NES Composite Output

[mindfiedx]

Hi,
I own a NES PAL Version since I was kid and by playing with Gradius game, there is always been a very cool "shining stars" effect with the original console using both rf or composite output.
I actually have a Mister connected to a 21" 15KHz Trinitron crt with scart RGB using Direct video (which looks superb really defined and firm image!!!) but I've noticed I'm missing the "shining stars" effect. Instead of shining stars I get a orange and blues stars.
So I've tried with a cheap standard hdmi to composite converter (https://www.amazon.it/gp/product/B07PH4K2DC/) to see if it could bring back this effect, now stars are more white but still won't shine. Maybe it's caused by the converter internal conversions and I need a more "real" raw composite output. I've also noticed images are not as firm as when using Direct Video.

Some links found on youtube to get an idea of the effect I'm talking about:

composite/rf
https://www.youtube.com/watch?v=SUIG3hhLD3E

rgb
https://www.youtube.com/watch?v=Wmpi64_RpnE

My questions:

• I'd like to try with Antonio Villena's Composite adapter (https://www.antoniovillena.es/store/pro ... o-adapter/) but I'd like to know first if can bring the composite output as the one I have on NES. Is there anyone owning it who could gently make ths "shining stars" tests? In case would it work with Direct Video?
• Woudn't it be cool, in terms of preservation, to have a native composite out of Mister? Do you think it might be feasible ?

I'd really like to get this out since the composite is what I remember from my childhood both for the blending and the colors (like Metroid) .

Thanks in advance and kind regards to all

[max1602]

Hey, I‘m very interested in this too.
Never seen that adapter. Would love to get aslightly rougher picture out of mister.
Maybe a bit of an esoteric wish hahaha

[Jegriva]

I think that effect is created by composite video artifacts, it might require a bit of work to recreate them in the RGB/digital signal of the Mister.

The Genesis/Mega Druve core has a "composite effect", that might work if implemented in the Nes core. Maybe.

[jlancaster86]

- Woudn't it be cool, in terms of preservation, to have a native composite out of Mister? Do you think it might be feasible ?

Honestly, I think an external RGB-to-composite adaptor is likely to be as good as it gets. I can't imagine there'd be enough demand to make an I/O board with composite output, and I imagine it would essentially be the same circuitry as the external solution anyway.

Composite-style filter effects may be more likely, but again, there probably isn't enough demand to justify the work.

[barfood]

I have AV's adapter, I'll try to capture and share the test results tonight.

[keilmillerjr]

I vote for composite/svideo on analog hat. Anyone in USA with crt would greatly appreciate it.

[mindfiedx]

I have AV's adapter, I'll try to capture and share the test results tonight.

Thanks, it would be great!

[barfood]

I have AV's adapter, I'll try to capture and share the test results tonight.

Thanks, it would be great!

Here you go! The video is still processing, but by the time you see this post it should be viewable: https://youtu.be/4kIeOnPOVd0

Please forgive the rough filmography, hopefully it provides the insight you were looking for. From my eyes, the answer seems to be: no, the stars in the background of Gradius do not flicker as much on the MiSTer's composite signal as the original NES (or, in my case, the AV Famicom).

I noticed after recording that the palette I used on MiSTer was Pixeltao v2, which is not the most color accurate when compared to real hardware (hence you will notice differences in colors when I switch from one signal to the next). However, I doubt this is the source of the difference when it comes to the flickering stars.

[mindfiedx]

Great Video Thanks!
looks like the color blending is still more present on famicom (I can still distinguish the orange/blue stars on Mister while famicom's are more whitish), btw the AV's vga->composite converter looks way better than my cheap hdmi-> composite.
@keilmillerjr yes I also think it would be great to have it on analog hat. I live in europe but composite feeling is too way nostalgic

[max1602]

Has there always been a vga to composite adapter?
Or is it a new thing?
Has it been made specifically to downgrade the mister signal?

[barfood]

Has there always been a vga to composite adapter?
Or is it a new thing?
Has it been made specifically to downgrade the mister signal?

It has been available for some time from https://www.antoniovillena.es/store/pro ... o-adapter/, however it should be noted that this adapter currently generates inaccuracies in the composite signal due to -some- mismatch in signals that causes "moving dot crawls" due to disagreements in how this signal should be implemented between Antonio and the MiSTer repo owners. I won't try to be more specific not to give false information, but you can probably find discussion on this forum regarding this specific adapter (e.g.: viewtopic.php?f=29&t=1068&p=10440#p10440, https://www.atari-forum.com/viewtopic.php?t=37611)

[mindfiedx]

@barfood, btw from you video it looked like your mister composite was very good. Are you experiencing "moving dot crawls" with the AV's adapter?
Some hours ago I've ordered one but after reading those long thread I'm confused. Is there any video showing that? I mean I've found a relative recent video about it (1 month ago) that looks very promising and image looks very still I havent noticed any moving dot crawls: https://www.youtube.com/watch?v=FU41X9_zcbQ
https://www.youtube.com/watch?v=lnXKFwwIh58
Is there a new version ?

