FPGA Based Videogame System

[bikerspade]

Also, regarding the LED settings. Is there anyway to just have it off?

You can set the LED brightness to 0

[Andromeda Stardust]

Would it be possible to add a way to take in-game screen shots and have it save them to the SDCard?

I'd love an easy way to do this. It would be useful for a few things to me personally, as well as showing off how incredible the Super Nt really looks..

 

I've taken a few pictures with an iPhone, trying to show scanlines,

 

 

 

but an internally generated screen would be much cleaner.

 

It may also prove useful to show off any inherent bugs, if there are any left.

 

Also, regarding the LED settings. Is there anyway to just have it off? I have a clear SNT, and I usually play it at night in a dark room. The LED can sometimes be a bit distracting. Right now I just have it set to a solid red light, but off would ne a nice option as well.

Nice selection of games my friend. Big fan of Parodius...

 

Good idea but without a CPU it may be difficult to write a PNG encoder for the FPGA. Or one could use raw bitmap, but it would require making a 1080p frame buffer of the entire output screen. I don't think there's enough memory as the output resolution (including scanlines and scalars) is generated procedurally in real time. The only thing that's buffered is a few scanlines worth of native pixels. It's not an emulator so emulator specific functions that are easy with a CPU with unlimited resources, might be difficult or impossible to pull off on an FPGA.

 

And yeah what he said, just set the output brightness to zero. How will you know if it's on though???

 

EDIT: 400 pages yay!

[cybercylon]

 

It worked for me, tried StarFox, Yoshis Island 2 and Doom, they all worked (tested v3).

 

It is supposed to be running FX games a bit slow, but all NES games in my childhood was running slow so I'm not picky. Im sure it will be sorted out.

Great that someone is taking on this task.

 

Talking of speed..

I sold a PAL NESRGB system to a work college, he said it was broken since the music was running slow on his childhood SMB1. He refused to belive that it was that way back in the day, he was used to play on emulator past 20 years or so in proper NTSC speed.

 

Version 4 is out now and fixes a bug that was introduced in version 3.

 

I remember calling this BS last month as all there was a short video. Whoops! It is real, and it seems like a lot of progress has been made in such a short period of time.

 

Of course people are begging for SA1 support. Not an expert, but from what I read, it is felt that it is probably beyond the capability of the SD2SNES

[cybercylon]

Nice selection of games my friend. Big fan of Parodius...

 

Good idea but without a CPU it may be difficult to write a PNG encoder for the FPGA. Or one could use raw bitmap, but it would require making a 1080p frame buffer of the entire output screen. I don't think there's enough memory as the output resolution (including scanlines and scalars) is generated procedurally in real time. The only thing that's buffered is a few scanlines worth of native pixels. It's not an emulator so emulator specific functions that are easy with a CPU with unlimited resources, might be difficult or impossible to pull off on an FPGA.

 

And yeah what he said, just set the output brightness to zero. How will you know if it's on though???

 

EDIT: 400 pages yay!

 

How about use an HDMI capture device and take stills out of a short movie?

[F34R]

 

Version 4 is out now and fixes a bug that was introduced in version 3.

 

I remember calling this BS last month as all there was a short video. Whoops! It is real, and it seems like a lot of progress has been made in such a short period of time.

 

Of course people are begging for SA1 support. Not an expert, but from what I read, it is felt that it is probably beyond the capability of the SD2SNES

version 05 is out now.

[D3ltax55]

version 05 is out now.

just loaded it up after I got home from work. Seems working fine. everyone wants SA-1 we all know it. After SA-1 maybe put cheats in there. and whatever chip needed. Lets hope SA-1 is even possible since it's a beast of a chip.

Edited April 11, 2018 by D3ltax55

[Andromeda Stardust]

just loaded it up after I got home from work. Seems working fine. everyone wants SA-1 we all know it. After SA-1 maybe put cheats in there. and whatever chip needed. Lets hope SA-1 is even possible since it's a beast of a chip.

Is sa-1 the only expansion chip that explicitly needs the extra pins (besides super gameboy and non-existent msu-1). I noticed some superfx games run without the extra pins connected using a game genie as a passthrough. Sa-1 games absolutely don't work, so the sa-1 is doing more under the hood than fx.

