240p via HDMI on Raspberry Pi to RGBS, no need for RGB hats!

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vol.2
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by vol.2 »

setiawan wrote: I've been able to pass through the equivalent resolution with pixel doubling, but it comes out weird. Like there are gaps between each doubled pixel. Not sure what's up with that. It's otherwise a stable image:
At this point, it's just guessing, but what that looks like to me is that the pixel clock is too slow and/or the H and V blanking periods are too short. When you send the pixel-doubled modline, you are literally sending the pixels twice, but they should be sent so fast that you can't see both of them; you could think of it like the pixels are only half-width and the two pixels are taking up the space of one pixel. (that's not quite accurate, but it might help you to visualize what's going on).
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by setiawan »

vol.2 wrote:
setiawan wrote: I've been able to pass through the equivalent resolution with pixel doubling, but it comes out weird. Like there are gaps between each doubled pixel. Not sure what's up with that. It's otherwise a stable image:
At this point, it's just guessing, but what that looks like to me is that the pixel clock is too slow and/or the H and V blanking periods are too short. When you send the pixel-doubled modline, you are literally sending the pixels twice, but they should be sent so fast that you can't see both of them; you could think of it like the pixels are only half-width and the two pixels are taking up the space of one pixel. (that's not quite accurate, but it might help you to visualize what's going on).

Have tried a variety of hdmi_timings now, and nothing seems to fix the issue. I'll try it out on a LCD display at some point, without any converters, to see if that same issue is there. If so I'll raise it in the Raspberry Pi forums.

As for not being able to pass through 320x240p without pixel doubling, I'm starting to think it's down to the Portta converter. I tried passing HDMI signals from my PC (Nvidia GTX1060) using Nvidia's custom resolutions through the Portta, and peculiarly I can pass more or less the same resolutions that I can pass with the pi (e.g. the weird 640x480i resolution I'd been using, 640x240p works too), but 320x240p also doesn't work. Similarly with both pi and PC, whenever I try to pass 320x240p through the Portta, it doesn't 'sound' like the CRT is trying to display anything. I.e. the frequency of the CRT whine when trying to display 320x240p is the same as the frequency when it's trying to display an unconnected source.
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kitty666cats
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by kitty666cats »

For those who just rock 640x480 on a PC CRT, what are your favorite shaders? I use a mini-SLG when I go that particular route

https://www.instagram.com/p/CK77T8fFg3r ... 2l4f10ksg0

https://paradisearcadeshop.com/products ... 64c1&_ss=r

Very good option for laziness imho ;)
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Fudoh »

I use a mini-SLG when I go that particular route
won't replace using a shader though, if you want to completely eliminate any shimmering.
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kitty666cats
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by kitty666cats »

Fudoh wrote:
I use a mini-SLG when I go that particular route
won't replace using a shader though, if you want to completely eliminate any shimmering.
Ooh, that’s interesting! I really gotta study up on shaders beyond the “stock” ones that come with RetroArch / official Pi 3 images... I don’t even know where to find ‘em / which are the most highly-regarded! Most of the people in the Discords/forums I hang out in primarily use PC RetroArch or Wii. Looks like I have an afternoon project lined up for myself now :)
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by fernan1234 »

kitty666cats wrote:Ooh, that’s interesting! I really gotta study up on shaders beyond the “stock” ones that come with RetroArch / official Pi 3 images... I don’t even know where to find ‘em / which are the most highly-regarded! Most of the people in the Discords/forums I hang out in primarily use PC RetroArch or Wii. Looks like I have an afternoon project lined up for myself now
Before you spend too much time on this, keep in mind that the more "advanced" shaders won't work on a Pi. Well, I don't have experience with a Pi4 so that may be a bit different.

