GBS 8200/8220 CFW Project

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rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

I recommend figuring out some configuration that lets your TV accept a 50Hz rate.
If you force it to 60Hz, scrolling will stutter and the games feel just broken.

But sure, you need to decrease htotal to increase the frame rate (going from a 50Hz preset to 60Hz output).
Get the timings first with

Code: Select all

,
then use

Code: Select all

wht x
with x = 20% less than the original htotal.
This should get you a 60Hz picture with several issues. You can fix the issues by resizing all the blanking and/or horizontal zoom.
Once all done, you can save that custom preset, but the timing will correct itself because I haven't implemented automatic correction overrides yet.
I'll probably do this today though.

Edit:
And if that's too much of a hassle, connect via USB, open the Serial Monitor and send the command for the preset you want.

Code: Select all

e
is for 1280x960 @ 60
keremimo
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Re: GBS 8200/8220 CFW Project

Post by keremimo »

rama wrote:I recommend figuring out some configuration that lets your TV accept a 50Hz rate.
It is the Vga to HDMI converter that doesn't accept the 50hz. I scourged the market for a VGA to HDMI converter that actually supports 50hz but no dice unfortunately, they either add extra processing & upscaling potentially screwing up the image or just not accept 50hz at all.

I have a SCART distribution amplifier now splitting SCART pre-GBS, my GBS is only used to route upscaled image to capture card just like a framemeister.

Edit: 1st solution gives a pure green image, second solution does not work even though it sets the preset in serial monitor correctly :(
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Hm, I won't get this done today. if you want to emulate it, comment out line 205 to 226 here:
https://github.com/ramapcsx2/gbs-contro ... ync.h#L205
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orange808
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Re: GBS 8200/8220 CFW Project

Post by orange808 »

keremimo wrote: It is the Vga to HDMI converter that doesn't accept the 50hz. I scourged the market for a VGA to HDMI converter that actually supports 50hz but no dice unfortunately, they either add extra processing & upscaling potentially screwing up the image or just not accept 50hz at all.
https://www.extron.com/product/product. ... =dvcrgbhda
We apologise for the inconvenience
keremimo
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Re: GBS 8200/8220 CFW Project

Post by keremimo »

orange808 wrote:
keremimo wrote: It is the Vga to HDMI converter that doesn't accept the 50hz. I scourged the market for a VGA to HDMI converter that actually supports 50hz but no dice unfortunately, they either add extra processing & upscaling potentially screwing up the image or just not accept 50hz at all.
https://www.extron.com/product/product. ... =dvcrgbhda
420.00 € is the best price I could find from a place that ships to Turkey.

If I could afford something like that, common sense would guide me to buy an OSSC and a PEXHDCAP instead. Please. :roll: If you guys know of any such converter that can be bought on Amazon or Aliexpress for regular human prices instead?

Rama: I did a fallback to the previous working version for now, no worries :) I'll update when it works suitably.
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orange808
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Re: GBS 8200/8220 CFW Project

Post by orange808 »

keremimo wrote:
orange808 wrote:
keremimo wrote: It is the Vga to HDMI converter that doesn't accept the 50hz. I scourged the market for a VGA to HDMI converter that actually supports 50hz but no dice unfortunately, they either add extra processing & upscaling potentially screwing up the image or just not accept 50hz at all.
https://www.extron.com/product/product. ... =dvcrgbhda
420.00 € is the best price I could find from a place that ships to Turkey.

If I could afford something like that, common sense would guide me to buy an OSSC and a PEXHDCAP instead. Please. :roll: If you guys know of any such converter that can be bought on Amazon or Aliexpress for regular human prices instead?

Rama: I did a fallback to the previous working version for now, no worries :) I'll update when it works suitably.
Used equipment has a habit of showing up at reasonable prices. I have one of those Extrons and I paid about $50 usd for it. So, it's about knowing what you want and patience.
We apologise for the inconvenience
keremimo
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Re: GBS 8200/8220 CFW Project

Post by keremimo »

My country does not have paypal, most american sellers do not ship to it either. Combine those with the rarity of the item :) unfortunately not an option.
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Syntax
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Re: GBS 8200/8220 CFW Project

Post by Syntax »

Not sure if anyone else has checked the lag the GBS has but I thought id put it to the test against a consumer CRT and the OSSC.

