An demonstration of the Morph 4K downscaling 1080p and upscaling 240p both to 540p! Here are the modelines for you to try out!
[NTSC]
custom1=540p,2200,1920,88,148,44,562,540,2,15,5,1,1,1.0,0,0
custom2=540p?,2200,1868,118,170,44,562,525,8,24,5,1,1,1.0,0,0