Even old Pi's support the "interlace" shader. I think you have to dig around for it in the shader subfolders though (it's not a standalone preset in the CRT folder, but rather a shader used by other standalone presets), and then you can save it as a custom preset for easier use. I highlight this one because it is very simple and does exactly what a SLG is supposed to do via software.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by kitty666cats »

fernan1234 wrote:
kitty666cats wrote:Ooh, that’s interesting! I really gotta study up on shaders beyond the “stock” ones that come with RetroArch / official Pi 3 images... I don’t even know where to find ‘em / which are the most highly-regarded! Most of the people in the Discords/forums I hang out in primarily use PC RetroArch or Wii. Looks like I have an afternoon project lined up for myself now
Before you spend too much time on this, keep in mind that the more "advanced" shaders won't work on a Pi. Well, I don't have experience with a Pi4 so that may be a bit different.

Even old Pi's support the "interlace" shader. I think you have to dig around for it in the shader subfolders though (it's not a standalone preset in the CRT folder, but rather a shader used by other standalone presets), and then you can save it as a custom preset for easier use. I highlight this one because it is very simple and does exactly what a SLG is supposed to do via software.
Thanks for the heads-up, I will give that one a try!
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by kitty666cats »

vol.2 wrote:
kitty666cats wrote:I wish I had picture perfect integer scaling fully worked out, but as you can see in the images it’s not quite there - I’m not too bothered as things look pretty good and there’s no scrolling distortion, but the OCD never fails to get me... :(

I swear that this whole mess is 1000% easier if you just use RetroArch instead of messing with Retropie. RA let's you lock integer scaling from the video settings menu and all of your settings are controlled in one place. (outside of the config.txt)

It's really not that big of a deal to compile. I'll try to make separate post giving a blow-by-blow here at some point.
Would love to be “shown the ropes” on how to do this if you find the time soon - I know my way around RetroArch quite well now, but I am not at all familiar with Linux / reconfiguring my whole entire Pi and starting back at square one :o
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vol.2
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by vol.2 »

kitty666cats wrote: Would love to be “shown the ropes” on how to do this if you find the time soon - I know my way around RetroArch quite well now, but I am not at all familiar with Linux / reconfiguring my whole entire Pi and starting back at square one :o
Ok. I will refer you first to the guides that make sense. Although the one caveat is that none of them are written with 15kHz CRTs in mind, so there are going to be some changes.

This is the best guide so far: https://gist.github.com/AlexMax/32e5d03 ... ea75736805

To get it running for a CRT, follow the advice of Alphanu1 in the middle of the comments. Some of this is a little out of date, especially the Core, I think probably there should be a configure line that includes one or more of the following added: -march=armv8-a+crc+simd -mcpu=cortex-a72 -mtune=cortex-a72. I believe that "march" overrides "mcpu," but I can't remember exactly.
There are many libraries missing in Buster. These need to be installed. The following is pretty much everything RA needs.

sudo apt install build-essential libxkbcommon-dev zlib1g-dev libfreetype6-dev libegl1-mesa-dev libgles2-mesa-dev libgbm-dev libavcodec-dev libsdl2-dev libsdl-image1.2-dev libxml2-dev yasm libavformat-dev libavdevice-dev libswresample-dev libavresample-dev libswscale-dev libv4l-dev libgl*-mesa-dev


Configure as follows.

CFLAGS="-mfpu=neon" ./configure --enable-alsa --enable-udev --enable-neon --disable-videocore --disable-opengl1 --disable-x11

Them make.

This method requires fkms-v3d to be enabled in the boot config.txt

This guy says he got everything square with GLES3, which is better because there are more cores compiled with ES support than there are for GL1 or GL2. Notably, I haven't found a compiled Mupen core for GL on Armhf. I'm sure it would work if you just compiled it (the mupen core) yourself for GL, but I haven't gotten around to it yet. There seems to be an available armhf for GLES binary available in one of the repository sites.

https://www.reddit.com/r/RetroArch/comm ... pberry_pi/

So I was going to next try that guy's guide because he claims amazing performance and stuff. Seems legit, but I just haven't had time recently.

IAC, I would also recommend you get a fresh SD card and hold onto your old one to fall back on if it things don't work out for you.

If you want to give this a shot, great, please share you results. If you want to wait for me to get caught up with it and fill you in, it may be a few weeks before I have the time.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by sedavenp »

vol.2 wrote:
Fudoh wrote:Both VGA to Scart adapters (from Retro Upgrades in the UK and from Arcadeforge in Germany) work perfectly.

