New feature: YPbPr/RGsB output

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Re: New feature: YPbPr/RGsB output

Postby kolla » Wed Jan 18, 2017 2:44 pm

Would it be possible to build a small adapter that allows the use of "regular" cables?
-- kolla

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Wed Jan 18, 2017 3:31 pm

kolla wrote:Would it be possible to build a small adapter that allows the use of "regular" cables?

of course. It's up to you how you will build it: whole cable like i did or just adapter.

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Re: New feature: YPbPr/RGsB output

Postby DrOG » Sun Jan 22, 2017 8:24 pm

Tested the cable, and it works very well! Tried all the cores supporting this feature, and all of them worked fine in progressive mode. Set scandoubler_disable option to 1 my main TV (Samsung LE40B650) had issues with two cores: the fpga64 in NTSC mode, and the Apogee BK-01. In these cases there's and acceptable b&w picture over composite input. The Specialist MX's video flickers if it's set to interlaced. Tried even some cores don't support YPbPr option. There's a visible picture but strong magenta tinted.

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Re: New feature: YPbPr/RGsB output

Postby DrOG » Mon Jan 23, 2017 6:01 am

Made some pictures, so it's easier to compare the different type video outputs.

I used ScreenCap SamyGo application during making these screenshots: it writes to USB the content of the frame buffer.
The app is downloadable here: https://wiki.samygo.tv/index.php5/Conte ... #ScreenCap

Some remarks:

1. I used the NES core for testing, because this is the only one which video output is compatible with all inputs of my TV: VGA, SCART, component progressive, component interlaced, composite, and HDMI (with converter).

2. The HDMI signal was generated using a cheap Chinese 'Mini VGA to HDMI' converter, it's price was 7$ including shipping.

3. Set the parameters of every input on the TV to the same level (brightness, contrast, colour saturation etc...)

4. In case of NTSC signals over component the TV is recognizing the picture as 720x480 in progressive, and 720x240 in interlaced (scandoubler disabled) mode. PAL signals are recognized as 720x576 and 720x576i.

5. Legend for the labels: 'Komponens' means YPbPr, 'AV' is composite (yellow RCA jack), 'HDMI2' is HDMI ;-) , '1. Külső' is SCART RGB, and 'PC' means VGA.

Image

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Mon Jan 23, 2017 10:58 am

Actually 720x240p60 is correct term, while 720x480i60 is not correct. Interlaced mode is when every field has 262.5 lines (total amount for NTSC, not just visible) making total 525. Every field thus is shifted vertically at half line making it really interlaced. True interlaced mode is generated by Minimig core when PAL/NTSC interlaced resolution is selected. All other cores (as far as i know) produce 262 lines per field where each field is actually full progressive frame and fields (in terms of interlaced video) are not shifted by half line like on interlaced video. TV/Monitor/Scaler should correctly distinguish between interlace and progressive because interlaced mode should be processed further to remove interlaced glitches (and reduce frame rate by half), while progressive (240p for NTSC) should be just scaled at full speed.
So, first picture shows correct format 720x240p60.

For cores not supporting YPbPr video, authors should add support. There is two versions of video_mixer.v module exist in my cores. One version (all cores currently except PET2001) has only final mixer and color conversion. Another version (PET2001 in my repository) has all-in-one video processing including OSD, Scandoubler, CRT effect and Color conversion. Both versions are easy to use, and any developer can include it in his core.

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Mon Jan 23, 2017 11:01 am

And yes, Y signal can be used as B/W composite video if color is not required - this is another advantage of YPbPr video.

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Re: New feature: YPbPr/RGsB output

Postby DrOG » Mon Jan 23, 2017 7:02 pm

Thanks for your devoted and far-reaching work! It would be nice if other authors would implement your results in their cores (unfortunately there are some abandoned ones, and some others using non-TV standard video resolutions, i.e. 800x600, or uncompatible refresh rates, i.e. above 70Hz, so I doubt if it's an universal solution).