[phoenixdownita]

Is sa-1 the only expansion chip that explicitly needs the extra pins (besides super gameboy and non-existent msu-1). I noticed some superfx games run without the extra pins connected using a game genie as a passthrough. Sa-1 games absolutely don't work, so the sa-1 is doing more under the hood than fx.

https://forums.nesdev.com/viewtopic.php?t=10376&p=117031

 

not so much, but the whole Address Bus B is there.

[Great Hierophant]

Is sa-1 the only expansion chip that explicitly needs the extra pins (besides super gameboy and non-existent msu-1). I noticed some superfx games run without the extra pins connected using a game genie as a passthrough. Sa-1 games absolutely don't work, so the sa-1 is doing more under the hood than fx.

 

Of the Super FX games, only Star Fox needs the expansion connector and only for the clock pin. Other Super FX games have ceramic resonators on their PCBs to provide a clock signal for the Super FX chip. SDD-1 games also need the clock pin. Super Game Boy 1 needs the clock pin and the audio output pins, but the Super Game Boy 2's PCB has a proper clock circuit and does not need that pin. SA-1 games need the refresh pin. the clock pin and sometimes one of the extra address bus pins. Some special chips like the OBC-1 have the extra pins but do not connect any of them.

[phoenixdownita]

It seems krikzz is overhauling the EDN8

http://krikzz.com/forum/index.php?topic=5818.msg57861#msg57861

let's hope he fixes FDS audio and FDS change-side delay .... has FDS support ever been fully fixed on Nt Mini?

[Andromeda Stardust]

 

Of the Super FX games, only Star Fox needs the expansion connector and only for the clock pin. Other Super FX games have ceramic resonators on their PCBs to provide a clock signal for the Super FX chip. SDD-1 games also need the clock pin. Super Game Boy 1 needs the clock pin and the audio output pins, but the Super Game Boy 2's PCB has a proper clock circuit and does not need that pin. SA-1 games need the refresh pin. the clock pin and sometimes one of the extra address bus pins. Some special chips like the OBC-1 have the extra pins but do not connect any of them.

Yeah I actually traced the clock pin on my glop top star fox. My other fx games, the expansion pins are unconnected and the pcb has a crystal on it. I understand Starfox running off the system clock is slower somehow than later games?

 

One potential bnefit to running expansion chips off the hardware clock is being cycle accurate. A very good emulator could record a speedrun and play back the inputs at the controller port of a real system. Any console with independant clock crystals, runs the risk of eventually desyncing due to drift of the clock signal over time. Two consoles or carts won't yeild identical results at the cycle level.

[kevtris]

re: the extra pins, the Super Powerpak uses the entire B bus pins- I think it is the only cartridge that does. It uses it to map the SDRAM when writing to it using 21FFh. I discovered this when getting it to work with the snt. I think something uses every extra pin except for the WRAM enable and the EXPAND pin. So far, I have not found anything using those. Not counting those plug in carts that use the EXPAND pin for video.

[atmn]

It seems krikzz is overhauling the EDN8

http://krikzz.com/forum/index.php?topic=5818.msg57861#msg57861

let's hope he fixes FDS audio and FDS change-side delay .... has FDS support ever been fully fixed on Nt Mini?

 

Whats the problem with the FDS support on the NT mini? The only thing i've heard that's a slight audio difference. Other than that it's OK?

[Riptide]

Whats the problem with the FDS support on the NT mini? The only thing i've heard that's a slight audio difference. Other than that it's OK?

He might be referring to the jailbreak. IE FDS support without the actual FDS.

[Andromeda Stardust]

re: the extra pins, the Super Powerpak uses the entire B bus pins- I think it is the only cartridge that does. It uses it to map the SDRAM when writing to it using 21FFh. I discovered this when getting it to work with the snt. I think something uses every extra pin except for the WRAM enable and the EXPAND pin. So far, I have not found anything using those. Not counting those plug in carts that use the EXPAND pin for video.

 

because im curious, what does the expand pin do? will hooking up a composite signal to this pin (clone system adaptors) risk damage on the super nt or oem hardware?

[D3ltax55]

My super FX cart AIO doesn't have the extra pins that the sd2snes has. Are we talking about those two pins that seem to be extra on the sd2snes? I don't own other carts to know.