One small tiny detail I can't work out though: when I set my Pi to boot in 480i (hdmi mode 6), Emulationstation assumes a 16:9 ratio, so everything looks a bit horizontally squeezed on a 4:3 screen. On a XGA display with the Pi set to output XGA as well, ES properly assumes a 4:3 display and displays accordingly.

Any idea how I can get ES to honor the 4:3 ratio during 480i output ?

I had a problem with my pi in the past where I couldn't get it to output in 4:3. I'm not sure if it's the same as yours though.

The first thing to check (assuming you haven't) is if you can get a 4:3 image when using a progressive mode. If you can, then your problem is not the same as mine, and it's most likely something specific to ES and I wouldn't be able to help.

If progressive modes also appear as squished 16:9, then it might be a firmware issue. That's exactly the reason that I stopped using the pi with a HDMI-VGA adapter so long ago. If you can't get progressive modes to work correctly, you can read below to troubleshoot, otherwise just ignore it.
Spoiler
There should be a call in the config.txt that expresses which blob to use for controlling the DRM/KMS graphics rendering pipeline. I don't have a Pi3, so I'm not sure if they ever figured out how to enable real KMS for that, when I was using one, it was FKMS or Legacy still.

Legacy is the Broadcom driver that they provided to run the GPU on the VC4. FKMS is a proprietary blob that the Pi foundation developed with the aid of Broadcom under strict NDA as a stop-gap measure for tailoring the VC4 to the Pi's particular breed of hardware and software. Only thing is that it took almost 10 years to get over the gap. Recently (end of last year) they finally got the VC6 on the Pi4 (and possibly the VC4 on the Pi3) to play nice with plain old regular KMS from the Linux kernel.

That was the issue that I ran into with the aspect ratio way back when.

Basically, I had to switch around dtoverlay=vc4-fkms-v3d. Try to find that in your config.txt. If it's there, comment it out and try again. If it's not, try to add it. If there is some other entry that calls "regular" KMS (it will not have a "k"), you can't use both switches. It will use whichever of them is last in the config.

There was another time that I had some overclocking issues that screwed it up. You can also try disabling all overclocking as a troubleshooting step.

None of this should be relevant if you have a correct aspect ratio on progressive resolutions.
Hi, I am trying to display RGBS from a Raspberry Pi 4 using portta hdmi to vga -> Extron 192 sync combiner -> sony pvm. I am having this same issue of getting an image that is kind of "squished" vertically so that it looks like a small 16:9 bar in the middle of the screen rather than 4:3. I have tried messing with the config in various ways and read through this whole thread. Has anyone found a workaround for this issue or am I better off ordering a retrotink ultimate from castlemania? Here is a photo of the image I am getting. Thanks for any help you guys can give me.
Image
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Fudoh
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Fudoh »

The problem is that there's no real solution to fix both the GUI (emulationstation) as well as the ingame graphics using the same method. That's why for any non-GPIO solution I recommend to run the front end at 480i instead.

For the emulators you simply set the aspect to custom (that's universal for alle emulators) and then you define a custom viewport in retroarch.cfg. It's better to do this seperately for all emus, since this allows you to use integer scaling for emus that have 300+ horizontal res and don't use multiple resolutions. If you don't use integer scaling you have to apply a simple bilinear filter to get rid of the scrolling artefacts. You won't notice it once running on a CRT.

Code: Select all

custom_viewport_width = "660" **
custom_viewport_x = "32"
custom_viewport_height = "224"
custom_viewport_y = "8"
** for integer scaling you can reduce this, e.g. to 640 (2x320), but it also means and the horizontal fill ratio is reduced a little bit.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by fernan1234 »

IMO you're better off just getting an old RBP3B+ to make things much simpler.

Also IMO bilinear filter is definitely noticeable on a CRT (maybe not a blurry old consumer TV) and should be left off always. Integer scaling (or a super resolution) is always the way to go.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by sedavenp »

Fudoh wrote:The problem is that there's no real solution to fix both the GUI (emulationstation) as well as the ingame graphics using the same method. That's why for any non-GPIO solution I recommend to run the front end at 480i instead.

