GBS 8200/8220 CFW Project

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DogP
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Re: GBS 8200/8220 CFW Project

Post by DogP »

I can't say for sure, but probably not exactly a "bug", but related to where the input and output V-syncs occur relative to each other. 17ms is ~60 Hz, so for example if the output signal just drew the first line to the monitor, then the input signal gets the first line from the video source... the GBS will have to wait ~17ms before it gets a chance to draw the first line again.

Again, I haven't played with gbscontrol very much, but have you tried adjusting the FrameTime Lock and Switch Lock options? That talks about keeping the input and output timings aligned. Ideally, the output V-sync would track the input V-sync... but given the wide range of inputs/outputs supported, it wouldn't be surprising if they were somewhat independent (at least depending on the settings).

It's not surprising that unplugging/replugging the input signal doesn't change it, since that wouldn't change the input or output signal timing. But how about power cycling the input device while leaving the GBS running? If it was the GBS itself causing the lag, that wouldn't have any affect. If it's relative timing of the V-syncs, then the power cycled signal it should come up at a different random offset.

DogP
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Josh128
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Re: GBS 8200/8220 CFW Project

Post by Josh128 »

DogP wrote:I can't say for sure, but probably not exactly a "bug", but related to where the input and output V-syncs occur relative to each other. 17ms is ~60 Hz, so for example if the output signal just drew the first line to the monitor, then the input signal gets the first line from the video source... the GBS will have to wait ~17ms before it gets a chance to draw the first line again.

Again, I haven't played with gbscontrol very much, but have you tried adjusting the FrameTime Lock and Switch Lock options? That talks about keeping the input and output timings aligned. Ideally, the output V-sync would track the input V-sync... but given the wide range of inputs/outputs supported, it wouldn't be surprising if they were somewhat independent (at least depending on the settings).

It's not surprising that unplugging/replugging the input signal doesn't change it, since that wouldn't change the input or output signal timing. But how about power cycling the input device while leaving the GBS running? If it was the GBS itself causing the lag, that wouldn't have any affect. If it's relative timing of the V-syncs, then the power cycled signal it should come up at a different random offset.

DogP
Im not sure about power cycling the source, but very possibly-- I will need to re-test. Repeatedly pressing the same resolution button you currently are using does it as well, for sure. What you are saying makes sense, but what doesnt make sense is that the lag decreases by almost the same exact amount every time you hit the button, then when it gets as low as its going to go it resets to ~17ms then repeats the process of incrementally going lower each time you hit the button. My unit has the clockgen installed, so maybe that has something to do with it. Odd. Once its running, unless you power cycle, switch resolutions, or re-sync by hitting the same button, the lag stays the same and doesnt drift according to the TS. This may be why the GunCon wouldnt work with the GBS and the VGA monitor when I was testing. Perhaps if I hit the res button enough, when it got to sub 2ms of lag it would have started working.
DogP
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Re: GBS 8200/8220 CFW Project

Post by DogP »

Josh128 wrote:what doesnt make sense is that the lag decreases by almost the same exact amount every time you hit the button, then when it gets as low as its going to go it resets to ~17ms then repeats the process of incrementally going lower each time you hit the button.
Again, just making an educated guess... but I'd suggest that hitting the button causes the unit to reconfigure the output, which takes a small amount of time to do (e.g. it typically does "draw line 1, draw line 2, draw line 3", but pressing the button causes it to do "draw line 1, wait for reconfigure, draw line 2, draw line 3").

In that waiting time, the output "slips" in time vs. the input, and therefore the input "catches up" to the output (input V-sync getting closer to the output V-sync). If you do it too much, the input goes past the output, which again makes the unit almost an entire frame (17ms) behind.

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Josh128
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Re: GBS 8200/8220 CFW Project

Post by Josh128 »

That could explain it man. It'll probably never happen and may not even be possible, but if the unit could detect the start of a scan and wait to sync at that point it could always be a sub 1ms lag unit. In any case, for $32 or so its still the best bang for your buck out there.
DogP
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Re: GBS 8200/8220 CFW Project

Post by DogP »

If you haven't already, definitely give the Active FrameTime Lock options a try. I assume that corresponds to what the programming manual refers to as "Sync Lock Mode" or "Frame Lock Mode". It sounds like sync lock mode synchronizes to horizontal and vertical sync, while frame lock mode locks to just the vertical sync.

