GBS 8200/8220 CFW Project

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SCARTicus
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Re: GBS 8200/8220 CFW Project

Post by SCARTicus »

Yeah, I don't understand it either, but the VSC works fine for its intended purpose.
Lee wrote:Anyone else having trouble getting their SFC/SNES to sync properly? I can't seem to get rid of these occasional jitters that happen anywhere from every 30 seconds to every few minutes where the GBS appears to briefly lose sync. Tried csync as well as luma sync, no difference. When I try the console on my RGB Scart equipped CRT it works without any issues.

My GBS is a V4.0, has a 100 Ohm resistor between sync & ground, as well as a clockgen, C11 replaced, extra bypass caps and the RGB pots replaced with direct links. This is also the only console I'm having this problem with, my PS1, PS2, Wii and N64 are all working perfectly.

Hope someone knows what I'm missing.
Does your SNES have a dejitter mod? The SNES and NES have notoriously jittery signals, and the OSSC and other digital devices have trouble with their output. I haven't had any trouble with my SNES, but mine is a model 2 with the RGB/dejitter mod. Are you upscaling or transcoding?
Lee
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Re: GBS 8200/8220 CFW Project

Post by Lee »

SCARTicus wrote:Does your SNES have a dejitter mod? The SNES and NES have notoriously jittery signals, and the OSSC and other digital devices have trouble with their output. I haven't had any trouble with my SNES, but mine is a model 2 with the RGB/dejitter mod. Are you upscaling or transcoding?
Upscaling.
I'll be honest, I completely forgot about the dejitter mod even being a thing, probably since I've never had any trouble on my CRT and never having used any scaler before. Thank you very much, this should be exactly what I need!
jdubs
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Re: GBS 8200/8220 CFW Project

Post by jdubs »

kitty666cats wrote:I think I've said it before but I will say it again: if you feed a scan converter VGA/480p for 480i RGBS out, THEN send it into the GBS for downscaling, it should take care of any issues people are having.
Does it need to go through the scan converter first? I tried 480i from my xbox 360 into the GBS and it didn't work (same rolling picture issue I've been having).

-Jim
immaburr
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Re: GBS 8200/8220 CFW Project

Post by immaburr »

So I abandoned the Scart to VGA card and am using the Scart2DVI from Insurrection Industries as an input into the GBS8200 and output VGA to OSSC

I was actually able to get a signal! But I noticed that the D1 Mini board gets extremely hot - not only that but the blue LED only appears to light up when a signal is active.

Is this potentially bad wiring? I don't want to burn up any electronics.
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SCARTicus
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Re: GBS 8200/8220 CFW Project

Post by SCARTicus »

immaburr wrote:So I abandoned the Scart to VGA card and am using the Scart2DVI from Insurrection Industries as an input into the GBS8200 and output VGA to OSSC

I was actually able to get a signal! But I noticed that the D1 Mini board gets extremely hot - not only that but the blue LED only appears to light up when a signal is active.

Is this potentially bad wiring? I don't want to burn up any electronics.
Yes it is bad wiring. Connect the SCART cable directly to input 1 on the OSSC, ya goof!
immaburr
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Re: GBS 8200/8220 CFW Project

Post by immaburr »

Yes it is bad wiring. Connect the SCART cable directly to input 1 on the OSSC, ya goof!
My config is Consoles connecting to GSCARTSW - Scart2DVI - Converted to VGA into the Input of the GBS8200 - Output is VGA going into the OSSC and OSSC outputting via HDMI.

I'm trying to take advantage of the GBS' ability to buffer out 480i - 240p swaps that's why it's in the mix and not going directly to the OSSC.

Image for reference: https://imgur.com/DwKZZuA
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

To answer one of your other questions, the esp led only lights when an active signal is present.

I just got my hands on a used gbs-8220. Did all the standard mods and clock gen. Didnt do the pump decoupling mods. I also havent done copper tape on it. The image seems solid and stable, better than any of the 8200's I've dealt with (at least 5 or 6).