For the emulators you simply set the aspect to custom (that's universal for alle emulators) and then you define a custom viewport in retroarch.cfg. It's better to do this seperately for all emus, since this allows you to use integer scaling for emus that have 300+ horizontal res and don't use multiple resolutions. If you don't use integer scaling you have to apply a simple bilinear filter to get rid of the scrolling artefacts. You won't notice it once running on a CRT.

Code: Select all

custom_viewport_width = "660" **
custom_viewport_x = "32"
custom_viewport_height = "224"
custom_viewport_y = "8"
** for integer scaling you can reduce this, e.g. to 640 (2x320), but it also means and the horizontal fill ratio is reduced a little bit.
For some reason, even when I try to adjust the aspect ratio in retroarch it won't expand beyond a certain height in the Y-directon. It seems like the picture is limited to a certain width and will not strech vertically to fit the screen. Here is an image of what it looks like. If i try to expand it further the image just gets cut off.

https://imgur.com/a/tlX6Ggc

The only thing that displays in 4:3 is the raspberry pi boot screen. Everything else, the front end and the emulators, display this weird squished image. Here is what i currently have in my config.txt

Code: Select all

hdmi_ignore_edid=0xa5000080
hdmi_pixel_encoding=2
avoid_safe_mode=1
disable_overscan=0
config_hdmi_boost=4
hdmi_drive=2
hdmi_group=1
hdmi_mode=8
kernel=zImage
hdmi_force_hotplug=1
gpu_mem_256=128
gpu_mem_512=256
gpu_mem_1024=512
dtparam=audio=on
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by sedavenp »

fernan1234 wrote:IMO you're better off just getting an old RBP3B+ to make things much simpler.

Also IMO bilinear filter is definitely noticeable on a CRT (maybe not a blurry old consumer TV) and should be left off always. Integer scaling (or a super resolution) is always the way to go.
This is good advice I hadn't thought of that. Definitely a cheaper option than the retrotink.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Fudoh »

Also IMO bilinear filter is definitely noticeable on a CRT (maybe not a blurry old consumer TV) and should be left off always. Integer scaling (or a super resolution) is always the way to go.
you have to pick the right shader of course (and I don't mean the default smoothing filter). But when super resolutions are no option (when running a HDMI to analogue converter solution), then it's a must, otherwise the horizontal scrolling will shimmering like hell.

As fernan1234 suggested the result you're seeing is likely a result of the Pi4's missing ability to handle 240p properly.

LOVELY Sony TV by the way!
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by fernan1234 »

Fudoh wrote:But when super resolutions are no option (when running a HDMI to analogue converter solution)
Super resolutions do with with a Pi 3 and HDMI to analogue solution, you just have to set the video config file like I originally posted before editing the OP. It can just lead to some issues with some emulators/cores, which is why I stopped suggesting it, but it does work and without issues perhaps for the majority of emulators.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by sedavenp »

Thanks to both of you for your feedback, really appreciate it. Looks like I'll go for either a 3B+ or the retrotink.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Fudoh »

Super resolutions do with with a Pi 3 and HDMI to analogue solution, you just have to set the video config file like I originally posted before editing the OP. It can just lead to some issues with some emulators/cores, which is why I stopped suggesting it, but it does work and without issues perhaps for the majority of emulators.
I didn't have much luck with it. Still you shouldn't dismiss any easy solutions. You can believe me, when I say, that I expect pretty good PQ from a setup like this and running on a 20" BVM the filtering does hardly hurt the quality. I'm not saying that super resolutions aren't superior, but it's a much more complicated setup and you still need the DAC to play along.

My main problem when trying it was the Pi drifts relatively far off the specified refresh rate causing more damage to smooth scrolling than the PQ would benefit from the sharpness boost.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Guile »

Is 240p not working well for the pi4? I ordered an hdmi to yuv converter to test. I looked into this months ago but saw some comments saying it didn't work without issues.

I saw a few different suggested configs, can anyone confirm one that works decently for 240p hdmi output on a pi4?

