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kevtris

FPGA Based Videogame System

Interest in an FPGA Videogame System  

656 members have voted

  1. 1. I would pay....

  2. 2. I Would Like Support for...

  3. 3. Games Should Run From...

    • SD Card / USB Memory Sticks
    • Original Cartridges
    • Hopes and Dreams
  4. 4. The Video Inteface Should be...



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MiSTer vs Super NT

 

Of course the problem is that they do not have full time people working on cores, etc.. especially no one like Kevtris.
I guess the more powerful FPGA does not matter if you can do everything you need to 99% accuracy with the FPGA you have.

 

Sorgelig, the main MiSTer developer seems to be dedicated full time to the MiSTer. Or at least his productivity is as high as you would expect from somebody dedicated full time.

 

A more powerful FPGA might or might be not relevant for accuracy. It depends on the particular core. Some arcade and dedicated systems require a lot of RAM bandwidth because the original hardware used multiple RAM chips accessed independently on parallel through multiple buses. Or, for later ones, they had chips with a considerable amount of internal RAM. Many times you can't "emulate" this behavior accurately with a single external RAM as most FPGA system have. You have to either do that with internal FPGA RAM (usually called block RAM), which might require a bigger FPGA. Or you have to drop exact cycle accuracy.

 

This is just an example, there might be other reasons why the FPGA size might be relevant. But yes, some particular core might fit perfectly well on a smaller FPGA size, and a bigger or more powerful one won't add anything.

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If shipping is really $50 for a $10 adapter that would otherwise fit inside a $3 USPS bubble mailer, we might consider doing a community group buy. Someone could take names for AA members and which adapters they would like to purchase (I would personally buy one Game Gear adapter, since carts are plentiful and cheap), and when the amount of requested adapters reaches some threshold, the $50 shipping charge becomes negligible.

If the shipping is even remotely close to that of the console itself, I promise I won't be buying.

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I have a Super Nt and Nt Mini and Im still wondering about if I can change cart on the fly.

 

Lets say I play from a rom file from my Nt Mini and wanna go physical cart, can I just pop one in and "run cart" ?

Now I always power down the systems before inserting the cart. Is it needed?

 

Dont wanna screw around with a 2G system :-o

I asked Kevtris this same question and he suggested powering it down.

http://atariage.com/forums/topic/242970-fpga-based-videogame-system/?p=3957275

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According to the PCB picture on this thread http://www.atari-forum.com/viewtopic.php?t=33187,

The FPGA on the Super NT is the 5CEBA4F23C8N with 49K LEs: https://www.mouser.hk/ProductDetail/Intel-Altera/5CEBA4F23C8N?qs=w%252bhYR4jzwbYUpN8%252bflZzzw==

 

MiSTer / DE10 Mini has the 5CSEBA6U23I7 with 110K LEs: https://www.mouser.hk/ProductDetail/Intel-Altera/5CSEBA6U23I7N?qs=hFKXOjF5Mkbg493w%252bJXetA==

 

The second chip has both more "room" (meaning more complex cores can be built inside it) and more internal RAM (meaning more can be done without the external, slower, DDR RAM).

Now bear in mind the FPGA in the NT is bigger than the MiST, so a lot of cores could fit inside of it in theory if somebody were to make the work.

 

I notice the NT FPGA also has more I/O pins, which doesn't affect performance but makes it possible to attach additional hardware (e.g. external RAM, cartridges, etc) to it.

So I suppose the Super NT FPGA is a good choice for a commercial product destined to read carts and potentially other accessories.

 

For comparison, the FPGA in the Retro AVS is much smaller, a Spartan 6 XC6SLX9 with 9K LEs (5x less than the NT). It's enough to run a NES core without additional cartridge hardware.

Extra logic such as reading ROMs from an SD card would probably not fit inside it, with such a low capacity.

Edited by Newsdee

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According to the PCB picture on this thread http://www.atari-forum.com/viewtopic.php?t=33187,

The FPGA on the Super NT is the 5CEBA4F23C8N with 49K LEs:

MiSTer / DE10 Mini has the 5CSEBA6U23I7 with 110K LEs:

That means that the FPGA on the NT is also a slower speed grade (C8N) than the one on the MiSTer (-7). Again, this is irrelevant for any core that can meet timing on the slower speed grade already. Probably only significant f you would like to port 16-bits systems.

 

The second chip has both more "room" (meaning more complex cores can be built inside it) and more internal RAM (meaning more can be done without the external, slower, DDR RAM).

DDR RAM is actually faster that internal RAM, and even SDRAM is not that much slower. But external RAM, unless you use static RAM, has a much higher latency. And again, internal RAM is divided in blocks that can be used all in parallel if needed.

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25% off eBay coupon up to $25, good if you need an sd2snes, PAYWCARD

I'd be wary of buying a flashcart on eBay. Could very well be a clone and even the seller isn't aware. I'd stick with waiting for krikzz black Friday sale.

 

Sent from my SAMSUNG-SM-J727AZ using Tapatalk

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I'd be wary of buying a flashcart on eBay. Could very well be a clone and even the seller isn't aware. I'd stick with waiting for krikzz black Friday sale.

 

Sent from my SAMSUNG-SM-J727AZ using Tapatalk

 

I got mine on eBay with no issue and it's legit, I bought from retro_saikou

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I got mine on eBay with no issue and it's legit, I bought from retro_saikou

Be wary. I purchased a defective Everdrive N8, thankfully got a refund.

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Be wary. I purchased a defective Everdrive N8, thankfully got a refund.

 

Yeah I mean, be safe, but my cart is 100% legit so I was happy with it

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I have a Super Nt and Nt Mini and Im still wondering about if I can change cart on the fly.

