In a nutshell, yes, both FPGA's software can be accurate, but because FPGA's work extremely similarly to real hardware, it's *much much* easier to write an accurate emulator. In general, people who develop for FPGA (at least MiSTer) value accuracy extremely highly, and make it a priority. Lastly, an FPGA can run at full accuracy with much less hardware. A software emulator would need an expensive PC to run at a comparable level.

 

Some aggressive advertising from some companies has led to a lot of FPGA myths circulating, so I'll try dispel some in a couple of bullet lists:

 

What you will get from MiSTer:
- Low Latency Video. It's bare metal so the FPGA drives the HDMI chip (and analog video) directly. In low latency mode it has roughly 10 scanlines of delay for outputting the picture.
- Low Latency Input. An arm core running linux is responsible for the input. It's been measured with an arduino that some controllers can go from button to core in about a half a millisecond.

- Low Latency Audio. Most software emulators have to buffer audio for around 35+ milliseconds (about two frames). It's output directly on MiSTer.

- Cohesive interface. The UI is simple to save resources and work at original analog resolutions, but the options are consistent and cohesive from core to core.

- No power compromises. MiSTer is capable of running emulators at the same level of performance and accuracy as a very high end PC. 

- Some hardware integration. Things like light guns and original peripherals can work directly with MiSTer.

- Easy setup. Most people are intimidated by the appearance of the electronic components, but in reality they just snap together like legos. You flash the mister firmware to an sd card, pop it in, and you're ready to go. It requires less configuration than retropie.

 

What you won't get from MISTer:

- Instant, perfect accuracy. While most of mister's console cores are at or above the accuracy level of their most highly regarded software counterparts, it's not implicit that they will be written that way. It's easier to make a core accurate in HDL than Software though.

- Fancy flashy UI's that scrape your ROMs and show you little pictures of everything. MiSTer has no GPU, so the FPGA has to use resources to process such things, which is not worth taking away from the cores themselves.

- Some features. The most common one people miss is save states. While a few cores now have save states, most don't, because they are difficult to add in fpga designs. Also missing are things that don't work like original hardware could, like high resolution modes, 80mhz booster chips, etc.

- Cart slots. There's not enough GPIO on the board for them, and part of the goal of the project is to remove the need for discontinued hardware.

 

If you're happy with software, use software. Some people don't care if their pi has a frame skip once in a while or whatever, and that's fine. It's great that these old games can be so accessible. I would say MiSTer will appeal most to people who want something very close to a real-hardware experience with a bit more quality of life and stability than real hardware can provide reasonably. It's certainly an enthusiast-level device, but it DOES have differences and advantages. It's quite subjective whether they will be worth it to any given person or not though.

 

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28 minutes ago, zetastrike said:

I dont need numbers.  It feels great, responds instantly, I play through entire games this way.  Retroarch with runahead feels no different than the Mister.

 

These are all just toys.  I don't need scientific journal articles to prove that I'm allowed to treat the experiences as equals.

 

This is why the FPGA cult drives me nuts.

 

These numbers are pretty easy to measure. "It feels good to me" is a meme at this point :)

 

Unfortunately there's no way good way to describe the proper *feeling* of low latency to people, it's something you have to experience to understand why people like it. It's kind of like trying to describe how good the contrast ratio on an OLED looks to someone who hasn't seen it.

 

Using some hacky tricks like runahead you can get the video latency somewhat close to a bare metal system, but the audio and input will still be a bit behind. Again, this isn't a thing that matters to everyone. If you're happy with such things, then keep using those. MiSTer is better than than them on this particular issue though, and we DO have the numbers.

 

I'd like to point out that FPGA people aren't a "cult". Many of us, including myself, use both software and hardware emulators. I think what you are seeing is probably pushback from FPGA people against overly aggressive software people who come into threads about an FPGA core in order to pee in the cheerios. Not naming any names.

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26 minutes ago, zetastrike said:

I dont need numbers.  It feels great, responds instantly, I play through entire games this way.  Retroarch with runahead feels no different than the Mister.

 

These are all just toys.  I don't need scientific journal articles to prove that I'm allowed to treat the experiences as equals.