Its more of a comparison between the CRT and GBS. I cant count the OSSC in this because of the native delay the LCD has.

If I can find another vga cable ill plug the GBS into the LCD at the same time to show how much lag the LCD invokes.


Anyway, below photos are in this order
LG CRT, GBS(Sony VGA Monitor), OSSC(Samsung LCD)
SNES 240p Lag test
Image

As you can see by looking at the numbered circles the GBS only shows less than half a frame of lag behind the LG CRT whilst the OSSC on a decent PC monitor is full frame behind.
TobiasRieper
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Re: GBS 8200/8220 CFW Project

Post by TobiasRieper »

Excellent results there :D our GBS 8200s with the CFW does a pretty decent job. Anyone have any comparison of image quality between the Ossc and GBS CFW? I'm real curious.
Here's my setup:

Image

I've epoxied the wemos D1 to the top of the heatink with a non conductive resin was thinking about using JB weld (the plastic one) but figured it I ever needed to remove the wemos epoxy would be easier to remove.
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orange808
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Re: GBS 8200/8220 CFW Project

Post by orange808 »

@Syntax,
Does that LG CRT have PIP?

I was under the impression that the GBS uses a full frame buffer.
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Syntax
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Re: GBS 8200/8220 CFW Project

Post by Syntax »

The LG CRT has no PIP from memory.
Its a 50hz-60hz model that I have RGB modded.
It should be a pretty good reference for 0 lag.
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maxtherabbit
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Re: GBS 8200/8220 CFW Project

Post by maxtherabbit »

no idea now PIP works, does it normally add lag on tvs that have it even when it's disabled?

those results are very impressive
redcatex
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Re: GBS 8200/8220 CFW Project

Post by redcatex »

Hi i kinda new here. Got a question regarding sync stripping. I built scart adapter with sync strip, but gamecube showed distorted video on stock gbs8220, without striping it kinda worked, so question is does PAL gc not requiring striping sync signal ? Should i just make a switch to turn on/off sync striping for better compabillity.

Other question is, as i understand in cfw we have some kind of software scanlines solution by blanking lines. Does hardware slg still better option for scanlines combined eith cfw ?

Thanks.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Well, that's certainly interesting.
I know that I have the VDS reading from the same frame that's just been written. There is no buffer except for the "drawing board".
This is what makes this design faster than something like the Framemeister, but I didn't know it was that fast.

Anyway, it feels instant, so that's a win :)

The latest presets and websocket stuff is stable, I suppose. I've merged it into master.
Please let me know if something burns.
Thanks :)
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maxtherabbit
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Re: GBS 8200/8220 CFW Project

Post by maxtherabbit »

rama wrote:Well, that's certainly interesting.
I know that I have the VDS reading from the same frame that's just been written. There is no buffer except for the "drawing board".
This is what makes this design faster than something like the Framemeister, but I didn't know it was that fast.

Anyway, it feels instant, so that's a win :)

The latest presets and websocket stuff is stable, I suppose. I've merged it into master.
Please let me know if something burns.
Thanks :)
So if we assume the two CRTs in his test both have " reference level" raster speed (i.e. no digital processing) wouldn't that mean that the GBS would be outputting lines from the frame buffer before the entire frame is buffered? If I'm understanding every thing here correctly that would be the only way that these results could be possible since the second CRT is only a few scanlines behind the first...

If all this is true, and especially if it holds true on the HDMI version of the board it would seem you've made a $30 ossc :P
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Nah, we can't match the purpose made OSSC with a general purpose board like the GBS.
There will always be some compromise due to the extra processing blocks, a little noise from the cheap (missing) input filtering and odd glitches from not fully understanding all the parameter interaction.
Also, depending on the selected options, the picture is a little blurrier for sure.

