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ao486 garbled text and no good image on VGA CRT

Posted: Mon Jan 02, 2023 9:19 pm
by anderse77

Text is garbled on ao486 on VGA crt display. Image is looking like below. Any ideas what is wrong?

IMG_1519.jpg
IMG_1519.jpg (1.32 MiB) Viewed 1104 times

Re: ao486 garbled text and no good image on VGA CRT

Posted: Tue Jan 03, 2023 1:17 am
by bbond007

It almost seems like you need to use the monitor's controls to move the image further to the right...

do you have vga_scaler=1 set in your MiSTer.INI in the [AO486] section. Unless something has changed, ao486 really needs to use the scaler.

If post your MiSTer.INI maybe someone will be able to assist.

BTW, NICE CRT :)


Re: ao486 garbled text and no good image on VGA CRT

Posted: Tue Jan 03, 2023 1:59 am
by FoxbatStargazer

direct_video=0
video_mode=1440,400,70,cvt
in core menu video options, aspect ratio=full

Give that a try for starters.


Re: ao486 garbled text and no good image on VGA CRT

Posted: Tue Jan 03, 2023 7:17 am
by anderse77

Thanks. Here is my ini file. 1440x400 is not listed in this monitors manual. Isn't there a risk to damage monitor with arbitrary video_modes or is it safe to try?


Re: ao486 garbled text and no good image on VGA CRT

Posted: Tue Jan 03, 2023 7:21 am
by anderse77

Cannot post ini file. both txt and ini is invalid extensions


Re: ao486 garbled text and no good image on VGA CRT

Posted: Tue Jan 03, 2023 8:39 am
by FoxbatStargazer

horizontal resolution is pretty arbitrary and meaningless with regards to the limits of CRTs. I made it ultra-wide so it would be 2x 720 (for dos text) and 4.5x 320 for a decent low-res gaming experience. You can try 720x400 instead if you like. Eventually you can individually dial in each resolution but this is just to see if we can get something usable to start.

And you should probably put this stuff in [ao486] so its specific to just that core. Try sticking this at the end of your ini

Code: Select all

[ao486]
direct_video=0
forced_scandoubler=0
video_mode=1440,400,70,cvt

don't forget to change the aspect ratio to full in the core's menu.


Re: ao486 garbled text and no good image on VGA CRT

Posted: Tue Jan 03, 2023 11:34 am
by anderse77

video_mode=1440,400,70,cvt gives me sync out of range on this monitor. Smallest resolution is 640x480, I think


Re: ao486 garbled text and no good image on VGA CRT

Posted: Tue Jan 03, 2023 12:45 pm
by anderse77

tried
[ao486]
forced_scandoubler=0
direct_video=0
video_mode=1024,48,96,208,768,1,3,36,150000,+hsync,+vsync

it works and looks nice, however since core output is 720x400, shouldn't picture be distorted in games?