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Mon Jan 23, 2017 10:32 pm

Those are badly designed cores. I believe all retro systems used standard TV resolutions. My YPbPr solution is for TV resolutions. I hope, later i will be able to use high-end HQ2x saler like in NES core.

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Re: New feature: YPbPr/RGsB output

Postby ericgus » Tue Jan 24, 2017 3:04 am

DrOG wrote:Thanks for your devoted and far-reaching work! It would be nice if other authors would implement your results in their cores (unfortunately there are some abandoned ones, and some others using non-TV standard video resolutions, i.e. 800x600, or uncompatible refresh rates, i.e. above 70Hz, so I doubt if it's an universal solution).


Yea, for example the PlusTOO core is one that needs a lot of work.. the video output on that is notorious to try to find monitors that work. IDK if anyone is even supporting that core.

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Re: New feature: YPbPr/RGsB output

Postby DrOG » Tue Jan 24, 2017 5:18 am

Sorgelig wrote:Those are badly designed cores. I believe all retro systems used standard TV resolutions. My YPbPr solution is for TV resolutions. I hope, later i will be able to use high-end HQ2x saler like in NES core.

I agree, and these cores are the minority. Anyway this is a great progress, keep up your good and important work!

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Re: New feature: YPbPr/RGsB output

Postby vebxenon » Tue Jan 24, 2017 8:18 am

ericgus wrote:
DrOG wrote:Thanks for your devoted and far-reaching work! It would be nice if other authors would implement your results in their cores (unfortunately there are some abandoned ones, and some others using non-TV standard video resolutions, i.e. 800x600, or uncompatible refresh rates, i.e. above 70Hz, so I doubt if it's an universal solution).


Yea, for example the PlusTOO core is one that needs a lot of work.. the video output on that is notorious to try to find monitors that work. IDK if anyone is even supporting that core.


Well, PlusTOO core is open source. I'm not a coder, but somebody of our community could patch or improve it... It was maintained and ported by Till Harbaum, like main Atari ST core, for example. Hope Till will have some time to do some fixes in his cores.

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Re: New feature: YPbPr/RGsB output

Postby RealLarry » Tue Jan 24, 2017 9:17 am

What about the atari800 and atari5200 cores? I think they need some love too.
Source avaiable: http://www.scrameta.net/atarixlfpga_svn/trunk/atari_800xl/
On the other side of the screen, it all looks so easy.

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Re: New feature: YPbPr/RGsB output

Postby vebxenon » Tue Jan 24, 2017 11:42 am

RealLarry wrote:What about the atari800 and atari5200 cores? I think they need some love too.
Source avaiable: http://www.scrameta.net/atarixlfpga_svn/trunk/atari_800xl/


Or Atari 2600, PC Engine, Master System...

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Re: New feature: YPbPr/RGsB output

Postby Newsdee » Tue Jan 24, 2017 1:58 pm

We need to get more FPGA HDL developers. Go befriend your local EE studens :D

Sorgelig, once again this is truly amazing work. I need to give it a try once I fix my MiST power supply...

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Re: New feature: YPbPr/RGsB output

Postby arpalhands » Sat Jan 28, 2017 12:20 am

Hi,

I looked carefully your circuit schematic but I didn't find any wire to ground RCAs.

Do I have to understand that I should not wire any ground RCAs for this circuit? Only the inner connection is required?

Thank you

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Sat Jan 28, 2017 9:55 am

Grounds are shown on circuit. They are pins 6,7,8. And of course they are required for RCA to function.

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Re: New feature: YPbPr/RGsB output

Postby arpalhands » Sat Jan 28, 2017 10:25 am

Yes!