But if the preset is tuned just right, then it does produce a great image and low lag.
Certainly awesome for the money spent :)
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Truth be told, I don't know at what point VDS reads from the buffer.
Input and output of that buffer is asynchronous and line based, so it is possible for the hardware to go under one frame of lag.
From the behaviour, I'd say it works like computers with a CRT with disabled vsync.
Lines are fed to the buffer unsynchronized with the rate lines are read for output.
Due to scaling, line doubling of the input and htotal (VDS read speed) matching, there's enough new data for the faster output scan rate.
But when input and ouput rates get close to alignment, there's a vertically moving bar.
"Active frametime lock" avoids the bar, though it is tricky to configure and not all displays like the method.
I'll have to work more on that to improve compatibility.

Regarding the lag measurement done by Syntax, I'd like to mention that most late CRTs like the one he used do some digital processing.
It depends on the model what kind of lag that introduces. It could be just a few lines or sometimes entire frames, mostly seen on "100Hz" models.
Chances are good that his CRT has under a frame of lag though.
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Syntax
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Re: GBS 8200/8220 CFW Project

Post by Syntax »

Im able to plug in 2 more CRT from different era and take another shot if its of any use.

Its funny how these things work, If I take a shot with a really fast shutter speed it always shows each screen on the same frame.
4 Screens all exactly the same solid number.

Is this because with a lower shutter speed I get a longer sample time and thus can see the entry and exit points of each frame?
TobiasRieper
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Re: GBS 8200/8220 CFW Project

Post by TobiasRieper »

For the money spent on it the gbs solution rocks. Used to be crap without all the work Rama and others have put in to it. If anyone has an Ossc for comparison or a frame meister that would be really interesting to see. To me this is better than a frame meister as I play alot of games that switch resolution and with this I get no lag or lose sync for few seconds :D
Higgy
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Re: GBS 8200/8220 CFW Project

Post by Higgy »

I was trying out my Dreamcast and PS1 last night on a GBS CFW build from 2 days ago.

The both looked good at 50 & 60Hz. :D I did not use any options via Websettings, just plugged in and played.
keremimo
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Re: GBS 8200/8220 CFW Project

Post by keremimo »

Rama, is it possible to use RGBHV input to upscale DOS games on real hardware? Resolution is generally 320x200 at 70hz as far as I know for most DOS games using the VGA standard.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Yep, that's possible :)

I don't have the glue logic in place to actually make it happen now.
The source search routine needs to be able to work with RGBHV and then test for it in its loop.
Once that works, there'll be half a dozen new video modes to implement.
I sure hope I can make it work with existing presets!

You may find some posts from when I tested this out maybe 5 - 10 pages back in the thread.

In the mean time, here's a nice new option:
https://github.com/ramapcsx2/gbs-contro ... 46a12e312c

Basically, this implements the DCTI feature that replaces slow pixel edges with faster ones.
Image
It improves sharpness and detail, especially if the ADC sampling phase is just a little off, which is very common right now.
The price for that is occasional misdetected edges. I've minimized the glitches those cause, so overall I consider it an improvement.
All optional, of course :)
keremimo
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Re: GBS 8200/8220 CFW Project

Post by keremimo »

rama wrote:Yep, that's possible :)

I don't have the glue logic in place to actually make it happen now.
The source search routine needs to be able to work with RGBHV and then test for it in its loop.
Once that works, there'll be half a dozen new video modes to implement.
I sure hope I can make it work with existing presets!

You may find some posts from when I tested this out maybe 5 - 10 pages back in the thread.

In the mean time, here's a nice new option:
https://github.com/ramapcsx2/gbs-contro ... 46a12e312c

Basically, this implements the DCTI feature that replaces slow pixel edges with faster ones.
Image
It improves sharpness and detail, especially if the ADC sampling phase is just a little off, which is very common right now.
The price for that is occasional misdetected edges. I've minimized the glitches those cause, so overall I consider it an improvement.
All optional, of course :)
I turn this on for PS2 and Dreamcast, but on Amiga the misdetected edges make the small texts very hard to read. Other than that, really nice! The gains are very subtle though as far as I saw.
TobiasRieper
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Re: GBS 8200/8220 CFW Project

Post by TobiasRieper »

I tested out the latest development branch, working perfectly at the moment. I tried your new setting but couldn't see a difference. I'll play around more later. It's brilliant now though i don't need to alter the vertical or horizontal position. It's pretty much just plug and play. Love it :D I can play my old 3d games without them looking completely awful.
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

Glad the newer timing calculation seems to work out well then :)

DCTI is a subtle effect. It works on UV color data only (and not on Y / Luma). Our eyes don't notice imperfections there nearly as much.
Try to focus on a small sprite. An SNES Mario will be great.
Within the sprite, most details are created with colored pixels that are affected by this option.
With DCTI disabled, the horizontal edges of those colored pixels tend to be blurry.
Enabling DCTI replaces the blurry edges with sharp ones.