The manual recommends "Free Run Mode", to "avoid destroy the TV" (some TVs/monitors can't handle and can be damaged by frequencies outside their usable range). It describes that as "output timing have no relation with input timing", so if it's in that mode, I think it'd operate like I was describing.

DogP
fernan1234
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Re: GBS 8200/8220 CFW Project

Post by fernan1234 »

DogP wrote:If you haven't already, definitely give the Active FrameTime Lock options a try. I assume that corresponds to what the programming manual refers to as "Sync Lock Mode" or "Frame Lock Mode". It sounds like sync lock mode synchronizes to horizontal and vertical sync, while frame lock mode locks to just the vertical sync.
I believe those settings are disabled/bypassed when the clockgen mod is added.
USSCrazybat
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Re: GBS 8200/8220 CFW Project

Post by USSCrazybat »

Currently running a base GBS-C (no clockgen, only hardware mod is removed C11) and it's working well in my jamma cab. However, when I test CPS2 boards on it the brighter colors are too intense. I've tried all gain options but can't get the colors dark enough. Have also tinkered with monitor settings to no luck. Would the 100 ohms resistor on the RGBS input possibly solve the problem?
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

Gbs-c is optimized for consoles. I always get an overly bright image with any 15khz arcade source. Setting to minimum gain makes it almost right, but still just a bit overly bright.

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arm1
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Re: GBS 8200/8220 CFW Project

Post by arm1 »

Does anybody know how to solve this ? I bought this board but it is not giving an video image

Classic XBOX w/ component cable

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Chipnetics
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Re: GBS 8200/8220 CFW Project

Post by Chipnetics »

Hi all, just wanted to drop a note I've added a variant of the GBSC with SCART input (which I've dubbed the 'GBSC Apogee'). Maybe some of you will find it useful.

- Rear facing SCART input, so all your cabling can be at the rear of unit.
- Recessed VGA to HDMI output, with integrated power.[*1]
- Texas Instruments LM1881 sync separator and cleaner.[*2]
- 3.5mm audio output (which can feed into the HDMI adapter for audio injection).
- Only an inch larger than the GBS8200 footprint, with no side-ports.

[*1] Note that on the VGA to HDMI adapter, the USB power is not used, and instead the adapter is modified to take power from the DSUB header. This is a lovely modification in that it avoids having to run a USB cable to the dongle.

[*2] This unit strips csync from composite video (from SCART input).

The DSUB at the rear of the unit can still be used (located underneath the SCART port) with basic VGA cables that do not have a large housing. The traditional blue-ended VGA cables common throughout the 90’s will fit fine.

TRIAD PSU, Clockgen, and VGA to HDMI included as standard.

Purchase link: https://www.tindie.com/products/chipnet ... converter/
Website article: https://chipnetics.com/projects/hw/gbsc_apogee/

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Image
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Shelcoof
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Re: GBS 8200/8220 CFW Project

Post by Shelcoof »

Chipnetics wrote:Hi all, just wanted to drop a note I've added a variant of the GBSC with SCART input (which I've dubbed the 'GBSC Apogee'). Maybe some of you will find it useful.

- Rear facing SCART input, so all your cabling can be at the rear of unit.
- Recessed VGA to HDMI output, with integrated power.[*1]
- Texas Instruments LM1881 sync separator and cleaner.[*2]
- 3.5mm audio output (which can feed into the HDMI adapter for audio injection).
- Only an inch larger than the GBS8200 footprint, with no side-ports.

[*1] Note that on the VGA to HDMI adapter, the USB power is not used, and instead the adapter is modified to take power from the DSUB header. This is a lovely modification in that it avoids having to run a USB cable to the dongle.

[*2] This unit strips csync from composite video (from SCART input).

The DSUB at the rear of the unit can still be used (located underneath the SCART port) with basic VGA cables that do not have a large housing. The traditional blue-ended VGA cables common throughout the 90’s will fit fine.