 

This is why the FPGA cult drives me nuts.

You are making quantifable claims ("A real PC or a high end phone can achieve just as low lag as an FPGA setup") so yes, you do need to back them up, and not with "feelings", but something concrete. It's an absolutely normal procedure in any hardware-related discussion. Otherwise, it's just noise, most likely projected because you have a bone to grind with the "FPGA cult". But spreading misinformation is no different to these zealots saying how they hate emulation because the lag is "extremely high".

 

And this issue has nothing to do with what works or doesn't for you or anybody else, it's an entirely different matter. Myself, I use all these solutions (real HW, FPGA, emulation) interchageably, since they all have their pluses and minuses. But I do like to base my choices on facts, not emotions and internet say-so. Actually, I also think the lag issue is exaggerated, but that's not an excuse to make unproven or downright false claims about hardware facts.

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I'm not a member of the cult... I'm just there for the food. ;)

For me, the plusses compared to other solutions are boot time, software stability, single UI (can go from one system to another with the controller), loads of 8 bit goodness (pretty much all I need), one controller to rule them all.

What's lacking for me... screenshots and manuals, a few arcade favorites, and some controller options. It's also a jump in price compared to some solutions.

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I have a Raspberry Pi mini desktop arcade thing which I like a great deal. It's awesome for PS1 shooters (upscaling the 3D bits) and I just really like it as a platform for Lynx games. I've had a MiSTer for some time as it's my favoured solution for running old systems on a newer panel TV. I also have original hardware through CRTs. No cult here. I appreciate all methods of playing old games.

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21 minutes ago, 5-11under said:

I'm not a member of the cult... I'm just there for the food. ;)

For me, the plusses compared to other solutions are boot time, software stability, single UI (can go from one system to another with the controller), loads of 8 bit goodness (pretty much all I need), one controller to rule them all.

What's lacking for me... screenshots and manuals, a few arcade favorites, and some controller options. It's also a jump in price compared to some solutions.

 

MiSTer actually has a screenshot feature, although it's at the original pre-scaled, and pre-aspect corrected resolution. Good enough for passwords though :)

 

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I primarily use software or the actual e-waste, but peeing in the cheerios is a terrible idea as...

1 hour ago, Kitrinx said:

In a nutshell, yes, both FPGA's software can be accurate, but because FPGA's work extremely similarly to real hardware, it's *much much* easier to write an accurate emulator. In general, people who develop for FPGA (at least MiSTer) value accuracy extremely highly, and make it a priority. Lastly, an FPGA can run at full accuracy with much less hardware. A software emulator would need an expensive PC to run at a comparable level.

...this is kinda the "big deal" of all FPGA / HDL implementations. Replicating many of the real nasty timing quirks (things like clock skews or other nuances in bus arbiters - especially when they don't work correctly) is way way way easier in an FPGA. The MiSTer developer community has gotten a lot of high accuracy cores extremely fast - so it's not just good for an authentic, low latency experience but also for preservation.

 

It's definitely worth a try if these things are important to you, and you don't already own the pile of junk necessary to play on the original hardware.

 

 

30 minutes ago, Kitrinx said:

MiSTer actually has a screenshot feature, although it's at the original pre-scaled, and pre-aspect corrected resolution. Good enough for passwords though :)

A smartphone can also takes screenshots, just like the ones you'd mail in to Nintendo Power (GATE LEVEL ACCURACY). It can also be used to read manuals. The biggest perk is that many people already own them (check your pockets if unsure).

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What I meant when I mentioned screenshots was showing a picture of the gameplay while scrolling through the list of games... a good memory jogger if you can't remember the name of a game, or if you want to select a game based on the picture... maybe it looks like a shooting game or puzzle game, for instance.

 

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5 minutes ago, 5-11under said:

What I meant when I mentioned screenshots was showing a picture of the gameplay while scrolling through the list of games... a good memory jogger if you can't remember the name of a game, or if you want to select a game based on the picture... maybe it looks like a shooting game or puzzle game, for instance.

 

 

Oh, yeah, those don't work well at 240p (when people are using crt's) and take a lot of resources. It's better to look at mister's interface as a fancy flash cart rather than a simple emulator. It's somewhere in between.

