GBS 8200/8220 CFW Project

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strayan
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Re: GBS 8200/8220 CFW Project

Post by strayan »

Kaixe Rho wrote:
fernan1234 wrote:You can try adding a sync combiner such as any cheap Extron RGB interface unit, to get RGBS from the RGBHV output of your DAC[...]

analogue RGBHV output -> Sync combiner -> analogue RGBS output -> GBS-C
Alright, thanks. I think I see now, but how in the world do I connect RGBS to the GBSC, actually? Doesn't RGBS usually take the form of either SCART or Bnc cables with R-G-B-Sync as four separate connectors? There's only the three Y Pb Pr RCA connectors on the GBS that I have.
You buy a BNC to D-sub cable. You use the d-sub (vga) input on the gbs.
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

strayan wrote:
Kaixe Rho wrote:
fernan1234 wrote:You can try adding a sync combiner such as any cheap Extron RGB interface unit, to get RGBS from the RGBHV output of your DAC[...]

analogue RGBHV output -> Sync combiner -> analogue RGBS output -> GBS-C
Alright, thanks. I think I see now, but how in the world do I connect RGBS to the GBSC, actually? Doesn't RGBS usually take the form of either SCART or Bnc cables with R-G-B-Sync as four separate connectors? There's only the three Y Pb Pr RCA connectors on the GBS that I have.
You buy a BNC to D-sub cable. You use the d-sub (vga) input on the gbs.
This cable works well for rgbs. https://www.monoprice.com/product?p_id=568

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fernan1234
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Re: GBS 8200/8220 CFW Project

Post by fernan1234 »

NoAffinity wrote:This cable works well for rgbs. https://www.monoprice.com/product?p_id=568
You can also use the 5-BNC cable, it's often cheaper, and can just leave the V line dangling.
Kaixe Rho
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Re: GBS 8200/8220 CFW Project

Post by Kaixe Rho »

Alright, a couple of things. Going over what has been discussed -

1. RGBHV is VGA and there are questions whether HV should be input into the GBSC. HV can be combined into RGBS through any number of devices, such as an extron box. The only way to connect RGBS to the GBSC is likely through a BNC output from the converter into a BNC -> D-dub (or "VGA,-style") cable.

2. Why this is even being discussed is that as of right now the ONLY device that does quick resolution switching is the GBSC. The OSSC, Retrotinks, and especially the framemeister shit themselves when switching between 240p and 480i or anywhere in the messy in-between zone. The entire tink family, which all take in composite and S-Video, unlike the GBSC, now has a passthrough mode, but I've been having some issues with it, hence the suggestion of the extron box middleman.

Moving on-
However, uh
Considering I threw together the connections I had with what I could find as soon as I found out about the pass through mode had been added, I had never thought to try a different HDMI->VGA adapter. I did, and that completely got rid of the sketchy connection issues when resolution switching. There's a slight bob, now, but the switch is the same every single time, and instantaneous. Which is noteworthy: for PS1 games that people considered unplayable on the other devices (Silent Hill, Chrono Cross), only the menu changed resolutions, and it's not like it impacted gameplay that much. For games like the N64 Resident Evil 2 and other expansion pack heavy games, the resolution might change *constantly*. Very seriously, unplayable, but here is A solution.

That being said, there are still problems, and I assume this is where the RGBHV compatibility comes in.
Here's a picture.
Spoiler
Image
The image is offset to the right and down. I'm guessing this is a problem with, well, horizontal and vertical sync. This was kind of a problem with my Dreamcast before, but this cable also has the extra fun bonus of making everything to the right of the image green.
Now, these problems can be fixed with the horizontal masking and such on the GBSC but they shouldn't be problems in the first place.
I'm going to try ordering a dedicated solid quality HDMI -> VGA cable and try a direct connection between the tink and the GBSC, but I wonder if the only way to get the GBSC to like the image is to, well, not try to input VGA.
fernan1234
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Re: GBS 8200/8220 CFW Project

Post by fernan1234 »

Kaixe Rho wrote:I'm going to try ordering a dedicated solid quality HDMI -> VGA cable and try a direct connection between the tink and the GBSC, but I wonder if the only way to get the GBSC to like the image is to, well, not try to input VGA.
That cable will simply have a built-in DAC just like whatever dongle you're using now, so it won't be any more of a "direct connection" than the dongle + separate cables. But, as you've seen different DACs can have different chips that perform better or worse, so trying a different one can help on that basis alone.

