Original analog video without I/O board? Possible!

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Sorgelig
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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Fri Aug 23, 2019 2:17 pm

JamesF wrote:I bought from here (White & Black CM6616):
https://www.ebay.com/itm/HDMI-Female-to ... 3263585349
Notice there are ones with 3 or 4 stripes on the plastic, my CM6616 (Black, White) have 3 stripes.
This has 4 stripes like my Gold:
https://www.ebay.com/itm/1080P-HDMI-Fem ... 3816129491
You may get a AG6200 or CM6616, probably random.

unfortunately both sellers don't ship to Taiwan...


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Re: Original analog video without I/O board? Possible!

Postby JamesF » Sat Aug 24, 2019 10:15 am

Testing the AG6200 adapters with Nvidia video card HDMI output, and all require Limited Range RGB or YCbCr to not crush black shades.

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Re: Original analog video without I/O board? Possible!

Postby gomados » Sat Aug 24, 2019 10:18 am

I tryed new converter and now is working snes cone in my bvm but genesis image is blinking a bit.i got no sync with ossc in some games i see image sometimes sync signall in my ossc is unstable.
can i change something to get other king of sinc signal? i already tried composite and YPbPr on mister.ini fille any suggestions?

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Re: Original analog video without I/O board? Possible!

Postby Lightwave » Sat Aug 24, 2019 3:21 pm

Although a bit dated now, the black crush issue with several of these types of adapters is detailed here:

http://junkerhq.net/xrgb/index.php?title=Analogue_video_output_options_for_OSSC

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Re: Original analog video without I/O board? Possible!

Postby gomados » Sun Aug 25, 2019 2:07 pm

One noob question....
my vga cable has hsync and vsync cables connected to scart pin 20 with a 1kResistor this is correct to display new core with Hdmi direct out?
i have to activate also composite sync=1? thanks for advice.

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Sun Aug 25, 2019 2:43 pm

gomados wrote:One noob question....
my vga cable has hsync and vsync cables connected to scart pin 20 with a 1kResistor this is correct to display new core with Hdmi direct out?
i have to activate also composite sync=1? thanks for advice.


You need to connect only HSync to SCART and enable composite_sync in ini.
But if current setup works fine then no need to change.

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Re: Original analog video without I/O board? Possible!

Postby gomados » Sun Aug 25, 2019 3:07 pm

Sorgelig wrote:
gomados wrote:One noob question....
my vga cable has hsync and vsync cables connected to scart pin 20 with a 1kResistor this is correct to display new core with Hdmi direct out?
i have to activate also composite sync=1? thanks for advice.


You need to connect only HSync to SCART and enable composite_sync in ini.
But if current setup works fine then no need to change.



Many Thanks Sorgelig now is working, i had to change H-PLL Pre-Cost tto o Lines in 0SSC in snes core to stabilize sync.
do you think 1k Resistoor is ok in Hsync or do you think better to solder a 470 intead?

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Sun Aug 25, 2019 10:51 pm

Resistor is not required.

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Re: Original analog video without I/O board? Possible!

Postby jemismyname » Mon Aug 26, 2019 4:31 am

I ordered this ugreen thingy on amazon. should be here tuesday.

https://www.amazon.com/UGREEN-Adapter-C ... B01GFMW91E

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Tue Aug 27, 2019 6:18 am

JamesF wrote:https://www.ebay.com/itm/1080P-HDMI-Female-to-VGA-Male-with-Audio-Output-Cable-Converter-Adapter-Lead-New/352675497682

https://www.ebay.com/itm/US-1080P-HDMI- ... 3842224038

https://www.ebay.com/itm/Robotsky-1080P ... 3256094952

Just buy one black, one gold... it's a lottery anyway.

Received black, white and gold - all are AG6201 (AG6200 with integrated audio DAC).. Ok, will target the Direct Video just for AG620x as most used chip anyway.

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Re: Original analog video without I/O board? Possible!

Postby JamesF » Tue Aug 27, 2019 6:58 am

Yeah AG620x is the most common and doesn't mess with sync signal.
Only problem is it has the limited-range bug, but that's manageable.

AG6201 datasheet:
http://file2.dzsc.com/product/19/06/25/ ... 725655.pdf

Edit:
I've tested the audio with all my vga adapters.
Seems like the "tail" adapters have the cleanest audio and quietest noise floor, especially the UGREEN which has superb build quality.
Probably because the 'tail' adapters are bigger and have more space for better audio dac chips.
The flat (striped white/black/gold) adapters have faint hiss and noise when audio plays.
All support 96kHz.

I recommend this one;
* with audio & power supply port.
https://www.ebay.com/itm/UGREEN-HDMI-to ... 2628627850
The HDMI port on the DE10-Nano provides enough power so no need to externally power these adapters.

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Re: Original analog video without I/O board? Possible!

Postby ono » Tue Aug 27, 2019 9:30 am

Sorry for a completely noob question. I am I right that still everything that goes out of from HDMI port is digital, so there's no risk of "breaking" the display electronics when someone accidentally enables Analog Video mode when connected to HDMI display?
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Re: Original analog video without I/O board? Possible!

Postby JamesF » Tue Aug 27, 2019 10:04 am

Correct. Nothing to worry about.
This is just a very low pixel clock signal that the display/TV will usually ignore or show "out of range".