Image
Image
Image
Image
rememberizer
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Re: GBS 8200/8220 CFW Project

Post by rememberizer »

So this has really been driving me nuts lately. I have been using the GBS Control quite comfortably on my supergun setup, with a video and sound splitter in between the board and the jamma harness. The splitter attenuates the signals to 75ohm levels using a THS7374 for RGB and a LM1881 for sync clamping. It works flawlessly on my supergun, but when I run the splitter on Aero City arcade cabinets, I get frequent split second desyncs. They are much more frequent on the CPS2 than on Neogeo MVS, but they happen using both boards and Namco System 12.

The log outputs this stuff:

Code: Select all

.
. (debug) ign. length: 0x51
.. (debug) ign. length: 0x51
. (debug) ign. length: 0x51

. (debug) ign. length: 0x51
. (debug) ign. length: 0x51

. (debug) ign. length: 0x51
. (debug) ign. length: 0x50
.* (debug) ign. length: 0x51
.
. (debug) ign. length: 0x1A
 (debug) ign. length: 0x51
It prints one of those lines whenever I get a big desync. I've measured the sync line voltage to be around 0.373v on my supergun and 0.399 on the cab. I don't understand why this is happening at all, and any ideas about how to get stable sync on cabs will be much appreciated! edit: forgot to mention, this is without the 100ohm resistor.
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

I used a etim av-driver in my aero city to split jamma, and would get very infrequent blips as well. The av-driver also attenuated to 75ohm, and I used it to split pcb signal out to the gbs for capturing from the cab. My blips were maybe one per 7 minutes on average, but they still occurred. That was with the 100 ohm resistor. I'm guessing its some minor fine tuning within the firmware or the trade off that rama has spoken about, to get compatibility with many or all consoles, there will be some edge use cases that do not work perfectly.

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rememberizer
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Re: GBS 8200/8220 CFW Project

Post by rememberizer »

What gets me is that this only happens on the cabinet and not on the supergun. I even tried directly connecting GBS sync to the sync on the jamma edge with no attenuation and it works on the supergun. I don't think this has much to do with attenuation at this point since I tried to add a 2k pot on the sync line after the lm1881 and it's still not stable no matter what level I set it to. :(

edit: YEAH, I tried it on a Versus City and it works perfectly. :?: :?: :?: :?:
immaburr
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Re: GBS 8200/8220 CFW Project

Post by immaburr »

Finally got it all working. I'm still messing around with connectors for consolidation and integration into my setup. But I'm so damn happy that everything's working now!

Lego GBS:

Spoiler
ImageImageImage
Last edited by immaburr on Sat Sep 19, 2020 9:47 pm, edited 1 time in total.
Jon Nielsen
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Re: GBS 8200/8220 CFW Project

Post by Jon Nielsen »

Thanks a lot for this project and all the information in this thread.

I did the recommended mods and used a SCART-to-BNC board for input. The results are fantastic.

Until today it was hosted in a big lunchbox. Here's the case I just fitted it in. It's two pieces of black zinc cut and folded to slide together. Now I won't mind having it on the shelf below my SCART switch :-)
Spoiler
Image
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djc5166
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Re: GBS 8200/8220 CFW Project

Post by djc5166 »

https://www.ebay.com/itm/SCART-to-GBS-8 ... 2797616350

Has anyone used this to get SCART RGBs into the GBS? Seems like a pretty convenient solution if it works well.
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Gunstar
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Re: GBS 8200/8220 CFW Project

Post by Gunstar »

@NoAffinity - Same, got an 8220 without the decoupling mod and it's pretty solid. I think rama said it's his favourite model? PS I need to try out your wifi aerial mod!

@immaburr/Jon - Interesting cases!
djc5166 wrote:https://www.ebay.com/itm/SCART-to-GBS-8 ... 2797616350

Has anyone used this to get SCART RGBs into the GBS? Seems like a pretty convenient solution if it works well.
flynnsbit uses one: viewtopic.php?p=1418227#p1418227

I'm assuming GBS is fine with Luma and Combined Video Sync if there's no sync cleaner on these.
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

Gunstar wrote:I'm assuming GBS is fine with Luma and Combined Video Sync if there's no sync cleaner on these.
yes, works great with both. csync (composite/combined...not sync over composite...) is the preferred sync option. But gbs works with all.
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Gunstar
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Re: GBS 8200/8220 CFW Project