And yeah, not using RGBHV (which generally overlaps with but is not the same as "VGA", but no need to get deep into that) as the input may help as well, at least with the positioning issue.

Also, if this resolution switching is really important to you, there is another option already available now besides the GBS-C, and that is the RT5X. However it is significantly more costly, and you'll have to wait about a month from now for new stock.
Kaixe Rho
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Re: GBS 8200/8220 CFW Project

Post by Kaixe Rho »

fernan1234 wrote:And yeah, not using RGBHV [...] as the input may help as well, at least with the positioning issue.
Well then here's another question.
If anyone sees this: does anyone here use their GBS control with their Dreamcast?
If so, how?
I use mine because [reasons] and have had to make custom profiles for all of my displays because of it. I'm assuming I'm the only one - it seems most people use the dsub input on the GBS board for SCART -> sync stripper -> dsub input, from pictures I've looked up, but I've never owned any SCART cables, so I know nothing about any of that.
fernan1234
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Re: GBS 8200/8220 CFW Project

Post by fernan1234 »

Kaixe Rho wrote:Well then here's another question.
If anyone sees this: does anyone here use their GBS control with their Dreamcast?
If so, how?
I use mine because [reasons] and have had to make custom profiles for all of my displays because of it. I'm assuming I'm the only one - it seems most people use the dsub input on the GBS board for SCART -> sync stripper -> dsub input, from pictures I've looked up, but I've never owned any SCART cables, so I know nothing about any of that.
Most people seem to prefer to use VGA cables or boxes to get 480p out of the Dreamcast and I'm guessing most already had other solutions for that. The GBS-C is mainly used for 240p and 480i inputs, and yeah most people will use SCART to DSub cables. My RGB setup is all DSub already so I don't need to deal with that, and I actually do use my Dreamcast with the GBS-C, but I use a third party VGA cable with a pin lifted so it actually outputs 15khz (480i) RGBHV instead of the default 480p, but I do run it through a sync combiner first since I already had one for use with a CRT monitor.
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

Yes, I play dreamcast 480p vga output through gbs-c, no problems. The only issues I've experienced with vga input is when attempting to downscale. Simply doesnt work well via vga in.

I also personally use scart to a homemade female scart-to-p8 adapter, for all 240p consoles in my arsenal.

No extra combiners, strippers etc ever on the inputs. Just console cable gbs-c. (Notwithstanding my homemade direct connect adapter for the p8 input)

@Kaixe Rho your picture just looks like it needs adjustment. Have you tried tweaking the positional and scaling settings through the ui? I've never once had an image come up centered by default. It always requires adjustment.

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HDgaming42
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Re: GBS 8200/8220 CFW Project

Post by HDgaming42 »

NoAffinity wrote:Yes, I play dreamcast 480p vga output through gbs-c, no problems. The only issues I've experienced with vga input is when attempting to downscale
Came here to ask exactly this. Is the GBS-C supposed to be able to downscale content arriving via the dsub? Or only over component? Because I have two units and component works as expected, but dsub is a mess. I've tried:

various content line doubled via another GBS-C
various content scaled to 480p via a DVDO Edge
various content sacled to 480p via an Extron 301 HD

Both units will only occasionally lock to the signal over dsub, and even then locks looks distorted, as a series of stacked, stretched lines. The webgui will show both the 15kHz downscale AND passthrough lit simultaneously.