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Tue Aug 27, 2019 1:32 pm

JamesF wrote:Only problem is it has the limited-range bug, but that's manageable.

it's not a bug. It's a feature.
VGA on I/O board is 6bits per colour which is much more limited (0-63) than 16-240 range.

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Tue Aug 27, 2019 1:35 pm

JamesF wrote:This is just a very low pixel clock signal that the display/TV will usually ignore or show "out of range".

Actually Direct Video uses pixel super-sample. So pixel clock is 80MHz+ in Direct Video where every pixel repeated many times. After VGA converter it becomes clock-less and represents original analog pixels.

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Re: Original analog video without I/O board? Possible!

Postby Lightwave » Tue Aug 27, 2019 1:43 pm

JamesF wrote:I recommend this one;
* with audio & power supply port.
https://www.ebay.com/itm/UGREEN-HDMI-to ... 2628627850
The HDMI port on the DE10-Nano provides enough power so no need to externally power these adapters.


If you scroll down on the page you linked it shows that the UGREEN uses the Chrontel CH7101B. Isn't that the incompatible chip that is also in the Tendak?

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Re: Original analog video without I/O board? Possible!

Postby JamesF » Tue Aug 27, 2019 4:05 pm

Lightwave wrote:If you scroll down on the page you linked it shows that the UGREEN uses the Chrontel CH7101B. Isn't that the incompatible chip that is also in the Tendak?

Yes, but mine came with the newer AG6200.
I think they all come with the AG6200 now.

Sorgelig wrote:
JamesF wrote:Only problem is it has the limited-range bug, but that's manageable.

it's not a bug. It's a feature.

The AG620x doesn't process 0-255 properly, that's why i think it's a bug in the hardware.
It doesn't respect the Quantization Range flag.

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Re: Original analog video without I/O board? Possible!

Postby Sorgelig » Tue Aug 27, 2019 4:27 pm

JamesF wrote:The AG620x doesn't process 0-255 properly, that's why i think it's a bug in the hardware.
It doesn't respect the Quantization Range flag.

Not every device supports both limited and full. Even some TVs support only limited range regardless quantization setting. I didn't see in datasheet AG620x is claimed to support 0-255 range.

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Re: Original analog video without I/O board? Possible!

Postby paulbnl » Tue Aug 27, 2019 5:09 pm

Any HDMI device that does not support Full Range RGB is not compliant to the HDMI specification so that is a defect.

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Re: Original analog video without I/O board? Possible!

Postby JamesF » Tue Aug 27, 2019 5:38 pm

paulbnl wrote:Any HDMI device that does not support Full Range RGB is not compliant to the HDMI specification so that is a defect.

Correct.

Luckily the ADV7513 color space conversion matrices are high bitdepth so there is no truncation artifacts.
From ADV7513 hardware user guide - Color Space Conversion (CSC) Matrix chapter (6.4.3):

Code: Select all

Each coefficient is 13 bit 2’s complement resolution to ensure the signal integrity is maintained.

So people who worry about using the limited_range function in mister.ini and losing bitdepth, there is nothing to worry about, the resulting image quality is just as good as full range.

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Re: Original analog video without I/O board? Possible!

Postby Lightwave » Tue Aug 27, 2019 6:05 pm

JamesF wrote:
Lightwave wrote:If you scroll down on the page you linked it shows that the UGREEN uses the Chrontel CH7101B. Isn't that the incompatible chip that is also in the Tendak?

Yes, but mine came with the newer AG6200.
I think they all come with the AG6200 now.


Ok, just ordered one for testing, hope you are right :)

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Re: Original analog video without I/O board? Possible!

Postby paulbnl » Thu Aug 29, 2019 12:21 pm

JamesF wrote:The AG620x doesn't process 0-255 properly, that's why i think it's a bug in the hardware.
It doesn't respect the Quantization Range flag.


I received the Ugreen adapter. It doesn't process either Limited or Full range properly. It appears that it just always darkens the darkest shades and doesn't change the brighter shades.

The end result is that with Limited range the darkest shades are not crushed but the image is not so bright because white is 235 maximum. I got 225 with the OSSC at default gains. Full Range has correct white level (247 with OSSC) without crushing but crushed darker shades.

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Re: Original analog video without I/O board? Possible!

Postby Lightwave » Fri Aug 30, 2019 12:10 am

paulbnl wrote:
JamesF wrote:The AG620x doesn't process 0-255 properly, that's why i think it's a bug in the hardware.
It doesn't respect the Quantization Range flag.


I received the Ugreen adapter. It doesn't process either Limited or Full range properly. It appears that it just always darkens the darkest shades and doesn't change the brighter shades.

The end result is that with Limited range the darkest shades are not crushed but the image is not so bright because white is 235 maximum. I got 225 with the OSSC at default gains. Full Range has correct white level (247 with OSSC) without crushing but crushed darker shades.


Ah, that’s unfortunate considering I have one on the way. I wish these adapters weren’t so hit and miss.

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Re: Original analog video without I/O board? Possible!

Postby JamesF » Fri Aug 30, 2019 5:30 am

They are all equally miss. :lol:
Yes, using limited range fixes blacks, but whites do not reach 0.7v as they should like paulb-nl said.
There is a 4.7k resistor on pin 35 of the AG6200 that is responsible for RGB swing, this resistor can (should) be lowered to add gain to RGB output to fix that issue.


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