[barfood]

@barfood, btw from you video it looked like your mister composite was very good. Are you experiencing "moving dot crawls" with the AV's adapter?
Some hours ago I've ordered one but after reading those long thread I'm confused. Is there any video showing that? I mean I've found a relative recent video about it (1 month ago) that looks very promising and image looks very still I havent noticed any moving dot crawls: https://www.youtube.com/watch?v=FU41X9_zcbQ
https://www.youtube.com/watch?v=lnXKFwwIh58
Is there a new version ?

What I have is the first (and I believe only) version of the adapter. As the video rightly states, the dot crawl is most easily observed on the red color. Though faint, for example you would never notice it in the middle of gameplay, it does show on title screens. Maybe you'll never see it: if so, great! It's really subtle, honestly.

I don't think it's bad enough to prevent a buy, it's just worth knowing about beforehand. Interestingly, the S-video connection is free of that dot crawl effect. Thus, if possible, that is the signal I would recommend if you end up getting this adapter.

[max1602]

Thanks for the answers.
It's so ironic that I crave for a rougher picture output from mister. Taking into account so many people strive for rgb-modded console perfection.

But roughening things up now and again can just be a pleasure...

[mindfiedx]

After asking some questions to @antoniovillena he told me the adapter is a new version that mitigate the problem but that the problem is there and it occurs with all vga->composite adapters. Moreover it has clock detection on VSYNC pin. If a clock is detected this clock override the PAL or NTSC crystals. @antoniovillena has also been very kind suggesting me to ask in the forum to hear third opinions so If I have doubts after that he can cancel the order.
My final thoughs are that at the state of art this is actually the best compromise for me to get composite on Mister. If one day Mister Fpga cores would generate this clock on VSYNC pin the adapter would automatically work using that clock and avoiding the "moving dot crawls" behaviour so I wouldn't have the need of replace it with a new one. That said i think I'll proceed with getting the adapter and give it a chance .

A note about the video https://www.youtube.com/watch?v=lnXKFwwIh58
Looks to me video shows some "moving dot crawls" with red when showing miser side at 7:41 . Moreover seems to me like that behaviour is not present on rpi (7:48) ?

Thanks again for the kind way you are supporting me on this composite journey

[paulbnl]

Moreover it has clock detection on VSYNC pin. If a clock is detected this clock override the PAL or NTSC crystals.

Does the current version that he sells have that or is that in a future version? I don't see anything about that in the description on his shop.

[mindfiedx]

Moreover it has clock detection on VSYNC pin. If a clock is detected this clock override the PAL or NTSC crystals.

Does the current version that he sells have that or is that in a future version? I don't see anything about that in the description on his shop.

Yes, he told me via email that the version is actually selling does have it. Maybe you can write him asking for more details.

[barfood]

Moreover it has clock detection on VSYNC pin. If a clock is detected this clock override the PAL or NTSC crystals.

Does the current version that he sells have that or is that in a future version? I don't see anything about that in the description on his shop.

Yes, he told me via email that the version is actually selling does have it. Maybe you can write him asking for more details.

Any idea on how to tell the versions apart? All I can see on my adapter is "AntonionVillena 2019".

[paulbnl]

Moreover it has clock detection on VSYNC pin. If a clock is detected this clock override the PAL or NTSC crystals.
If one day Mister Fpga cores would generate this clock on VSYNC pin the adapter would automatically work using that clock and avoiding the "moving dot crawls" behaviour so I wouldn't have the need of replace it with a new one.

I bought Antonio's VGA->Composite adapter after he confirmed that the clock override would work on his current model.

Unfortunately he failed to mention that he never tested this on MiSTer, only on his ZXDOS board.

I modified some cores to send the clock to the VSync pin but unfortunately it doesn't work at all.

Antonio is reluctant to help fix this because he says he doesn't have time and he says it works on the ZXDOS board so it should work on MiSTer. Thus he is implying that I am not generating the clock correctly.

I asked him 2 weeks ago if he could verify with an oscilloscope that the clock on the VSync signal is correct but he didn't answer me anymore.

[antoniovillena]

Moreover it has clock detection on VSYNC pin. If a clock is detected this clock override the PAL or NTSC crystals.
If one day Mister Fpga cores would generate this clock on VSYNC pin the adapter would automatically work using that clock and avoiding the "moving dot crawls" behaviour so I wouldn't have the need of replace it with a new one.

I bought Antonio's VGA->Composite adapter after he confirmed that the clock override would work on his current model.

Unfortunately he failed to mention that he never tested this on MiSTer, only on his ZXDOS board.