I'm hoping I don't have to convert to component to use the downscale feature, and that I'm overlooking something obvious here...

edit: I suppose I can dig out my DVDO VP30 to see if converting to component would in fact solve the issue...though I wouldn't want to use that as a permanent solution due to the added lag.

edit2: found this 50 pages back:
Uh, I suppose I haven't tested the downscale preset with RGBHV :p

The whole RGBHV situation is hard anyway, due to not having the Mode Detect unit.
Each time I fire it up, it is kind of glitchy.
I know why each issue happens, but to fix them all comprehensively, that'll take time.
I thought only the YPbPr output wasn't fully supported yet. Seems either I had that flipped, or RGBHV/RGBS downscaling is also not finalized...
strayan
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Re: GBS 8200/8220 CFW Project

Post by strayan »

HDgaming42 wrote:
NoAffinity wrote:Yes, I play dreamcast 480p vga output through gbs-c, no problems. The only issues I've experienced with vga input is when attempting to downscale
Came here to ask exactly this. Is the GBS-C supposed to be able to downscale content arriving via the dsub? Or only over component? Because I have two units and component works as expected, but dsub is a mess. I've tried:

various content line doubled via another GBS-C
various content scaled to 480p via a DVDO Edge
various content sacled to 480p via an Extron 301 HD

Both units will only occasionally lock to the signal over dsub, and even then locks looks distorted, as a series of stacked, stretched lines. The webgui will show both the 15kHz downscale AND passthrough lit simultaneously.

I'm hoping I don't have to convert to component to use the downscale feature, and that I'm overlooking something obvious here...

edit: I suppose I can dig out my DVDO VP30 to see if converting to component would in fact solve the issue...though I wouldn't want to use that as a permanent solution due to the added lag.

edit2: found this 50 pages back:
Uh, I suppose I haven't tested the downscale preset with RGBHV :p

The whole RGBHV situation is hard anyway, due to not having the Mode Detect unit.
Each time I fire it up, it is kind of glitchy.
I know why each issue happens, but to fix them all comprehensively, that'll take time.
I thought only the YPbPr output wasn't fully supported yet. Seems either I had that flipped, or RGBHV/RGBS downscaling is also not finalized...
You need to combine separate Horizontal and Vertical sync into Composite sync to use the d-sub port for downscaling.

The DVDO can output RGBs via the BNC output so this should work.
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HDgaming42
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Re: GBS 8200/8220 CFW Project

Post by HDgaming42 »

strayan wrote:
HDgaming42 wrote:
NoAffinity wrote:Yes, I play dreamcast 480p vga output through gbs-c, no problems. The only issues I've experienced with vga input is when attempting to downscale
Came here to ask exactly this. Is the GBS-C supposed to be able to downscale content arriving via the dsub? Or only over component? Because I have two units and component works as expected, but dsub is a mess. I've tried:

various content line doubled via another GBS-C
various content scaled to 480p via a DVDO Edge
various content sacled to 480p via an Extron 301 HD

Both units will only occasionally lock to the signal over dsub, and even then locks looks distorted, as a series of stacked, stretched lines. The webgui will show both the 15kHz downscale AND passthrough lit simultaneously.

I'm hoping I don't have to convert to component to use the downscale feature, and that I'm overlooking something obvious here...

edit: I suppose I can dig out my DVDO VP30 to see if converting to component would in fact solve the issue...though I wouldn't want to use that as a permanent solution due to the added lag.

edit2: found this 50 pages back:
Uh, I suppose I haven't tested the downscale preset with RGBHV :p

The whole RGBHV situation is hard anyway, due to not having the Mode Detect unit.
Each time I fire it up, it is kind of glitchy.
I know why each issue happens, but to fix them all comprehensively, that'll take time.
I thought only the YPbPr output wasn't fully supported yet. Seems either I had that flipped, or RGBHV/RGBS downscaling is also not finalized...
You need to combine separate Horizontal and Vertical sync into Composite sync to use the d-sub port for downscaling.

