Arcade Legends monitor issue

[VespaGuy]

Hey all. Not sure if this is the right place for this question... but here goes...

I have a friend with an Arcade Legends cab who contacted me because it wasn’t working. (I collect cabs and have built some Raspberry pi cabs from scratch, so he figured I’d be able to help diagnose and fix his cab)

His issues was a common one - the battery was dead. We hooked up a VGA monitor and keyboard, replaced the Cr2032, and reconfigured the BIOS based on the Arcade Legends instructions found online.

Once we exited and saved the BIOS, the VGA monitor should have gone to sleep - at which point we could reconnect the original monitor and everything should have worked perfectly.

Instead, once we exited and saved the BIOS, the Game booted right up and was visible on the VGA monitor. When we reconnected the original monitor (CGA) the screen was scrambled.

Anyone have any ideas what might be wrong? I don’t know enough about this stuff, but I’m assuming that the wrong signal is being sent to the monitor and I’m unsure how to change/fix that. Any help would be greatly appreciated.

[baritonomarchetto]

That's an out of frequency video signal, nothing more than that. The CRT monitor is ok and has no issues.

[VespaGuy]

Thank you. What’s the fix?

[baritonomarchetto]

If you are asking how to force that Legends Arcade video signal to low resolutions, I have not an answer I am sorry. You should contact them directly: your friend paid for that thing...

[Zebidee]

Looks like you have a 31khz video signal.

Set the game to CGA/15khz mode - I'm guessing you flipped a dip switch or something to enable VGA mode. Get a manual online somewhere, figure out which DIP and if it exists, then flip it.

Even so - Be aware that some boards with VGA out will only put VGA/31khz signals on their VGA port. The CGA/15khz might only be available from the JAMMA side.