TRIAD PSU, Clockgen, and VGA to HDMI included as standard.

Purchase link: https://www.tindie.com/products/chipnet ... converter/
Website article: https://chipnetics.com/projects/hw/gbsc_apogee/

Image

Image

Nice your based in Canada
Been looking for a cheap downscaling solution

May just pick one up :wink:
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Chipnetics
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Re: GBS 8200/8220 CFW Project

Post by Chipnetics »

Regarding the GBSC Apogee above with SCART input; I have one 'prototype' unit that I've man-handled through debugging and has no clock-gen mod (broke pins off), but works fine otherwise. Has one small bodge wire. I'd be willing to let it go for $90 shipped w/ tracking if any takers. Will include triad PSU. Drop PM if interested.
fernan1234
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Re: GBS 8200/8220 CFW Project

Post by fernan1234 »

Chipnetics makes great units. I still have one from before the re-designed PCB was added. Pair one with an OSSC and it really feels like a next-gen scaler solution, unfortunately only held back by the GBS board's inherent issue with bleeding on some colors like blue and red, which is only an issue when using scanlines, but they are a must for me.

If there were a way to fix that, I probably wouldn't need to even consider any of the current or upcoming scalers.
USSCrazybat
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Re: GBS 8200/8220 CFW Project

Post by USSCrazybat »

NoAffinity wrote:Gbs-c is optimized for consoles. I always get an overly bright image with any 15khz arcade source. Setting to minimum gain makes it almost right, but still just a bit overly bright.

Sent from my SM-G955U using Tapatalk
Was able to counteract this by keeping the RGB pots on in my second build. Has been running for a few hours now without issue with colors or fading into green/blue.

Have noticed quite a bit of screen tearing/flickering. Is clock gen essential for this?
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

USSCrazybat wrote:Have noticed quite a bit of screen tearing/flickering. Is clock gen essential for this?
Clockgen will almost certainly alleviate that problem, I am 99% sure. I guess some people have units that seem to be fine without clockgen, but it seems to be a crapshoot which units/video chains need it or not…
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Gunstar
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Re: GBS 8200/8220 CFW Project

Post by Gunstar »

Voultar GBS build video:
Image

The vertical mount of the ESP board is really interesting as was his choice to solder a permanent 100ohm resistor to the underside between ground and sync. I think I might do the vertical mount whilst I find time to put the GBS in a proper case.
USSCrazybat
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Re: GBS 8200/8220 CFW Project

Post by USSCrazybat »

kitty666cats wrote:
USSCrazybat wrote:Have noticed quite a bit of screen tearing/flickering. Is clock gen essential for this?
Clockgen will almost certainly alleviate that problem, I am 99% sure. I guess some people have units that seem to be fine without clockgen, but it seems to be a crapshoot which units/video chains need it or not…
So I installed the clock gen on two different units. Probably the most precise soldering I've ever had to do, but I'm pretty pleased with it. Unfortunately...it didn't fix the jittering/tearing.

But you know what did? The goddamn 100ohm resistor on sync/ground, which I'd tossed away when it didn't fix my color problems.

In short, for PCBs or at least CPS2 if you're plugging the JAMMA harness directly into the GBS, keep your RGB pots, put on your RGBS 100ohm resistor. Not sure if clock gen is necessary but it can't hurt in the long run.
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

USSCrazybat wrote:
kitty666cats wrote:
USSCrazybat wrote:Have noticed quite a bit of screen tearing/flickering. Is clock gen essential for this?
Clockgen will almost certainly alleviate that problem, I am 99% sure. I guess some people have units that seem to be fine without clockgen, but it seems to be a crapshoot which units/video chains need it or not…
So I installed the clock gen on two different units. Probably the most precise soldering I've ever had to do, but I'm pretty pleased with it. Unfortunately...it didn't fix the jittering/tearing.

But you know what did? The goddamn 100ohm resistor on sync/ground, which I'd tossed away when it didn't fix my color problems.