Post by Gunstar »

NoAffinity wrote:
Gunstar wrote:I'm assuming GBS is fine with Luma and Combined Video Sync if there's no sync cleaner on these.
yes, works great with both. csync (composite/combined...not sync over composite...) is the preferred sync option. But gbs works with all.
That's good to know, thanks.
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djc5166
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Re: GBS 8200/8220 CFW Project

Post by djc5166 »

NoAffinity wrote:
Gunstar wrote:I'm assuming GBS is fine with Luma and Combined Video Sync if there's no sync cleaner on these.
yes, works great with both. csync (composite/combined...not sync over composite...) is the preferred sync option. But gbs works with all.
I think all my sources are or modded to be CSync at this point, but good to know.
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

NoAffinity wrote:
Gunstar wrote:I'm assuming GBS is fine with Luma and Combined Video Sync if there's no sync cleaner on these.
yes, works great with both. csync (composite/combined...not sync over composite...) is the preferred sync option. But gbs works with all.
Oh dang, really? I haven't tried connecting a SHART cable with sync over composite video/luma sync, I had just naturally assumed the thing only took RGBS or RGBHV on the DE15 in. Neat!
eromiya
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Re: GBS 8200/8220 CFW Project

Post by eromiya »

flynnsbit wrote:I tried out the no-solder mod for the GBS-Control for the fun of it. I really don't think it is worth it as the 44 pin socket is snug, but there is a good chance for it to unseat from the chip. I hit it with some hotglue just to keep the PLCC Socket in place. I guess if you had zero soldering experince then it might give you an option. I feel like if you are looking into GBS-Control then you are most likely a tinker-er/Maker and can probably solder 5 pins. I think I will just solder the next one.

Anyway, here are the pics.
Image
Image
Is the Debug pin misaligned?
Jon Nielsen
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Re: GBS 8200/8220 CFW Project

Post by Jon Nielsen »

Gunstar wrote:@NoAffinity - Same, got an 8220 without the decoupling mod and it's pretty solid. I think rama said it's his favourite model? PS I need to try out your wifi aerial mod!
Did you do anything else to make your 8220 solid? I have a 8220 board that wasn't put to use yet because the 8200 I found was so much better.
Gunstar wrote: @immaburr/Jon - Interesting cases!
:-)
Gunstar wrote:
djc5166 wrote:https://www.ebay.com/itm/SCART-to-GBS-8 ... 2797616350

Has anyone used this to get SCART RGBs into the GBS? Seems like a pretty convenient solution if it works well.
Looks very interesting. And it reminds me that I forgot to feed 5V to the sync stripper on the scart input solution that was quickly hacked together :-)
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djc5166
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Re: GBS 8200/8220 CFW Project

Post by djc5166 »

kitty666cats wrote:
NoAffinity wrote:
Gunstar wrote:I'm assuming GBS is fine with Luma and Combined Video Sync if there's no sync cleaner on these.
yes, works great with both. csync (composite/combined...not sync over composite...) is the preferred sync option. But gbs works with all.
Oh dang, really? I haven't tried connecting a SHART cable with sync over composite video/luma sync, I had just naturally assumed the thing only took RGBS or RGBHV on the DE15 in. Neat!
The way the gbs-control github page reads for scart input, I thought it sounded like only CSync was supported, extra bonus if they all are.
rememberizer
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Re: GBS 8200/8220 CFW Project

Post by rememberizer »

NoAffinity wrote:I used a etim av-driver in my aero city to split jamma, and would get very infrequent blips as well. The av-driver also attenuated to 75ohm, and I used it to split pcb signal out to the gbs for capturing from the cab. My blips were maybe one per 7 minutes on average, but they still occurred. That was with the 100 ohm resistor. I'm guessing its some minor fine tuning within the firmware or the trade off that rama has spoken about, to get compatibility with many or all consoles, there will be some edge use cases that do not work perfectly.

Sent from my SM-G955U using Tapatalk

Hey man I actually solved the issue with the Aero City. I can get them to sync perfectly now. With the help of a gentleman from FB arcade groups, I found that completely disconnecting the monitor makes it sync correctly. The chassis might be messing with the signal! So the trick is to not tap both sync outputs on the same point.

