28 Mar 2018, 11:19

@greed
you can try with hdmi cvt in the config.txt :
https://www.raspberrypi.org/forums/viewtopic.php?t=24679
something like this, with your own resolution :

hdmi_cvt=1920 240 60 1 1 0 0

info on numbers :

hdmi_cvt=<width> <height> <framerate> <aspect> <margins> <interlace> <rb>
width        width in pixels
height       height in pixels
framerate    framerate in Hz
aspect       aspect ratio 1=4:3, 2=14:9, 3=16:9, 4=5:4, 5=16:10, 6=15:9
margins      0=margins disabled, 1=margins enabled
interlace    0=progressive, 1=interlaced
rb           0=normal, 1=reduced blanking

and you need to setup the boot in this custom mode, in the config.txt :

hdmi_group=2
hdmi_mode=87

(custom mode is on mode 87)
in recalbox.conf, you should put

global.videomode=default

or

global.videomode=DMT 87 HDMI

I think the default should work.