[Andromeda Stardust]

My super FX cart AIO doesn't have the extra pins that the sd2snes has. Are we talking about those two pins that seem to be extra on the sd2snes? I don't own other carts to know.

 

Not all expansion coprocessors need the extra pins but some do. None of the DSP carts have the extra pins installed. Super FX doesn't really need the extra pins either, but Star Fox uses the system clock for timing. Later FX games run their own timing crystal (resulting in higher clock speed for the FX chip) but retained the extra pins built into the PCB even though none of them were connected. You could saw them off and games (besides Star Fox) would still work. I may experiment later to see if I can overclock my Star Fox cart. It have the glop tops but considering it sources it's clock signal from the cartridge connector, it would be easy to mod in a new timing crystal.

 

For instance, plug in a Yoshi's Island into a Game Genie and do not enter any codes. The game will boot fine even though the expansion pins on the Game Genie slot are not populated.

[kevtris]

 

 

because im curious, what does the expand pin do? will hooking up a composite signal to this pin (clone system adaptors) risk damage on the super nt or oem hardware?

 

It runs between the cartridge port and the expansion port. It's an input on the super nt, so this won't hurt anything. I am not 100% sure of the purpose, but I suspect just a general purpose signal that a cartridge can use to communicate with something plugged into the expansion port.

 

 

 

 

Not all expansion coprocessors need the extra pins but some do. None of the DSP carts have the extra pins installed. Super FX doesn't really need the extra pins either, but Star Fox uses the system clock for timing. Later FX games run their own timing crystal (resulting in higher clock speed for the FX chip) but retained the extra pins built into the PCB even though none of them were connected. You could saw them off and games (besides Star Fox) would still work. I may experiment later to see if I can overclock my Star Fox cart. It have the glop tops but considering it sources it's clock signal from the cartridge connector, it would be easy to mod in a new timing crystal.

 

For instance, plug in a Yoshi's Island into a Game Genie and do not enter any codes. The game will boot fine even though the expansion pins on the Game Genie slot are not populated.

 

 

Well this is the weird thing. The resonator they use always seems to be 21.47MHz which is the same as the system clock! I am still scratching my head at why they use a separate oscillator that is the same frequency as the system clock. The only thing I can think of is the edge rate or duty cycle or something isn't good enough on all models of SNES/SFC so they made their own secondary oscillator. It also appears that the superFX chip was designed with a crystal oscillator on the chip, but it is broken such that it won't oscillate a crystal or resonator.

 

The crystal oscillator portion of a chip can be real tricky to get right since its params vary depending on process variations and stuff. Even modern stuff is not immune to this problem. Some of the latest PIC micros (the PIC32MZ series) have a broken crystal oscillator and you must use an external oscillator.

 

The clock not being good enough somehow is the only thing I can think of, because they changed the system clock circuit on the SNES several times, starting out with a discrete transistor circuit (similar to the NES) and then tried a 74HCU04 inverter style oscillator. The PAL system has a really nasty clock that has tons of jitter in it because it generates an approximate 21.4MHz clock from a PAL rate crystal using a special "S-CLK" chip.

 

Because they used this oscillator circuit, it makes it relatively easy to boost the clock by simply changing the resonator out with a faster resonator or crystal.

[Andromeda Stardust]

It runs between the cartridge port and the expansion port. It's an input on the super nt, so this won't hurt anything. I am not 100% sure of the purpose, but I suspect just a general purpose signal that a cartridge can use to communicate with something plugged into the expansion port.

 

 

 

Well this is the weird thing. The resonator they use always seems to be 21.47MHz which is the same as the system clock! I am still scratching my head at why they use a separate oscillator that is the same frequency as the system clock. The only thing I can think of is the edge rate or duty cycle or something isn't good enough on all models of SNES/SFC so they made their own secondary oscillator. It also appears that the superFX chip was designed with a crystal oscillator on the chip, but it is broken such that it won't oscillate a crystal or resonator.

 

The crystal oscillator portion of a chip can be real tricky to get right since its params vary depending on process variations and stuff. Even modern stuff is not immune to this problem. Some of the latest PIC micros (the PIC32MZ series) have a broken crystal oscillator and you must use an external oscillator.