I also have a pi zero but that would really limit what systems I could emulate.

Has anyone tried getting 240p out of a firestick or an old laptop? Maybe I can try CRU and see if that works.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by vol.2 »

Guile wrote:Is 240p not working well for the pi4? I ordered an hdmi to yuv converter to test. I looked into this months ago but saw some comments saying it didn't work without issues.

I saw a few different suggested configs, can anyone confirm one that works decently for 240p hdmi output on a pi4?

I also have a pi zero but that would really limit what systems I could emulate.

Has anyone tried getting 240p out of a firestick or an old laptop? Maybe I can try CRU and see if that works.
I tried CEA mode 8 last year running Raspberry Pi OS with a self-compiled Retroarch binary and it worked fine on a RPi4 with a Portta HDMI-VGA adapter. No one can tell you what your results will be unless they have tested with your specific adapter. You can think of the adapter as being the final gate-keeper in you signal output because it's controller is going to have to interpret the output of the Pi. When those things are designed, they don't necessarily test them with every single possible output under the sun. They are going to cover the most frequent use-case scenarios.

Also, I'm not much one for RetroPie, so if you are using that, someone else might have to comment.

Running CRU on a laptop is out of scope for this thread and you should start a new topic for that if you are looking for help.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Guile »

vol.2 wrote:
I tried CEA mode 8 last year running Raspberry Pi OS with a self-compiled Retroarch binary and it worked fine on a RPi4 with a Portta HDMI-VGA adapter.
I will try that first and see if it works.

Is there any way to choose a resolution at boot or do you have to manually change the config.txt and reboot every time? It would be nice to be able to switch between using it on 240p for crts and 1080p for other tvs.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by vol.2 »

Manually enter the resolution in config.txt.


Best way to handle this is to first get the Pi setup to go headless and SSH into it. You can just use windows powershell to directly call "ssh user@ip" from the commandline and it's nbd.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Fudoh »

On anything with an Emulationstation frontend you can create a script file that changes between various config files and add that script to the menu system. I don't know if you can directly launch a script from Retroarch though.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Bahn Yuki »

Guile wrote:Is 240p not working well for the pi4? I ordered an hdmi to yuv converter to test. I looked into this months ago but saw some comments saying it didn't work without issues.

I saw a few different suggested configs, can anyone confirm one that works decently for 240p hdmi output on a pi4?

I also have a pi zero but that would really limit what systems I could emulate.

Has anyone tried getting 240p out of a firestick or an old laptop? Maybe I can try CRU and see if that works.
hdmi_group=1
hdmi_mode=8
Works fine for me on the RPI4(latest nightly Lakka) with my HDMI to YPbPr adapter. Colors look a bit washed out due to excessive brightness and I've tried all the pixel encoding modes. I have to turn the brightness down on my TV to compensate.

Let me know if you can get Vulkan working on your end. Seems to fail for me on 240p, shame too because Vulkan gives a nice performance bump since Hard GPU sync is FREE. Using it normally(1080p) made a big difference in some cores.

https://www.youtube.com/watch?v=x85KnZIh4p8
Displays I currently own:
LG 83C1(OLED),LG 77C2(OLED), LG 42C2(OLED),TCL 75R635(MiniLED),Apple Studio Monitor 21(PCCRT),SONY 34XBR960x2(HDCRT)
SONY 32XBR250,Samsung UBJ590(LED),Panasonic P50VT20(Plasma),JVC NZ8
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by sedavenp »

Bahn Yuki wrote:
Guile wrote:Is 240p not working well for the pi4? I ordered an hdmi to yuv converter to test. I looked into this months ago but saw some comments saying it didn't work without issues.

I saw a few different suggested configs, can anyone confirm one that works decently for 240p hdmi output on a pi4?

I also have a pi zero but that would really limit what systems I could emulate.

Has anyone tried getting 240p out of a firestick or an old laptop? Maybe I can try CRU and see if that works.
hdmi_group=1
hdmi_mode=8
Works fine for me on the RPI4(latest nightly Lakka) with my HDMI to YPbPr adapter. Colors look a bit washed out due to excessive brightness and I've tried all the pixel encoding modes. I have to turn the brightness down on my TV to compensate.