This is the way I got it to work: I have my GBS sync coming from the LM1881 circuit, and the sync to cab coming from the THS7374 output. FINALLY a working capture from the Aero!!!
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

djc5166 wrote:
kitty666cats wrote:
NoAffinity wrote: yes, works great with both. csync (composite/combined...not sync over composite...) is the preferred sync option. But gbs works with all.
Oh dang, really? I haven't tried connecting a SHART cable with sync over composite video/luma sync, I had just naturally assumed the thing only took RGBS or RGBHV on the DE15 in. Neat!
The way the gbs-control github page reads for scart input, I thought it sounded like only CSync was supported, extra bonus if they all are.
My saturn is most definitely sync on luma and I've been playing it regularly for the last 3 days via gbs 8220 with no problem. Rama has said many times that an external sync stripper is not needed because the internal sync stripper works well.

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500_pts
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Re: GBS 8200/8220 CFW Project

Post by 500_pts »

So, admittedly I didnt thoroughly scrape this thread to check if this issue has been seen/addressed. Anyways, assembly and installation seem to have gone mostly fine, and pretty much everything works as I expected (haven't installed a clock yet), except when it comes to downscaling 31khz vga to 15khz vga. For whatever reason I get horrible artifacting seen here: https://imgur.com/a/Zz74jgi (green lines on one side, shimmering/shaking image) when downscaling, and after fiddling with the options for a few hours, I've come here to ask if anyone has any insight as to what might be causing this. I tried a ps2 on the component inputs and that seemed to downscale to 15khz just fine, so I assume its specific to the vga input. Thanks in advance for any help!
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

You guys dont have to scrape every page just maybe the last 5 pages.

VGA DOWNSCALING DOES NOT WORK!!!

Sorry to yell but maybe now it's been said loud enough that this same thing stops popping up weekly from new adopters. :)

I think theres speculation about sync combining and then it may work but not sure that's been fully validated.

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Ryoandr
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Re: GBS 8200/8220 CFW Project

Post by Ryoandr »

More like, RGBHV downscaling doesn't work.

RGBS 640x480 (with proper combined sync, 74LS86 circuit) definitively works, tested. (Yes, RGBS over VGA exists, there's an option in some ATI/AMD drivers even)
Component 480p should work.

No idea if simple transistor combiner works.
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Gunstar
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Re: GBS 8200/8220 CFW Project

Post by Gunstar »

Jon Nielsen wrote:
Gunstar wrote:@NoAffinity - Same, got an 8220 without the decoupling mod and it's pretty solid. I think rama said it's his favourite model? PS I need to try out your wifi aerial mod!
Did you do anything else to make your 8220 solid? I have a 8220 board that wasn't put to use yet because the 8200 I found was so much better.
Just the recommended mods on the wiki (minus the ones for the charge pump).
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maxtherabbit
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Re: GBS 8200/8220 CFW Project

Post by maxtherabbit »

Hopefully we can get some better support for RGBHV at some point in the future :D
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Gunstar
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Re: GBS 8200/8220 CFW Project

Post by Gunstar »

Since my UMSA died I decided to build the Hackaday 'The ultimate VGA to SCART adapter' by Scart Vader. I messed up the pin out but finally got it working today. The cost to build it was probably around or a little less than the price of another UMSA from arcadeforge (I had to buy a PIC programmer and when I ordered the PCB, Corona had jacked up hobby prices). Probably cheaper to build now and even more so if you already have a PIC programmer. It can be powered alone from the pin 9 on a DE15 connector but I don't think the GBS does?
Image
It's designed to cut off the signal if it goes above 15khz, similar to the upcoming Tim Worthington adapter, which is great for outputing to a consumer CRT but that means it can't be used to pass RGBS 31khz to the GBS. Tim's adapter can dsiable this feature with a solder jumper I believe.
Image
Nice to be able to downscale my 360 games again!
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

https://www.ebay.com/itm/RGB-SCART-to-V ... 4648071271

Here's that frickin' guy again with the box using GBScontrol that gives zero recognition to Rama. Shame shame shame on this frickin' dood... bet he doesn't even have the clockgen in there :P
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