Overall, the option enhances the "first impression" look of a game, kind of a polish ;p
TobiasRieper
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Re: GBS 8200/8220 CFW Project

Post by TobiasRieper »

Yeah they work perfect. :D it's such a relief not to have to spend a few mins altering the position. I reckon I'll try it on some 2d games. I don't really play snes more of a megadrive kinda guy ;)
rama
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Re: GBS 8200/8220 CFW Project

Post by rama »

rama wrote: The source search routine needs to be able to work with RGBHV and then test for it in its loop.
Once that works, there'll be half a dozen new video modes to implement.
I added a new operation mode that watches for separate H+V sync (VGA).
If it detects such input, the scaler switches into sync bypassing + video sampling direct to the DAC for output again.
It has a few quirks but in this mode, a whole range of VGA timings will just work.

Basically, this turns the GBS into a high tech version of this:
Image

:p
keremimo
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Re: GBS 8200/8220 CFW Project

Post by keremimo »

rama wrote:
rama wrote: The source search routine needs to be able to work with RGBHV and then test for it in its loop.
Once that works, there'll be half a dozen new video modes to implement.
I added a new operation mode that watches for separate H+V sync (VGA).
If it detects such input, the scaler switches into sync bypassing + video sampling direct to the DAC for output again.
It has a few quirks but in this mode, a whole range of VGA timings will just work.

Basically, this turns the GBS into a high tech version of this:
Image

:p
LOL

Great start though! Most televisions probably won't support those 70-75hz modes so I guess next in line is to grab those frames and put them through a 60hz preset, right?
Stremon
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Re: GBS 8200/8220 CFW Project

Post by Stremon »

Hi guys,

So I finally did my first GBS Control setup today, but sadly I just can't make it work.

My GBS 8220 is connected to a Micomsoft XSelect-D4 (a japanese D terminal/RGB/Component selector) though the VGA out, which basically pass-through any RGB or component signal I throw at it.
(the other D terminal output is directly connected to my TV)

With the default 8220 firmware, both the 240p/480i and 480p can be displayed on my monitor (but of course the 240p/480i are not displayed correctly on my LCD).

I now have a NodeMCU, so I connected the 3V, GND, D1, D2, and D6 of it respectively to the VCC, GND, SDL, SDA and debug pin of the 8220.
With the Arduino IDE I tried to flash the NodeMCU with first "NodeMCU 1.0" mode and then reflashed with "WeMos D1 R2 & mini" mode after seeing the comment inside the code.

The problem is that when I power it on, there is no signal at all coming out of the VGA output, no matter what I try.
I can access to the NodeMCU web server, not nothing helps making the output VGA to react.

In the troubleshooting part of the guide, I checked point 1 and 2, but I wonder how to do the 3rd point.
I know my RGB21 (japanese SCART) cables do have a 75/100 resistor inside for the sync, but not sure if it the same thing.
In the Sync part of the guide, it's explained, but despite my efforts trying to understand it and how to do it safely, I really don't know if I need to add some circuit for the sync signal and how/where to do it.
If I understand correctly, the sync circuit should be made for the sync-in, so no matter if it's done of not, I should still have something coming out of the output VGA, right?

Sorry for all those questions, I tried to figure out by myself but couldn't find how to make it work :?

Here is an image of my setup, don't know if it helps:
Image
keremimo
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Re: GBS 8200/8220 CFW Project

Post by keremimo »

Stremon: Just to understand how your switch works, do you get an image when you set the stock firmware on RGBHV mode? That one is not completely implemented yet.

Also, looking at your NodeMCU, it seems that you have not powered it yet? It needs power as well. Connect it to USB or use VIN input & a ground with 5v.
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