The DVDO can output RGBs via the BNC output so this should work.
Thanks for the info. So downscaling RGBS throught the DE-15 is supposed to work? Just making sure I'm not chasing phantoms...

Will have to attempt tomorrow. My VP30 seems to have it's output setting locked and I can't switch to analog. I'm in "advanced", though that's hardly an advanced function. This is acting buggy as hell TBH...
Ryoandr
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Re: GBS 8200/8220 CFW Project

Post by Ryoandr »

If combining sync at input, downscaling from a 640x480 VGA source absolutely works.
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

To add clarity, there is no difference between rgbs input on the de 15, the 5 pin or the 8 pin. They are all continuous. The de 15 input has the additional sync input. So, any input will get rgbs to the same destination.

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ulfrinn
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Re: GBS 8200/8220 CFW Project

Post by ulfrinn »

Just curious, but what parts of the GBS-8200 and relatives become redundant or unnecessary when the GBS-C device is connected? The Switches I know, the RGB potentiometers. I would pay a little bit more money and do the work (I have the tools for soldering SMD components), and make a new circuit board for the TVIA chip. Does the onboard processor do anything at that point or is it all the ESP8266?
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EmKIronFist
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Re: GBS 8200/8220 CFW Project

Post by EmKIronFist »

ulfrinn wrote:Does the onboard processor do anything at that point or is it all the ESP8266?
It supplies some timing info via the debug pin, people who have broken the debug pin off on accident have successfully removed the entire processor without issues (outside the loss of functionally the debug pin connection provides.) I would consider it essential unless you're only using a GBS Control rig for downscaling or colorspace conversion.
ulfrinn
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Re: GBS 8200/8220 CFW Project

Post by ulfrinn »

I was wondering if any of you guys have an idea about this? In the video before you can see a vertical flicker in the image. It doesn't do it with any other console, and that particular console it does it with was tested for RF, composite, and another RGB upscaler, none of which showed this issue. It's only happening with the GBS. Any ideas?

https://www.youtube.com/watch?v=PVAniFlEYjk
ulfrinn
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Re: GBS 8200/8220 CFW Project

Post by ulfrinn »

EmKIronFist wrote:
ulfrinn wrote:Does the onboard processor do anything at that point or is it all the ESP8266?
It supplies some timing info via the debug pin, people who have broken the debug pin off on accident have successfully removed the entire processor without issues (outside the loss of functionally the debug pin connection provides.) I would consider it essential unless you're only using a GBS Control rig for downscaling or colorspace conversion.
So it still works without it. Is there any other way to get timing besides the debug pin of that chip? And what are we getting the timing values off of? Something from the input signal or from a crystal? I ask because I was designing a circuit board to hold the SCART connector as well as the ESP8266 module, but now I am considering just making a new board for the chip since it seems it and the RAM (input and output as well of course) is all the GBS-C actually needs to function. I even have a damaged GBS board I could get the TVIA chip and RAM from.
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

Someone desperately needs to do a wide release of F to M/M to F DE15 “dongles” with sync combining circuitry within them for the input/also output (if user is downscaling) haha. I know there’s SCART options already, yes. The only downside is that (forget if it is input or output of my unit) combined sync from a powered device like an Extron RGB interface is far more compatible / I have had the video chain’s signal constantly drop sync if both input *and* output implement passive sync combining circuits…

Of course, one could easily just draw extra power for these hypothetical ‘dongles’ from somewhere on the GBS itself while maintaining strong stable sync!
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maxtherabbit
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Re: GBS 8200/8220 CFW Project

Post by maxtherabbit »

Or someone could just rewrite the mode detection logic in GBS-C to handle separate syncs...
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Josh128
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Re: GBS 8200/8220 CFW Project

Post by Josh128 »