I misunderstood the schematic.
I thought that VGA-1 and VGA-6 was mixed to a single wire on inner point of Pr RCA: I didn't notice the empty circle symbol :(

Sorry for useless disturbance :(

I bought following electronic parts:
http://www.ebay.com/itm/222262304807
http://www.ebay.com/itm/20-x-BC547-Tran ... 0811645527
http://www.dx.com/p/jtron-1-4w-colored- ... pcs-288760
http://www.dx.com/p/diy-25v-100uf-alumi ... pcs-330193

I hope these items will be appropriate to obtain a good video signal.

Thank you for your YPbPr feature. I am very impatient to test it...

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Re: New feature: YPbPr/RGsB output

Postby DrOG » Sat Jan 28, 2017 4:52 pm

I had all day a question on my mind, so I have to ask it:

Is it possible to map the 'ypbpr=1' parameter to the rightmost front button on the MIST? I know it's a core specific button, but it's barely used by any of the cores. Or if it's not possible, to map to the center, like the 'scandoubler_disable=1' option, but with the difference of pressing time or number. I.e. pressing within 1 second shortly two times it would change the RGB<->YPbPr parameter, pressing long the scandoubler, as until now.

It would be very practical, the scandoubler toggler alone is very helpful as well, but combined with the opportunity of selecting RGB/YPbPr it would be even more useful.

We could completely leave out the editing of mist.ini on account of changing the display.

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Sat Jan 28, 2017 5:59 pm

Mapping to right button is unpractical because most (well, all my) cores use this button for reset.
But i was thinking about possibility to switch it somehow. Mostly because i debug my cores and need to switch between modes.
I will think how to make it convenient.

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Re: New feature: YPbPr/RGsB output

Postby DrOG » Sat Jan 28, 2017 6:22 pm

Thanks in advance, this would be a gorgeous feature!

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Re: New feature: YPbPr/RGsB output

Postby RealLarry » Fri Feb 03, 2017 2:42 pm

I'll build and try my own "Sorgeligs cable" the next days - you're so gorgeous, pal!
And for those who can't build/solder: I just ordered a cheap chinese vga->YPbPr adapter https://www.amazon.de/dp/B016KPCTLQ. Will test and report when it arrives in a few weeks.
On the other side of the screen, it all looks so easy.

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Fri Feb 03, 2017 3:33 pm

RealLarry wrote:I just ordered a cheap chinese vga->YPbPr adapter https://www.amazon.de/dp/B016KPCTLQ. Will test and report when it arrives in a few weeks.

It' won't work because it simply outputs RGB signals directly to RCA without any circuit. It's for video cards which do sync mixing inside them self.

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Re: New feature: YPbPr/RGsB output

Postby RealLarry » Fri Feb 03, 2017 4:31 pm

Sorgelig wrote:It' won't work because it simply outputs RGB signals directly to RCA without any circuit. It's for video cards which do sync mixing inside them self.

This might be correct. We will see. There is at least one user comment that the user has to switch the device to YPrBr to make the thing work. Maybe the circuit resides inside the plug. Anyway, it'a cheap test in addiotion to chief's original cable.
On the other side of the screen, it all looks so easy.

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Re: New feature: YPbPr/RGsB output

Postby Sorgelig » Fri Feb 03, 2017 5:04 pm

RealLarry wrote:This might be correct. We will see. There is at least one user comment that the user has to switch the device to YPrBr to make the thing work. Maybe the circuit resides inside the plug. Anyway, it'a cheap test in addiotion to chief's original cable.

I have several scalers which support YPbPr but don't have dedicated YPbPr RCA connectors. These scalers use VGA input for all formats. So i have to use similar RCA->VGA adapter (i've made it by myself) for these scalers.
I have to correct myself: i didn't notice before - this adapter is for display devices (projectors, TVs), not to source devices.

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Re: New feature: YPbPr/RGsB output

Postby RealLarry » Fri Feb 03, 2017 5:19 pm

Sorgelig wrote:this adapter is for display devices (projectors, TVs), not to source devices.

Ha! You're right. Wrong direction: YPbPr->VGA. Dammit :wink:
On the other side of the screen, it all looks so easy.


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