Pi 4 + VGA666 + Ultimarc JPAC Issues


I am trying to get my Pi4 to work on my arcade setup but I’m having some issues with getting games to display without cutting out. I’m using a Pi4 with a VGA666 hat and connecting it all to the Ultimarc JPAC for my Arcade Jamma connection. I’m using the Lakka nightly build dated 11/04/2019. With this setup and my current config files I can get to the main menu via the VGA 666 overlay which allows me to set my button bindings and load games (and access any other settings). When I load a game (neo geo in this case) the picture cuts in and out and is mostly black. The monitor clicks every time that the picture cuts in and out (Wells Gardner D9202).

I’m hoping that someone can take a look at my distroconfig.txt and retroarch.cfg files and let me know what I need to adjust to make it work.

Here’s the distroconfig.txt: https://pastebin.com/42sPjpK6

Here’s the retroarch.cfg: https://pastebin.com/pM2u9k2i

Any help would be appreciated.

Thank you!

when it cuts in, is the image correct? out of sync?

It might be easier if I show a video of what it’s doing. The game picture is only on the screen for a short period of time and then it’s black most of the time. Even with this video I was only able to get a picture initially, it never came back. Here’s the video showing what it does when I load a game:

Could the recently announced upcoming Lakka update resolve my issue or do I need to modify my config files somehow?

It might. I’m not sure how far back Lakka is in RetroArch commits, but if it’s missing some of the needed switchres changes, it could indeed help.

Ok cool we’ll test it out then. I’ll report back if it resolves my issue or not.

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I just tried it with the latest and greatest version of Lakka and I’m having the same results as the video that I posted above. Everything boots up and I can get to the main menu. Once I load a game I get a garbled picture initially and then the monitor goes crazy trying to sync. I’ve looked everywhere for some guidance on this and I can’t find anything. Could it have something to do with any of these settings in the retroarch.cfg?

crt_switch_center_adjust = “0”

crt_switch_resolution = “1”

crt_switch_resolution_super = “1920”

crt_switch_resolution_use_custom_refresh_rate = “false”

crt_video_refresh_rate = “60.000000”

current_resolution_id = “0”

cursor_directory = “~/.config/retroarch/database/cursors”

custom_viewport_height = “224”

custom_viewport_width = “2048”

custom_viewport_x = “0”

custom_viewport_y = “8”

desktop_menu_enable = “true”

Looking at your video, this is a bad boot config. It also does not look like RetroArch has changed resolutions once booted either.

I do know there are issues with the new frame buffer driver used on the RPi4. This does cause resolutions to be a little off but not like your video.

I will check my config.txt over the weekend past it here for you.


That would be great, thank you!

Try the following.

hdmi_timings=320 1 20 29 35 224 1 10 14 16 0 0 0 60 0 6400000 1 # 320:224

With these settings I had worse results than before. I could not get to the main menu. The monitor did the same out of sync clicking and going black. So it’s behaving the same way up front as when I’m trying to load a game. Here’s what my distroconfig file looks like with this last update:

SPDX-License-Identifier: GPL-2.0-or-later

Copyright © 2019-present Team LibreELEC (https://libreelec.tv)


dtoverlay=vc4-fkms-v3d disable_splash=1 disable_overscan=1 dtparam=audio=on

#VGA 666 dtoverlay=vga666 enable_dpi_lcd=1 display_default_lcd=1 dpi_group=2 dpi_mode=87 hdmi_timings=320 1 20 29 35 224 1 10 14 16 0 0 0 60 0 6400000 1 # 320:224

Any other ideas?

Also, should I be adding this to the distroconfig or the config file? I can’t tell where this would go in the config file between all the other settings.

Here’s a video of what it’s doing with the last updates:

Is there no way to make this work? Is there a bug?