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9 minutes ago, John Stamos Mullet said:

Just curious - but what is the boot time for a Mister from power on to full UI access?

Maybe about 5 seconds.

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1 hour ago, Kitrinx said:

 

Oh, yeah, those don't work well at 240p (when people are using crt's) and take a lot of resources. It's better to look at mister's interface as a fancy flash cart rather than a simple emulator. It's somewhere in between.

and this is going to sound cheesy - but this is one area where I get sincerely disinterested in MiSTer. I already have flash/SD carts for the systems I need them for, and using original hardware is obviously going to have the lowest lag possible. Where RPi has won me over is the really nice looking appeal of Retropie/Emulationstation GUIs. It's completely not "important" but the aesthetics of having a good looking GUI makes the experience more "fun".

 

I think personally, I've long since gotten past worrying about perfect accuracy for this kind of stuff, and really just want a nicely developed product, rather than strict hardware adherence, at the cost of clunky interface.

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Just now, John Stamos Mullet said:

and this is going to sound cheesy - but this is one area where I get sincerely disinterested in MiSTer. I already have flash/SD carts for the systems I need them for, and using original hardware is obviously going to have the lowest lag possible. Where RPi has won me over is the really nice looking appeal of Retropie/Emulationstation GUIs. It's completely not "important" but the aesthetics of having a good looking GUI makes the experience more "fun".

 

I think personally, I've long since gotten past worrying about perfect accuracy for this kind of stuff, and really just want a nicely developed product, rather than strict hardware adherence, at the cost of clunky interface.

Then wtf are you reading this thread for?

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14 minutes ago, Kitrinx said:

Then wtf are you reading this thread for?

Because all of these options for playing these games intrigue me, and it's nice to learn about this stuff, and ask questions before plunking down a large chunk of cash on one if I'm going to be disappointed with the result.

 

Edited by John Stamos Mullet

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Ah, the meme guy is back. I don't have as much practice but let's have a try

 

sshot-2021-04-29-16-38-15.png

 

That schtick where you pretend to be looking for information, but in reality just come here to stir $hit up is rather pathetic. I gave you benefit of a doubt at first, but that won't happen again. The hypocrisy of bitching about nasty "cultists" while at the same time cynically trolling using spoiled child-level "arguments" is quite amusing to watch though. Now, run and see what you can rustle up from your meme folder 🤭

 

And just for the benefit of folks who might think that some of the BS you were spouting is actually true:

 

-no, you don't need to spend 350 USD or more on MiSTer. For ~270 you can experience 97% of the content (minus some of NeoGeo and some CPS)

-yes, there totally is a "well written repository" and it's quite easy to find too: https://github.com/MiSTer-devel/Main_MiSTer/wiki

and also the cultists' den: https://misterfpga.org/

-MiSTer is not a multi-million selling product from a big corporation, so no, you won't always find the parts ready and waiting on Amazon (especially when Covid is on). But a simple search will reveal that there are multiple very solid sellers around the world, usualy well stocked and very helpful when replying to email queries.

-no, RPi is not on the same level when it comes to latency. If that is important to you or not is entirely different kettle of fish.

 

 

 

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37 minutes ago, youxia said:

Ah, the meme guy is back. I don't have as much practice but let's have a try

 

sshot-2021-04-29-16-38-15.png

 

That schtick where you pretend to be looking for information, but in reality just come here to stir $hit up is rather pathetic. I gave you benefit of a doubt at first, but that won't happen again. The hypocrisy of bitching about nasty "cultists" while at the same time cynically trolling using spoiled child-level "arguments" is quite amusing to watch though. Now, run and see what you can rustle up from your meme folder 🤭

 

And just for the benefit of folks who might think that some of the BS you were spouting is actually true:

 

-no, you don't need to spend 350 USD or more on MiSTer. For ~270 you can experience 97% of the content (minus some of NeoGeo and some CPS)

-yes, there totally is a "well written repository" and it's quite easy to find too: https://github.com/MiSTer-devel/Main_MiSTer/wiki

and also the cultists' den: https://misterfpga.org/

-MiSTer is not a multi-million selling product from a big corporation, so no, you won't always find the parts ready and waiting on Amazon (especially when Covid is on). But a simple search will reveal that there are multiple very solid sellers around the world, usualy well stocked and very helpful when replying to email queries.

