New feature: YPbPr/RGsB output

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DanyPPC
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Re: New feature: YPbPr/RGsB output

Post by DanyPPC »

There is a drop frame in scrolling games, like the screen is not well synchronized at 50Hz.
It happens on C64 and Minimig Core.

On Atari ST core the screen is perfectly syncronized in scrolling games, like Giana Sisters STE version.

Old minimig ECS Core is well synchronized, but minimig AGA doesn't.
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Re: New feature: YPbPr/RGsB output

Post by MasterOfGizmo »

DanyPPC wrote:There is a drop frame in scrolling games, like the screen is not well synchronized at 50Hz.
It happens on C64 and Minimig Core.
The MIST does not drop any frames as it doesn't synchronize anything. It's not like an emulator where you need to sync the emulation with the video output of the PC it's running on.

I also see some stuttering with e.g. the Genesis core and my TV. But it's the TV that does the buffering and does the imperfect synchronization. The same core looks perfectly on other screens.

If there's a change between the ECS and AGA cores than the video timing might have changed slightly and you TV just handles it differently. But i must admit that i don't know much about the video of an Amiga.
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DanyPPC
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Re: New feature: YPbPr/RGsB output

Post by DanyPPC »

Ok I understand, thanks for the clarification.
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Re: New feature: YPbPr/RGsB output

Post by seastalker »

Thank you Sorgelig for adding this feature!

I hope to try it out. I currently have hdmi out going to an s-video converter and some of the picture is cut off screen so I am mostly using it on a flat tv outside of this test on my CRT in case a setting could improve the cut-off. On my Component input, My HD Retrovision cable really shines! With all the great Mister addons like cases and even an RTC board, I am still surprised no one has a simple HD-Retrovision quality solution. Am I alone in thinking it would sell like hotcakes?

I have 90s VGA Computer Crts, (even a NEC mutisync), 80's Commodore monitors with 9pin RGB input, and both S-video and Component input CRT tvs and have yet to connect my Mist or Mister to them in an ideal way. I've made Atari cables to connect the serial to USB for disk loading, but prefer not to rely on my hack job for Mist and Mister. Maybe Console5 can put a DIY kit of all the parts needed together. Have any of you made a video making one?

I am open to PM if anyone has a good cable(s) to sell!
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goran
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Re: New feature: YPbPr/RGsB output

Post by goran »

Hi,

So far I used Sony PVM CRT monitor and scandoubler disable for most of the cores other the Arcade cores that require display rotation.
I decided to try ypbpr option though I don't have special ypbpr cable, just simple VGA-RGB cable like this:
Image

To my surpise, it worked! How so? Small circuit mentioned before is not needed or It's working because I use external sync?

I also have a small problem: I have simultaneously connected Samsung LCD monitor via VGA splitter, but it does not display picture unless I disconnect sync cable from the Sony CRT. Any suggestions how to solve this?

Best regards,
Goran
Best regards,
Goran
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Re: New feature: YPbPr/RGsB output

Post by slingshot »

It's working because I use external sync?
Yes, the extra circuit is to mix the sync signal into the Y input.

Btw, you can try the no_csync option in mist.ini with RGB+15kHz and this cable.
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goran
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Re: New feature: YPbPr/RGsB output

Post by goran »

I tried, no noticeable difference on 8bit cores. Will test with MiSTery and minimig.

BTW, I have RGB-H-V cable and I think that the PVM expects composite sync, should I use sync combiner H+V=S?

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Goran
Best regards,
Goran
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Re: New feature: YPbPr/RGsB output

Post by slingshot »

goran wrote:I tried, no noticeable difference on 8bit cores. Will test with MiSTery and minimig.

BTW, I have RGB-H-V cable and I think that the PVM expects composite sync, should I use sync combiner H+V=S?

Best regards,
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Not many 8-bit cores supports that settings yet. Maybe NES (and SNES, I think it's more 8-bit than 16) are the only ones so far. 16 bits are in better shape.
Why the PVM has separate HSYNC and VSYNC inputs then? As I've seen on some picture. The hsync output already composite in 15kHz modes (and without no_csync), no need to mix anything externally.
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Re: New feature: YPbPr/RGsB output

Post by squid4 »

You are connecting using a sync on composite into the PVM? And you've selected "RGB/EXT or COMP/EXT" on the PVM settings?
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goran
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Re: New feature: YPbPr/RGsB output

Post by goran »

Forum ate my reply from this morning. :)
The hsync output already composite in 15kHz modes (and without no_csync), no need to mix anything externally.
Thanks for this, I was already searching for sync combiners. :)
None of the PVMs I saw or own(ed) had separate H and V sync inputs, only one BNC plug for sync. I had one Sony computer monitor with bnc inputs including H and V syncs but it was too big and sadly I sold it.
So, RGBs and YPbPr are working Ok with ext sync. As component video should have sync in Y so I tried with ext sync off in YPbPr mode, but the picture was shifted, with lots of ghosting, wrong levels... As soon as I turned on the ext sync, all good. Am I missing something?

I still have problems with Spectrum core and Pentagon timings. My older PVM-1450QM is displaying the picture OK but It's older and missing some of the features. PVM-14L4 is newer (and has component without hacking, under/overscan...) but can't display Pentagon correctly. I guess It's a bit stricter on the timings. If someone have any suggestions on this, maybe some service settings, I would be thankful.

Best regards,
Goran
Best regards,
Goran
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