Game Boy Adcance - crt switchres - resolution question

General
#1

Hi all,

Quick question,

I am curently experimenting with the gba cores in retroarch linux (mgba and vba next) to display the games on my crt using the switchres functionality

I noticed that i have two massive black bars above and below the screen.(i know the aspect ratio of the gba is not 4x3 but more 1.66)

Cheching the video output I noticed that instead of sending 160 or so vertical lines to match the gba the graphic card outputs 200 lines.

Is this a limitation within swhitchres (For instance the lowest vertical res is 200) or is there another potential issue somewhere ?

If this is linked to switchres, is there a way to manually add a resolution to match the gba ?

Thank you in advance :slight_smile:

#2

Most GPUs won’t accept resolutions lower than ~200 lines, so switchres pads to 200 for cores that output lower than that.

If you run GBA at 240p through a real gamecube gameboy player, you’ll get the same big black borders (bigger, actually, since it pads to 240).

#3

Oh ok. I guess I’ll ouput gba and other below 200 lines systems to some 15khz monitors i have and manualy stretch the picture verticaly.

Thanks again for taking the time to respond :slight_smile:

#4

I never tried to determine any limits for active lines, but shouldn’t the relevant number for borders and limits be related to the total lines not active ones? It seems you can’t go much lower than 250 lines total unless you increase refreshrate over 60Hz or go below 15 kHz frequency.