GBS 8200/8220 CFW Project

The place for all discussion on gaming hardware
strayan
Posts: 671
Joined: Sun Mar 19, 2017 8:33 pm

Re: GBS 8200/8220 CFW Project

Post by strayan »

rama wrote:Yeah, VGA with separate sync is hard to control or scale down.
Would it be easier to downscale RGBHV to 240p120? Would that even be possible?
Twin-X
Posts: 11
Joined: Tue Jul 22, 2008 12:15 pm

Re: GBS 8200/8220 CFW Project

Post by Twin-X »

West wrote:Hey Shmups and GBS Control users.

I've been looking for a 480i to 240p downscale solution for my Xbox360 and PS2 to connect to a Viletim 2.0 and then to Jamma on my 15khz Egret2.

Anyone try and run this type of setup in general? 480i Console to GBS for 240p downscaling then to 15khz Jamma?
Hi West,

I have an egret 2 and 3. To get the Xbox image running on a CRT or Arcade monitor you must use the HD component YBPR cable.
So connect the red blue and green to the GBS8200 Yellow is not needed. The image is perfect with this setup.

For me the real issue is i cannot find out how to connect the controllers to the cab :? If you have success with this please pm me the details.
I did a pad hack etc. nothing seems to work for me.
User avatar
West
Posts: 8
Joined: Sun Jun 29, 2014 4:17 am
Location: New York, NY

Re: GBS 8200/8220 CFW Project

Post by West »

Hey Twin-X, thanks for the info man. Cool to hear you've found success with this method. I was hoping that an Extron RGB or component cables might be solution to the problem and I'm glad to hear you've found success with it.

To connect the controllers to the cab, a padhack of some kind should work. I've built arcade sticks with padhacked XB360 pcbs and the principle is the same for connecting cab controls to it. But for my E2, I'm using a Viletim 2.0 with padhacked PS2 controllers which work perfectly (I use XB360 to PS2 converters for Xbox). If a padhack isn't working, you could always try one of the Brooks PCB's or an MC Cthulu depending on which consoles you want to connect:

https://focusattack.com/brook-universal ... h-headers/

https://paradisearcadeshop.com/home/ele ... by-toodles
rama
Posts: 1373
Joined: Wed Mar 08, 2017 3:15 pm

Re: GBS 8200/8220 CFW Project

Post by rama »

strayan:
No, I meant just what I wrote there: Combine H+V into CSync and you'll have a much better chance of it working.
That is because separate sync processing is difficult (read: probably not going to work as you want it to) because of an issue with the chip.
120Hz output is something I haven't looked into. It should be possible, but I have no idea whether it's worth doing.
User avatar
kitty666cats
Posts: 1270
Joined: Tue Nov 05, 2019 2:03 am
Location: Massachusetts, USA

Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

rama wrote:strayan:
No, I meant just what I wrote there: Combine H+V into CSync and you'll have a much better chance of it working.
That is because separate sync processing is difficult (read: probably not going to work as you want it to) because of an issue with the chip.
120Hz output is something I haven't looked into. It should be possible, but I have no idea whether it's worth doing.
It probably isn't, 240p @120Hz is usually quite pesky in regards to scrolling :(

Mike Chi found a pretty nice setting (in RetroArch) quite a while back to help alleviate said issue with 240p @ 120, but even then:
1. that's still just RetroArch
2. it's still not 100% resolved :'(

...that being said, worth a try with GBS CFW! This CFW is like Goku, it just gets moar and moar powerful and heroic and lovable :3
strayan
Posts: 671
Joined: Sun Mar 19, 2017 8:33 pm

Re: GBS 8200/8220 CFW Project

Post by strayan »

rama wrote:strayan:
No, I meant just what I wrote there: Combine H+V into CSync and you'll have a much better chance of it working.
That is because separate sync processing is difficult (read: probably not going to work as you want it to) because of an issue with the chip.
120Hz output is something I haven't looked into. It should be possible, but I have no idea whether it's worth doing.
Probably not worth doing because the only use case I was thinking of was for people using a PC CRT or CRT TV with RGBHV input. I know some monitors accept CSync on the 'HSync' input but I couldn't even begin to tell you how prevalent this was.

240p120 on a PC CRT looks remarkably PVM like though. GCVideo outputting 240p120 signal to a cheap DELL CRT: https://i.imgur.com/4IjsmD3.jpg
User avatar
Gollot
Posts: 14
Joined: Tue Apr 21, 2020 12:05 pm

Re: GBS 8200/8220 CFW Project

Post by Gollot »

Hello a little question, if i can pick beetween the Original GBS-8200 and the yellow button (2017) revision, which one should i buy? Or they are both equally as good?
User avatar
NoAffinity
Posts: 1018
Joined: Mon May 07, 2018 5:27 pm
Location: Escondido, CA, USA

Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

Avoid the yellow button versions.