In short, for PCBs or at least CPS2 if you're plugging the JAMMA harness directly into the GBS, keep your RGB pots, put on your RGBS 100ohm resistor. Not sure if clock gen is necessary but it can't hurt in the long run.
Ahhhh, I always forget about that resistor - I input RGBS and not RGBHV 100% of the time so it's just gonna be on there forever, haha
TimbleThimble
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Re: GBS 8200/8220 CFW Project

Post by TimbleThimble »

Hey guys, is anyone having any issues running PAL 1080p50 with clockgen or is it just me?

I've reported a similar problem I've had regarding 1080p not working at the same time as the 50-60hz toggle on the GitHub because I figured that one was more of an actual bug then potentially what I'm experiencing here. But even then the 1080p50 mode still doesn't seem to work correctly for me; my board has a clock-gen and does work correctly in all other modes.

Least for me 1080p50 is far off to the right, no amount of adjusting I can do really fixes it. I can centre it but I can't scale it down horizontally because apparently it's already at the limit. I would just use the other PAL modes but my main TV doesn't like those modes and just having the option would help a lot with streamlining my setup.

Essentially just wondering if anyone has any work arounds, would be greatly appreciated!

Examples:
https://i.imgur.com/K55BnVG.png
https://i.imgur.com/pIFbxS0.png
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kitty666cats
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Re: GBS 8200/8220 CFW Project

Post by kitty666cats »

TimbleThimble wrote:Hey guys, is anyone having any issues running PAL 1080p50 with clockgen or is it just me?

I've reported a similar problem I've had regarding 1080p not working at the same time as the 50-60hz toggle on the GitHub because I figured that one was more of an actual bug then potentially what I'm experiencing here. But even then the 1080p50 mode still doesn't seem to work correctly for me; my board has a clock-gen and does work correctly in all other modes.

Least for me 1080p50 is far off to the right, no amount of adjusting I can do really fixes it. I can centre it but I can't scale it down horizontally because apparently it's already at the limit. I would just use the other PAL modes but my main TV doesn't like those modes and just having the option would help a lot with streamlining my setup.

Essentially just wondering if anyone has any work arounds, would be greatly appreciated!

Examples:
https://i.imgur.com/K55BnVG.png
https://i.imgur.com/pIFbxS0.png
Have you messed with the H and V adjustments under 'System'? If not, try adjusting that a bit while switching back and forth between that and the standard H & V size/position & border masking whenever things start to look weird/distorted.
TimbleThimble
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Re: GBS 8200/8220 CFW Project

Post by TimbleThimble »

kitty666cats wrote:
TimbleThimble wrote:Hey guys, is anyone having any issues running PAL 1080p50 with clockgen or is it just me?

I've reported a similar problem I've had regarding 1080p not working at the same time as the 50-60hz toggle on the GitHub because I figured that one was more of an actual bug then potentially what I'm experiencing here. But even then the 1080p50 mode still doesn't seem to work correctly for me; my board has a clock-gen and does work correctly in all other modes.

Least for me 1080p50 is far off to the right, no amount of adjusting I can do really fixes it. I can centre it but I can't scale it down horizontally because apparently it's already at the limit. I would just use the other PAL modes but my main TV doesn't like those modes and just having the option would help a lot with streamlining my setup.

Essentially just wondering if anyone has any work arounds, would be greatly appreciated!

Examples:
https://i.imgur.com/K55BnVG.png
https://i.imgur.com/pIFbxS0.png
Have you messed with the H and V adjustments under 'System'? If not, try adjusting that a bit while switching back and forth between that and the standard H & V size/position & border masking whenever things start to look weird/distorted.
I can only scale V, H won't let me go any smaller cause it prints out that it's already at it's limit. I can sort've centre the image and mess with border masking but the further I go the more the scaler starts to glitch out.
M-Reimer
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Re: GBS 8200/8220 CFW Project

Post by M-Reimer »

Is there a Atmega based scaler firmware which is still maintained?

I would prefer to not have Wifi or a webinterface on a scaler. All I want to use are the SNES and N64 and I don't want to configure a scaler all the time. Best case my two consoles "just work". So no need to have such a device on my Wifi all the time.
stj
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Re: GBS 8200/8220 CFW Project

Post by stj »

hello people.

i am building one of these and have a few questions i cant find answers for.