 

Lets say I play from a rom file from my Nt Mini and wanna go physical cart, can I just pop one in and "run cart" ?

Now I always power down the systems before inserting the cart. Is it needed?

 

Dont wanna screw around with a 2G system :-o

Hot plugging the carts is unlikely to cause permanent damage to system or cart hardware, however I would strongly advise against it. It is also a great way to delete / corrupt battery backed save data. :skull:

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25% off eBay coupon up to $25, good if you need an sd2snes, PAYWCARD

Just tried to use code and it says no longer accepted. :(

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It's basic common sense. You don't unplug or plug in when power is on. Why would you even want to?

Ever tried to "fry" NES /Famicom, or Atari carts? It works surprisingly well on nrom Famicom games, since the ppu is on one side and the cpu on the other. I was playing my one-of-a-kind Famicom "Mario Surer Bros"

http://nintendoage.com/forum/messageview.cfm?StartRow=1&catid=10&threadid=166162

https://sta.sh/02bjlf22fdqg

on my AVS, with the game running, and managed to life one edge of the cart out such that the graphics fubared, then pressed it back down and kept on playing. Pretty sure if frying or yanking carts could kill them, very few nes and ataris would have survived, especially the "blinky screen" nes toasters... :skull:

 

People need to lighten up. Old 5v chips tuff stuff and aren't gonna blow if you randomly disconnect a few pins... :P

 

You'll just lose your save data if it happens to confain battery backed ram. :dunce:

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That means that the FPGA on the NT is also a slower speed grade (C8N) than the one on the MiSTer (-7). Again, this is irrelevant for any core that can meet timing on the slower speed grade already. Probably only significant f you would like to port 16-bits systems.

 

 

DDR RAM is actually faster that internal RAM, and even SDRAM is not that much slower. But external RAM, unless you use static RAM, has a much higher latency. And again, internal RAM is divided in blocks that can be used all in parallel if needed.

Would it be fair to say that the FPGA in MISTer gives more options to developers and makes cores a little easier to develop for it?

 

If I understand what you are saying (and restating for the benefit of all) the speed matters to more accurately replicate original timings on later systems, and the RAM is part of that. Having more internal RAM means less complicated coding to deal with the latency in accessing DDR (for example).

 

I get the sense that for somebody wanting to learn FPGAs, the DE10 is a better choice anyway (versus a hypothetical hacked Super NT).

 

I may be simplifying things, but trying to differentiate with e.g. comparing two CPUs.

Edited by Newsdee

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Would it be fair to say that the FPGA in MISTer gives more options to developers and makes cores a little easier to develop for it?

Certainly. A bigger FPGA is very useful for developing. When you develop the core, many times you need extra space for debug logic. The main debug tool for FPGA development is some kind of internal logic analyzer. The more memory it has (and can only use internal RAM) the better!

 

As a matter of fact I started developing my ST core on the DE-10 Standard Terasic board. Which is the big brother of the DE-10 Nano used by the MiSTer. But this is a more expensive board.

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Hot plugging the carts is unlikely to cause permanent damage to system or cart hardware, however I would strongly advise against it. It is also a great way to delete / corrupt battery backed save data. :skull:

 

Hot-plugging only kills flashrom and magnetic media. Anything else requires static electricity to be involved. Even then, it data has to be written to it while being hotplugged to have any deleterious effect.

 

The reason for the overkill warnings on modern consoles is because people have been hotplugging the savegame carts since the N64/PS1 and ejecting them while the game was autosaving = game session toast. Hotplug a USB stick or a SD card while it's being written to, and you may lose the entire contents of the flashrom since the file table tends to eat it.

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Hey all - long time, I need to catch up on this thread ;-)

 

Had a question about Nt Mini - playing Vs. Duck Hunt , the patched arcade rom that allows you to play it on NES systems (Similar to what was being sold here: https://www.retrousb.com/product_info.php?cPath=29&products_id=96)

 

I'm just trying rom images at this point, both on Everdrive and the NT Mini SD card -

 

I can't get the gun to register at all and get stuck at "shoot to select 1 or 2 player" -

 

Has anyone or could anyone try running this? My NT Mini plays regular duck hunt and other gun games fine. I'm trying to rule out if its a NT Mini issue.

 

Any info appreciated - thanks!!

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Hey all - long time, I need to catch up on this thread ;-)

 

Had a question about Nt Mini - playing Vs. Duck Hunt , the patched arcade rom that allows you to play it on NES systems (Similar to what was being sold here: https://www.retrousb.com/product_info.php?cPath=29&products_id=96)

 

I'm just trying rom images at this point, both on Everdrive and the NT Mini SD card -

 

I can't get the gun to register at all and get stuck at "shoot to select 1 or 2 player" -

 

Has anyone or could anyone try running this? My NT Mini plays regular duck hunt and other gun games fine. I'm trying to rule out if its a NT Mini issue.

 

Any info appreciated - thanks!!

Light guns are not compatible with modern flat panel / HDMI displays. You must use a CRT with standard definition (composite, rf, etc...) analog input.

 

I think the hacked ROM variant is stuck on easy mode. I have the old repro with the dip switches. On normal or extreme difficulty setting, you actually get 3 ducks / skeet per screen instead of 2 on rounds 5, 6, 11, 12.

 

So much fun to "shoot the dog" in the bonus rounds. Sometimes I do it on purpose... :evil:

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I'm assuming he's using analog out to a CRT or something.. He already said it works fine on regular duck hunt and other light gun games. :P

 

I'd say.. you have an Everdrive already, so plug it into a regular NES and check there. I'd try it myself but I'm too lazy. :lol:

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