Sent from my SM-G955U using Tapatalk
Ryoandr
Posts: 269
Joined: Mon Jun 12, 2017 4:12 am

Re: GBS 8200/8220 CFW Project

Post by Ryoandr »

Finally did some 15k downscale tests. Results are great !

https://imgur.com/a/DLwBXIi
User avatar
manuelink64
Posts: 11
Joined: Fri Jul 27, 2018 3:38 pm
Location: La Serena, Chile

Re: GBS 8200/8220 CFW Project

Post by manuelink64 »

rama wrote:So the luma signal (green plug) is too hot when it arrives at the scaler chip.
Check the resistors that are on the luma path (R18 and R29). One should be 75 Ohm, the other 200 Ohm.
Also look carefully for any damaged parts further along the luma line.
I've checked all and everything seems fine, the signals levels on the input pins are good.
but still I can't get work the Component input, probably is something wrong in the TV5725.(turns very hot) :(

I give up :cry:
captaineos
Posts: 28
Joined: Mon Aug 06, 2018 2:20 am

Re: GBS 8200/8220 CFW Project

Post by captaineos »

I've been so taken with this scaler that I'm now developing a kit for my local computer club. It's Apple II era focused and we all have Apple IIGS computers with no real affordable scaling option for the RGB out.

Personally I use mine for all gaming consoles and have ran out of preset banks.

Secondly I would like to define custom resolutions (based on standard timings such as a VESA 1024x768).

Could the CFW allow for more presets or resolutions?

I have tested the current draw as 0.45A to 0.55A at 5.01volts so a good quality 5V 1A rated USB power pack is more than ample for a CFW'd GBS8200.
User avatar
NoAffinity
Posts: 1018
Joined: Mon May 07, 2018 5:27 pm
Location: Escondido, CA, USA

Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

captaineos wrote:
I have tested the current draw as 0.45A to 0.55A at 5.01volts so a good quality 5V 1A rated USB power pack is more than ample for a CFW'd GBS8200.
Is that with the clock generator board added?

I dont expect it adds too much more to the load, but would be good to know what a complete setup with optional components would draw. Also, any additional load created when using gbs-8220 and both vga outputs simultaneously?

I go for a 2A min. 5v wall wart. Theyre cheap enough and always better to have it and not need it, when it comes to power. :)


Sent from my SM-G955U using Tapatalk
User avatar
Tempystral
Posts: 1
Joined: Mon May 11, 2020 5:40 pm
Contact:

Re: GBS 8200/8220 CFW Project

Post by Tempystral »

Hey folks - I've been really impressed with the videos I've seen of this scaler and have one on the way. I'm intending to use it in a Wii + eMac mod with the original CRT. Looking forward to updating you on the progress.

I am curious though, why is the stock GBS-series so mediocre? Obviously there are issues with the physical layout of the board, but was the original processor not fast enough or was firmware lacking or something? It's a little shocking how much of an improvement the custom firmware makes.

I'll report back with updates when I get my board in!
Ingy
Posts: 10
Joined: Sat May 20, 2017 12:19 pm

Re: GBS 8200/8220 CFW Project

Post by Ingy »

I've been having a go at building one of these and doing the various modifications (still waiting on the clock board), it's been a fun project, though kind of a comedy of errors with my soldering skills! The VGA and component inputs seem to be working fine now, but I'm having trouble getting a stable picture from the SCART input I added yesterday.

I assume it's a sync issue, I'm using a PCB with an LM1881 I ordered from Retro Gaming Cables (since it was cheaper than buying all the parts separately), and I'm trying to follow the circuit diagram in this post: viewtopic.php?f=6&t=55948&p=1153713#p1153713

I really don't know the first thing about building circuits, so I thought I'd better check that this actually has a chance of working the way I'm imagining it does:
Spoiler
Image
The blue resistor is 75 ohms 0.6W (not that I paid any attention to the wattage when I was ordering it) and the orange capacitor is 0.1uF 50V. The rocker switch has the 5V input of the GBS-8200 going to one prong, and I'm trying to power both the ESP8266 and the sync splitter from the other prong (no idea if this is stupid :)). I had the ground of the sync splitter going to the one next to SDA and SCL on the GBS-8200 at first, I've since tried moving it to connect to the ground point on the ESP8266 that's attached to the black wire of the GBS-8200's 5V input, which didn't help.

