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A recent commit seems to have broken "something" related to the analogue sync signal #30

Closed semi-simple closed 6 months ago

semi-simple commented 6 months ago

I suspect that commit 44837391db57bbed3ee325d557492445ea8b27e7 broke "something" related to composite sync. I have not yet had time to debug the issue with an oscilloscope, but after a recent MiSTer update, I started having some sync issues on a consumer TV (Sony Trinitron). The image became "wobly" on some cores.

The setup is roughly: MiSTer to VGA to SCART adapter (https://etim.net.au/shop/shop.php?crn=220&rn=582&action=show_detail) to a RGB to YUV converter to a consumer TV. The VGA to SCART adapter does accept either a composite sync OR a separate H+V sync (which it would then combine into a composite sync for SCART).

My suspicion is that "something" changed that made the VGA to SCART adapter try to "combine" H + V even when composite_sync = 1 is set in mister.ini (i.e. even when "H" is already composite sync) while it didn't before.

On a PVM, the new sync signal works just fine, but it really trips my consumer TV and the image becomes wobly if composite_sync = 1.

Sorry for the poor quality bug report, I'll add more useful details when time allows, filing in case something obvious jumps out to you.

semi-simple commented 6 months ago

menu_20230223.rbf exhibit the same issues, so this is not it. Closing.