The Sharp X68000 uses some odd resolution when outputting in 31khz. The TV is saying 640×512, and that’s also what the “advanced timings” section of the OSSC defaults to when the X68000 is in 31khz mode.
Basically, some X68000 games can be changed to run at 15khz and they look far sharper at line 4x than ‘512p’ only game does on passthrough. It’d be great if it could line double to 1024p. Unsure how many displays would support, but my Toshiba HDTV seems to throw every weird thing I throw at it.
EDIT: As I’m unsure if you own a X68000 to test with, I’d be glad to provide any additional needed information or perform testing to help out.
Since I’m still trying to get my head fully around the OSSC, would it make sense to also explicitly support native X68000 resolutions 512×512 and 512×256? With 640×512 I’m able to adjust vertical size and position of the X68000 image, but not horizontal size & position. Would supporting these native resolutions enable that?