I ordered a multimeter a couple of weeks ago that would surely make it easier to figure things out, but it hasn't arrived yet, so I'd appreciate any guidance in the meantime!
hellbelly
Posts: 100
Joined: Sat Sep 20, 2008 6:24 pm
Location: UK
Contact:

Re: GBS 8200/8220 CFW Project

Post by hellbelly »

I thought the point of the board from RGC was it had all the required components on it to output correctly levelled csync, so are you sure you need the resistor and capacitor you’ve added?

Hey, interesting looking enclosure!
Ingy
Posts: 10
Joined: Sat May 20, 2017 12:19 pm

Re: GBS 8200/8220 CFW Project

Post by Ingy »

Yeah, it's this one! https://www.thingiverse.com/thing:3913273

I ordered it 3D-printed since it looked like it would work well for my purposes (and it does), unfortunately I managed to slightly warp that side by using a hair dryer on the heat-shrink tubing at the rocker switch. Seems obvious in hindsight that something 3D-printed wouldn't stand up to heat, but at least the lid still fits well enough for it to look tidy from the front. :)

On the RGC board I could only see the 470 ohm resistor on the output and the 100nF (I assume that's the value, it's not stated on their page) capacitor on the input, so I figured I'd still have to add the 75 ohm resistor to ground and the 100nF power bypass capacitor. Not sure if I'm doing it correctly though!
Ingy
Posts: 10
Joined: Sat May 20, 2017 12:19 pm

Re: GBS 8200/8220 CFW Project

Post by Ingy »

It was the power thing after all, I switched to getting power for the sync stripper from SCART pin 8 and it's all working fine now. I think that approach should be okay for the SCART cables I'm likely to use with it.

I'm finding that I have to power the VGA-to-HDMI adapter I bought through USB to get a picture, is that typical? I bought this one, it looked the most like another I saw recommended:

Image

It's manageable of course, just a bit of a pain.
herr-g
Posts: 3
Joined: Mon Aug 02, 2010 7:39 pm

Re: GBS 8200/8220 CFW Project

Post by herr-g »

Well, you can easily route the 5V from your PSU through VGA Pin9 to the internal regulator of the VGA dongle.
These are the pictures from my solution: https://circuit-board.de/forum/index.ph ... post828412
Ingy
Posts: 10
Joined: Sat May 20, 2017 12:19 pm

Re: GBS 8200/8220 CFW Project

Post by Ingy »

herr-g wrote:Well, you can easily route the 5V from your PSU through VGA Pin9 to the internal regulator of the VGA dongle.
These are the pictures from my solution: https://circuit-board.de/forum/index.ph ... post828412
Thanks a lot, that's working great! Weirdly, the VGA connector on my adapter is upside down relative to yours, but it was still easy enough to route the wire to the other side of the board.
rama
Posts: 1373
Joined: Wed Mar 08, 2017 3:15 pm

Re: GBS 8200/8220 CFW Project

Post by rama »

captaineos:
I don't want to add even more duplicated buttons to the UI, but that's the only reason for not having more preset save slots.
That part of the UI should be redesigned to reduce button redundancy.
My JS / CSS isn't the best though. I take offers :p

Tempystral:
Stock GBS and all the other cheap scalers out there have the required hardware for producing good images.
The issue with these is purely that the software doesn't even try to go for quality.
Instead, the software needed to be cheap and done quickly.
You get the expected results from that: The bare minimum.

I developed this with an image quality priority.
It took ages, but at least now everyone can have a cheap yet good scaler :)
User avatar
kitty666cats
Posts: 1270
Joined: Tue Nov 05, 2019 2:03 am
Location: Massachusetts, USA

Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

kitty666cats wrote:If I'm feeling like putzing around and displaying PlayStation 4 in 240p on a JVC TM-H150CG, would it (for some reason) be more ideal to run a 480i RGBS image via a scan converter into the GBS versus, say, 480p output via a Portta HDMI to VGA?
Okay, so I tested with and without, and my particular scan converter definitely helped a lot! Without it, trying to get stable image in 240p from the PS4 was super annoying and still had issues. My particular model is - https://www.analogway.com/files/uploads ... manual.pdf

but I'm sure any Extron VSC is fine. Also lul @ PS4 in 240p, I am a sick boy. It went fine, did some Dark Souls 1 PvP and PvE - latency was not an issue
Ingy
Posts: 10
Joined: Sat May 20, 2017 12:19 pm