I modified some cores to send the clock to the VSync pin but unfortunately it doesn't work at all.

Antonio is reluctant to help fix this because he says he doesn't have time and he says it works on the ZXDOS board so it should work on MiSTer. Thus he is implying that I am not generating the clock correctly.

I asked him 2 weeks ago if he could verify with an oscilloscope that the clock on the VSync signal is correct but he didn't answer me anymore.

Hi

I have answered all your emails. The ZXDOS board has exactly the same circuit for video DAC. Also I have tried the clock detecting circuit during the prototype phase. So using an external clock on VSYNC override the internal crystals.

[paulbnl]

I have answered all your emails. The ZXDOS board has exactly the same circuit for video DAC. Also I have tried the clock detecting circuit during the prototype phase. So using an external clock on VSYNC override the internal crystals.

You haven't answered the last email I sent you 2 weeks ago where I asked you to check the clock signal on the VSync pin with an oscilloscope.

I have added an 14.31818Mhz clock to the PLL in the SNES core and sent it to the VSync pin. Why doesn't it work?

[antoniovillena]

You haven't answered the last email I sent you 2 weeks ago where I asked you to check the clock signal on the VSync pin with an oscilloscope.

I have added an 14.31818Mhz clock to the PLL in the SNES core and sent it to the VSync pin. Why doesn't it work?

It's not a good clock. You can check with an oscilloscope. You can try with a proper one for example with an external oscillator and this will work

[paulbnl]

It's not a good clock. You can check with an oscilloscope. You can try with a proper one for example with an external oscillator and this will work

Did you actually check the clock with an oscilloscope or did you just guess?

There is no reason for it to be a bad clock because it is coming directly from the PLL. Unless the VSync line has interference on the MiSTer IO board that the ZXDOS board doesn't have.

If there is someone here that has the time and equipment to check the clock on Vsync from the MiSTer IO board then reply here and I will post the modified core.

[antoniovillena]

Did you actually check the clock with an oscilloscope or did you just guess?

There is no reason for it to be a bad clock because it is coming directly from the PLL. Unless the VSync line has interference on the MiSTer IO board that the ZXDOS board doesn't have.

If there is someone here that has the time and equipment to check the clock on Vsync from the MiSTer IO board then reply here and I will post the modified core.

I have checked your core and the image was shaky

[kalach.x]

Here you go! The video is still processing, but by the time you see this post it should be viewable: https://youtu.be/4kIeOnPOVd0

Please forgive the rough filmography, hopefully it provides the insight you were looking for. From my eyes, the answer seems to be: no, the stars in the background of Gradius do not flicker as much on the MiSTer's composite signal as the original NES (or, in my case, the AV Famicom).

I checked Gradius on Twin Famicom which is Famicom version made by Sharp and SONY PVM 14M2E and it actually looks more similar to your Mister version. Stars are clearly made from blue/yellow dots and barely flicker. Pixels on rocks are quite clear and not flickery like on your AV Famicom video.

I do not have AV Famicom myself to check the difference vs Twin Famicom unfortunately.
Differences can be in display or consoles or PPU chip revision.
As for the display changing aperture or 358 trap filter setting doesn't change all that much when it comes to making stars white and flickery. I would assume Sharp uses better components in video amplification signal path. So far it is the best looking "NES" I owned. I prefer it over anything else including even sharper Mister's RGB output.

If Mister's composite adapters can give similar result then this would be something I'd be interested in. Though imho it is needless expense. There are better ways of achieving Composite output I can think of.

[mindfiedx]

Has anyone got the chance to check out the Gradius stars with the new composite cores /boards from MikeS ?

[KennyL]

Has anyone got the chance to check out the Gradius stars with the new composite cores /boards from MikeS ?

Sadly stars don't sparkle on NESYC with Misteraddons active Y/C board. Stars are also blue and orange. Too clean ha! It's really too bad. I love these kinds of noisy signal artifacts that "enhance" the visual so this is unfortunate heh.... But Y/C composite stuff look super nice in general.

[Wave]

I have been wondering if some of the Y/C cores look cleaner than the original hardware. I've seen it suggested that is the case for NES.

[dmckean]

Composite video is just generally crappy and MikeS handles it the best way possible by using a luma trap and careful tuning in the cores to combine Y&C. To handle it the way the NES does natively, you're going to need to rewrite part of the core and need a different analog board that would output at the required levels to be in spec with NTSC and PAL. The end result will be worse for 99% of NES games as there's only a small handful that take advantage of artifacting at all.

[KennyL]

Mikes' tuning of composite is fantastic and look cleaner than real consoles for many cores. Most definitely not crappy. Wii composite is even cleaner. But they are certainly not accurate. Composite look different even between different models of FC/NES. Even more so on RF. I'd love to see someone go sicko mode and come up with MDFourier style measurements for video signals that could be use for simulating different model variants.