Let me know if you can get Vulkan working on your end. Seems to fail for me on 240p, shame too because Vulkan gives a nice performance bump since Hard GPU sync is FREE. Using it normally(1080p) made a big difference in some cores.

https://www.youtube.com/watch?v=x85KnZIh4p8
Thank you Bahn Yuki! This worked for me. I think the issues that came up for me had to do with retropie and the emulationstation front end. Didn't run into any issues running the most recent lakka nightly build and hdmi_group=1 hdmi_mode=8. Can confirm that portta hdmi to vga -> sync combiner works well to get 240p rgbs from the pi 4.
Spoiler
Image
Didn't have any luck with Vulkan, only worked for me with the gl driver.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by vol.2 »

sedavenp wrote:I think the issues that came up for me had to do with retropie and the emulationstation front end.
RP is always problematic with this process because it's not designed to work with a CRT.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Guile »

I tried hdmi_group=1 hdmi_mode=8 with a pi4 and the StarTech hdmi converter to ypbpr and it did show up but with issues. First, for some reason on my tv the input osd does not go away so it's always showing "Input Component" on top.

When I start emulationstation the aspect ratios are way off so it's just a scrunched small image in the middle of the screen. I can't figure out how to properly adjust the image and all the presets don't look right. There was also pretty bad stuttering in NES which doesn't happen at 1080p.

I tried redream dreamcast emulator as well and it seems to output its own resolution so it wouldn't display normally.

I also tried with 240p output from the gbs control and at least it doesn't keep the osd message up.
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Guile »

Bahn Yuki wrote: hdmi_group=1
hdmi_mode=8
Works fine for me on the RPI4(latest nightly Lakka) with my HDMI to YPbPr adapter. Colors look a bit washed out due to excessive brightness and I've tried all the pixel encoding modes. I have to turn the brightness down on my TV to compensate.

Let me know if you can get Vulkan working on your end. Seems to fail for me on 240p, shame too because Vulkan gives a nice performance bump since Hard GPU sync is FREE. Using it normally(1080p) made a big difference in some cores.

https://www.youtube.com/watch?v=x85KnZIh4p8
sedavenp wrote:
Thank you Bahn Yuki! This worked for me. I think the issues that came up for me had to do with retropie and the emulationstation front end. Didn't run into any issues running the most recent lakka nightly build and hdmi_group=1 hdmi_mode=8. Can confirm that portta hdmi to vga -> sync combiner works well to get 240p rgbs from the pi 4.

Didn't have any luck with Vulkan, only worked for me with the gl driver.
I put Lakka on a separate SD card to test this out on my pi4 and it worked fine from 1080p hdmi but when I try to edit the config with hdmi_group=1 hdmi_mode=8, it looks like it has trouble booting. I connected it to my StarTech hdmi to ypbpr converter and it shows a garbled image via component. I can see the Lakka flower logo through the garbled mess but it looks like it resets and never gets to the blue retroarch screen.
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vol.2
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by vol.2 »

Guile wrote: I put Lakka on a separate SD card to test this out on my pi4 and it worked fine from 1080p hdmi but when I try to edit the config with hdmi_group=1 hdmi_mode=8, it looks like it has trouble booting. I connected it to my StarTech hdmi to ypbpr converter and it shows a garbled image via component. I can see the Lakka flower logo through the garbled mess but it looks like it resets and never gets to the blue retroarch screen.
You have to set Lakka to RGUI and change the resolution in video settings before you hook it up to the CRT.
Guile
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Re: 240p via HDMI on Raspberry Pi to RGBS, no need for RGB h

Post by Guile »

vol.2 wrote:
You have to set Lakka to RGUI and change the resolution in video settings before you hook it up to the CRT.
I changed it to RGUI and set the resolution to 2048x240 but I got the same result. It's just a bunch of horizontal lines with the lakka flower broken up and looking like it resets and tries to boot. I also tried this config https://www.retrorgb.com/rpi240p.html but again same result.

Maybe my converter isn't compatible or something else is going on.
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