Re: GBS 8200/8220 CFW Project

Post by Ingy »

I added the clock modification last night, so this is the current state of my board (please excuse all the burn marks :)): https://i.imgur.com/WQMdPS5.jpg

I've performed all the modifications in this image as well and checked them as best I can without a multimeter: viewtopic.php?p=1399682#p1399682

I'm still seeing some diagonal waves on the image at times, and I wondered if anyone might know a likely cause: https://i.imgur.com/Wd3zCgT.mp4

I thought it might be from the SCART connector so I added a bunch of ground wires, but I'm seeing it on the component input as well. I've also tried a couple of other 5V 1-2A power supplies that I had lying around with no change.
hellbelly
Posts: 100
Joined: Sat Sep 20, 2008 6:24 pm
Location: UK
Contact:

Re: GBS 8200/8220 CFW Project

Post by hellbelly »

Have you ruled out the VGA to HDMI adapter? Can you try just VGA?
Ingy
Posts: 10
Joined: Sat May 20, 2017 12:19 pm

Re: GBS 8200/8220 CFW Project

Post by Ingy »

I tried it just now and I'm seeing the same kind of pattern, though the waves seemed to have a slightly higher frequency. I'll try disconnecting the 5V that I have going to VGA pin 9 to make sure it's not that, but I'm pretty sure I was seeing it before I added that wire.

Edit: Still there with it disconnected.
Ingy
Posts: 10
Joined: Sat May 20, 2017 12:19 pm

Re: GBS 8200/8220 CFW Project

Post by Ingy »

I've noticed that the wave pattern seems to change when I use the "Cycle SDRAM clock speed" button in the Development section of the web interface. It almost seems to disappear for a little while at some of the settings (generally 129MHz and 144MHz) but it always recurs.
User avatar
kitty666cats
Posts: 1270
Joined: Tue Nov 05, 2019 2:03 am
Location: Massachusetts, USA

Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

Image

Image

Just a reminder that this is a dang fine way to connect your console SCART cables! :)
User avatar
_rm_
Posts: 331
Joined: Wed Sep 04, 2013 8:31 pm
Location: Portugal

Re: GBS 8200/8220 CFW Project

Post by _rm_ »

Sorry if this has been convered before:

Can you connect an Xbox 360 (official VGA) to the GBS8200?

I'm trying this on a friend's GBS with the custom firmware but i can't get no sync. Tested on Arcade monitor and PC monitor and both with no sync.

I must add that with an arcade PCB the GBS works great, so it's not a faulty unit.

Thank you all in advance
User avatar
Guspaz
Posts: 3136
Joined: Tue Oct 06, 2015 7:37 pm
Location: Montréal, Canada

Re: GBS 8200/8220 CFW Project

Post by Guspaz »

What are you trying to do with it exactly? 480i60 -> 240p120? That's the only thing I could think of that would be useful for that setup, since you can't display 240p60 on a PC CRT and the 360 already natively supports 480p60 and up over VGA.
User avatar
_rm_
Posts: 331
Joined: Wed Sep 04, 2013 8:31 pm
Location: Portugal

Re: GBS 8200/8220 CFW Project

Post by _rm_ »

Guspaz wrote:What are you trying to do with it exactly? 480i60 -> 240p120? That's the only thing I could think of that would be useful for that setup, since you can't display 240p60 on a PC CRT and the 360 already natively supports 480p60 and up over VGA.
Yup, downscale to 15khz.
User avatar
Gunstar
Posts: 617
Joined: Wed Apr 09, 2014 10:29 am
Location: UK

Re: GBS 8200/8220 CFW Project

Post by Gunstar »

_rm_ wrote:Sorry if this has been convered before:

Can you connect an Xbox 360 (official VGA) to the GBS8200?

I'm trying this on a friend's GBS with the custom firmware but i can't get no sync. Tested on Arcade monitor and PC monitor and both with no sync.

I must add that with an arcade PCB the GBS works great, so it's not a faulty unit.

Thank you all in advance
It might get support someday (with an H+V > csync mod of sorts?) but Rama said it doesn't have a mode detect unit and is difficult with the two separate syncs. Might be best to get the 360 YPbPr cables if they're available to you.

You can try moving the picture right a bit from the web UI to see if your set can get a stable picture (might help with sync?) but the picture will be offset to one side. I think you can you then use HS move left/right to bring it back in line but iirc it will still be cut off or show some part of the picture incorrectly.
Image
^360 VGA, the second pic is after nudging the picture right for it to become stable
Post Reply