1: do the 4 buttons still do anything after the esp is used?
2: does the MTV230 chip still serve any function or can i remove it?
3: is the eeprom still being used, or can i remove it?

reason for the questions,
if i remove the buttons it creates a perfect size area to mount my esp! :P
if i remove the MTV230 it creates a good space for the OLED :mrgreen:

obviously if i do this i will post back pictures.
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

The buttons can be removed. That is where I mount esp's. Not sure about the rest.

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stj
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Re: GBS 8200/8220 CFW Project

Post by stj »

thanks.

unfortunatly i'm going to have to re-think my design.
i ran the gbs for about 16hours and the scaler gets pretty hot - so the heatsink is there for a reason.
so i wont be putting the clock-gen board on it like other people do.

this has lead me to the idea of mounting the clockgen and the esp on the underside and just putting the oled on top.
that in turn means i dont need to remove anything.

i have not got the clockgen from china yet though - so nothing is decided, BUT i am not going to obstruct that heatsink!!
i may even see if i have any tiny fans in my parts box from old laptops!
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

Esp on the underside=unreliable wifi

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Odolwa
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Re: GBS 8200/8220 CFW Project

Post by Odolwa »

When it comes to handling interlaced content, which is better, the Retrotink 5X Pro or the GBS-8200? Also, when it comes to handling progressive content, which is better, the OSSC or the GBS-8200?
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Odolwa
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Re: GBS 8200/8220 CFW Project

Post by Odolwa »

Shelcoof wrote:
Chipnetics wrote:Hi all, just wanted to drop a note I've added a variant of the GBSC with SCART input (which I've dubbed the 'GBSC Apogee'). Maybe some of you will find it useful.

- Rear facing SCART input, so all your cabling can be at the rear of unit.
- Recessed VGA to HDMI output, with integrated power.[*1]
- Texas Instruments LM1881 sync separator and cleaner.[*2]
- 3.5mm audio output (which can feed into the HDMI adapter for audio injection).
- Only an inch larger than the GBS8200 footprint, with no side-ports.

[*1] Note that on the VGA to HDMI adapter, the USB power is not used, and instead the adapter is modified to take power from the DSUB header. This is a lovely modification in that it avoids having to run a USB cable to the dongle.

[*2] This unit strips csync from composite video (from SCART input).

The DSUB at the rear of the unit can still be used (located underneath the SCART port) with basic VGA cables that do not have a large housing. The traditional blue-ended VGA cables common throughout the 90’s will fit fine.

TRIAD PSU, Clockgen, and VGA to HDMI included as standard.

Purchase link: https://www.tindie.com/products/chipnet ... converter/
Website article: https://chipnetics.com/projects/hw/gbsc_apogee/

Image

Image

Nice your based in Canada
Been looking for a cheap downscaling solution

May just pick one up :wink:
I'd like to see a YouTube video of this.
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NoAffinity
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Re: GBS 8200/8220 CFW Project

Post by NoAffinity »

Odolwa wrote:When it comes to handling interlaced content, which is better, the Retrotink 5X Pro or the GBS-8200? Also, when it comes to handling progressive content, which is better, the OSSC or the GBS-8200?
Cant speak to the retrotink cuz I dont own one, but the fast deinterlacing of the gbs is very good.

The ossc vs gbs comparison is subjective and reliant on your definition of "better". For pixel perfection with optimized profiles, the ossc produces a crisper image. Ossc generic profiles vs gbs, i would argue that gbs has a slight edge. Gbs handling of mode switching plus very good scaling at extremely low lag truly is a great solution for certain use cases.

Just one man's opinions.

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Josh128
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Re: GBS 8200/8220 CFW Project

Post by Josh128 »

I find the Tink5X and the GBS-Cs deinterlacing very similiar. Im not sure if the GBS-Cs deinterlacing adds lag or not, but the 5X definitely does not. Both can also replicate CRT 480i look very well with GBS-C's "Bob+scanlines" and 5X's "CRT Simulate".

If you are feeding an analog / CRT monitor, the GBS-C is the way to go for 99% of what you need-- but if you want some GunCon 2 action on a 31KHz or higher CRT or if you are feeding a digital panel, 5X all the way.
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