Someone needs to write a 1080i/540p mode out. It'll bring lagless gaming to HD era CRTs. Formally requesting it here.
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

maxtherabbit wrote:Or someone could just rewrite the mode detection logic in GBS-C to handle separate syncs...
I don’t foresee that happening before something like what I suggested, haha. I’ve already got my own personal stuff for combining sync but man it’s just endless “explaining RGBHV vs RGBS once more” to so many new people who don’t just use component on these things :O

Also - would “rewriting the mode detection logic” be something that could be implemented to the *output* too? You make it sound like a romp in the park… gonna be hard pressed to find someone who is gonna dive into that, particularly on a niche open source project
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maxtherabbit
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Re: GBS 8200/8220 CFW Project

Post by maxtherabbit »

I have no idea what you're talking about with respect to the output.

The reason that GBS-C struggles with RGBHV inputs is purely a software limitation, the hardware is fully capable. I do not know the degree of difficulty in correcting it though.
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

maxtherabbit wrote:I have no idea what you're talking about with respect to the output.

The reason that GBS-C struggles with RGBHV inputs is purely a software limitation, the hardware is fully capable. I do not know the degree of difficulty in correcting it though.
Output is RGBHV when downscaling to 240p; and you’ll be hard-pressed to find monitors that accept 15kHz RGBHV save for some neat (many of which multiscan) 80s/early 90s PC CRTs. Most people that are using 240p RGB out implement it with shit like PVMs / EuroSCART consumer CRTs - hence the need for combined sync (or, as I said earlier, many of em could just use dang ol component out and call it a day haha)
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Josh128
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Re: GBS 8200/8220 CFW Project

Post by Josh128 »

If you use the component out mode of the GBS, 15KHz downscale is perfectly acceptable by any 15KHz TV with component inputs. No need to worry about output sync for 99% of consumer TVs. You just need a DE-15 to Component cable. I got one off of Ebay that works great for like $7 shipped the other day.
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

Oh yeah, I am well aware! Was referring moreso to the large amount of new kiddos out there dead-set on displaying shit in RGB rather than component, haha. I do happen to have an all-RGB setup at the moment, but as I said before: I got my personal setup squared away RE: sync combining et al… but there’s just so many people asking the same question about HV versus S all the time lately because of this fun CFW :P
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maxtherabbit
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Re: GBS 8200/8220 CFW Project

Post by maxtherabbit »

kitty666cats wrote:
maxtherabbit wrote:I have no idea what you're talking about with respect to the output.

The reason that GBS-C struggles with RGBHV inputs is purely a software limitation, the hardware is fully capable. I do not know the degree of difficulty in correcting it though.
Output is RGBHV when downscaling to 240p; and you’ll be hard-pressed to find monitors that accept 15kHz RGBHV save for some neat (many of which multiscan) 80s/early 90s PC CRTs. Most people that are using 240p RGB out implement it with shit like PVMs / EuroSCART consumer CRTs - hence the need for combined sync (or, as I said earlier, many of em could just use dang ol component out and call it a day haha)
The reason that GBS-C outputs RGBHV has nothing to do at all with input mode-detection

PS many non-sony brand professional video monitors will take 15kHz RGBHV just fine
ulfrinn
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Re: GBS 8200/8220 CFW Project

Post by ulfrinn »

So anyone got any idea why my scaler has that flicker, but only on one specific Sega Genesis that when tested with other RGB scalers, and directly on TVs using composite and RF, works perfectly fine?
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Josh128
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Re: GBS 8200/8220 CFW Project

Post by Josh128 »

Sonic 3, I'll check on mine.
ulfrinn
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Re: GBS 8200/8220 CFW Project

Post by ulfrinn »

Oh it's not just Sonic 3, it's any game on this particular VA4 MD2 Genesis, only over RGB, only on this scaler.
Guile
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Re: GBS 8200/8220 CFW Project

Post by Guile »

Does anyone know if the gbs-c adds any lag if the input is 480p component and 480p rgbhv output?
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