 

The clock not being good enough somehow is the only thing I can think of, because they changed the system clock circuit on the SNES several times, starting out with a discrete transistor circuit (similar to the NES) and then tried a 74HCU04 inverter style oscillator. The PAL system has a really nasty clock that has tons of jitter in it because it generates an approximate 21.4MHz clock from a PAL rate crystal using a special "S-CLK" chip.

 

Because they used this oscillator circuit, it makes it relatively easy to boost the clock by simply changing the resonator out with a faster resonator or crystal.

 

kev, i know its a long shot, but any chance the supernt could be updated to enable overclocking either the cpu or the clock pin? i know it could potentially break a lot of games, but people have gone to great lenths to overclock real hardware, so the option to tweak o.c. settings would be fun to play with. the frame rates on star fox are pretty poor irl, and it would be relatively easy to bump up the clock pin using the fpga pll.

[kevtris]

 

 

kev, i know its a long shot, but any chance the supernt could be updated to enable overclocking either the cpu or the clock pin? i know it could potentially break a lot of games, but people have gone to great lenths to overclock real hardware, so the option to tweak o.c. settings would be fun to play with. the frame rates on star fox are pretty poor irl, and it would be relatively easy to bump up the clock pin using the fpga pll.

 

nope, won't happen. Everything must remain synchronous or it will get ugly fast. Sorry 'bout that

[ccovell]

 

Whats the problem with the FDS support on the NT mini? The only thing i've heard that's a slight audio difference. Other than that it's OK?

 

The jailbroken NT mini doesn't play .FDS files yet. For some people (at least myself) when an FDS RAM Adaptor + FDS drive are used with the NT Mini, games fail to boot / load properly:

 

http://atariage.com/forums/topic/242970-fpga-based-videogame-system/page-109?do=findComment&comment=3738175

 

I still have hope that this gets fixed sooner rather than later...

[atmn]

 

The jailbroken NT mini doesn't play .FDS files yet. For some people (at least myself) when an FDS RAM Adaptor + FDS drive are used with the NT Mini, games fail to boot / load properly:

 

http://atariage.com/forums/topic/242970-fpga-based-videogame-system/page-109?do=findComment&comment=3738175

 

I still have hope that this gets fixed sooner rather than later...

 

OK, ye I really hope the Nt Mini get some love soon. Wonderful system.

 

The problem seems to be affecting some revisions of the RAM adaptor only, think ill try to replicate the issue with mine + FDS stick.

[killersquirel]

 

The jailbroken NT mini doesn't play .FDS files yet. For some people (at least myself) when an FDS RAM Adaptor + FDS drive are used with the NT Mini, games fail to boot / load properly:

 

http://atariage.com/forums/topic/242970-fpga-based-videogame-system/page-109?do=findComment&comment=3738175

 

I still have hope that this gets fixed sooner rather than later...

 

I can't get mine to work with the FDS Ram Adapter and FDS emulator stick. Hopefully one day that can be fixed to either play in the jailbreak or with the Ram Adapter + FDS stick.

[spoonman]

Nice selection of games my friend. Big fan of Parodius...

 

Good idea but without a CPU it may be difficult to write a PNG encoder for the FPGA. Or one could use raw bitmap, but it would require making a 1080p frame buffer of the entire output screen. I don't think there's enough memory as the output resolution (including scanlines and scalars) is generated procedurally in real time. The only thing that's buffered is a few scanlines worth of native pixels. It's not an emulator so emulator specific functions that are easy with a CPU with unlimited resources, might be difficult or impossible to pull off on an FPGA.

 

And yeah what he said, just set the output brightness to zero. How will you know if it's on though???

 

EDIT: 400 pages yay!

 

Thanks, I love the Parodius games...and many shooters in general.

 

I'd be fine with 256 color GIF or BMP as well. Maybe it could output the original resolution of 256x224? That should be a tiny file size. I always liked systems that could do this. I installed the developer bios on the original Xbox, just so I could take screen shots with it. Same with the PSP.. Taking 272p resolution images.

 

Perhaps it's possible.. Maybe not. It would be really neat to have though, IMO.

 

 

How about use an HDMI capture device and take stills out of a short movie?

Yeah, that's an option, but if the Super Nt could do it internally that would be much nicer.

[kevtris]

Looks like we hit 10000 posts! I didn't think the thread would get this big, but there it is. Thanks all!