-no, RPi is not on the same level when it comes to latency. If that is important to you or not is entirely different kettle of fish.

 

 

 

I can't speak for anyone else, but I am NOT here to "stir shit up". But yes - I do have some direct questions about the validity of the accuracy claims, and concerns about the cost and availability of the products being discussed here. These are all valid points whether you want to agree or not. I'm sorry if that bothers you.

 

I like the idea of the MiSTer, sincerely. I wish it had better results with some of the specific games/platforms I'm interested in. Though the accuracy with the 7800 core has my interest up even more. 

 

I also wish it wasn't so price prohibitive compared to pretty much every other option out there - but I understand that it is a niche product and as such - production costs are what they are. $270 is still a pretty large chunk of cash for a product that provides something that can be had for far cheaper with completely acceptable similarity in results for about $50.

 

You can always ignore me if you don't agree with me.

Edited by John Stamos Mullet

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$270 is a good chunk of cash that's for sure, but let's take a 7800 + video mod + flash cart + SD card+ pokey chip 

That's going to be more in the $400 area, even more if you live in pal land like I do.

Now I've tried emulation on the pi 3b+ and on an i7 laptop and I'm afraid I just don't get on with it at all. Believe me I want to but it just feels off to me. I prefer emulators on my original Xbox, that feels closer to the real thing.

I'd love to try a mister, but I need to sell some stuff first, and that's hard to do because I love my original kit. Although the 7800 looks crap on my plasma TV in the family room and that's where I'd like to use it.

 

 

 

 

Edited by mimo
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24 minutes ago, mimo said:

$270 is a good chunk of cash that's for sure, but let's take a 7800 + video mod + flash cart + SD card+ pokey chip 

That's going to be more in the $400 area, even more if you live in pal land like I do.

Now I've tried emulation on the pi 3b+ and on an i7 laptop and I'm afraid I just don't get on with it at all. Believe me I want to but it just feels off to me. I prefer emulators on my original Xbox, that feels closer to the real thing.

I'd love to try a mister, but I need to sell some stuff first, and that's hard to do because I love my original kit. Although the 7800 looks crap on my plasma TV in the family room and that's where I'd like to use it.

 

 

 

 

 

It did go up recently, from $135 to 170 unfortunately, presumably because of the worldwide parts shortage. The minimum you need to get started is the DE10 for $170, at least 32mb of sdram for $30-60, and a cheap otg usb hub for about $9. This is assuming you already have a usb stick or sd card that you can use for roms. The other boards and case are optional.

 

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48 minutes ago, mimo said:

$270 is a good chunk of cash that's for sure, but let's take a 7800 + video mod + flash cart + SD card+ pokey chip 

That's going to be more in the $400 area, even more if you live in pal land like I do.

 

This is getting off topic for sure but, LOL - no.

 

You can get a working 7800 on ePay for $40-$50. The UAV is $25. The Concerto is $99. SD cards are $10. I know Pokeys are scarce, but not $215 scarce.

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It's interesting that the arcade board crowd hasn't figured out that the cheapest way to get a pokey to to tear it out of a Ballblazer cart. 

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48 minutes ago, John Stamos Mullet said:

This is getting off topic for sure but, LOL - no.

 

You can get a working 7800 on ePay for $40-$50. The UAV is $25. The Concerto is $99. SD cards are $10. I know Pokeys are scarce, but not $215 scarce.

Lucky you 

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Years ago I would definitively have chased down the original hardware. But with the 3 options we have today, not so fast. A big issue is connectivity and continued longevity. And of course all the other reasons like reliability, convenience, and space savings.

 

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2 hours ago, mimo said:

[...] let's take a 7800 + video mod + flash cart + SD card+ pokey chip [...]

+ YM2151 + High Score Cart + Covox + xegs keyboard

 

Plus the ability to play the Rescue on Fractalus demo without every other line messed up.

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