By default, Digi Embedded for Android configures HDMI as the primary video interface. You can override the configuration by using the video variable in the U-Boot environment.

HDMI only (default)

=> setenv video video=mxcfb0:dev=hdmi,1920x1080M@60 video=mxcfb1:off video=mxcfb2:off video=mxcfb3:off
=> saveenv

LVDS only

=> setenv video video=mxcfb0:dev=ldb,bpp=16,if=RGB666 video=mxcfb1:off video=mxcfb2:off video=mxcfb3:off
=> saveenv

LVDS primary and HDMI secondary

=> setenv video video=mxcfb0:dev=ldb,bpp=16,if=RGB666 video=mxcfb1:dev=hdmi,1920x1080M@60 video=mxcfb2:off video=mxcfb3:off
=> saveenv

HDMI primary and LVDS secondary

=> setenv video video=mxcfb0:dev=hdmi,1920x1080M@60 video=mxcfb1:dev=ldb,bpp=16,if=RGB666 video=mxcfb2:off video=mxcfb3:off
=> saveenv

Dual LVDS

=> setenv video video=mxcfb0:dev=ldb,bpp=16,if=RGB666 video=mxcfb1:dev=ldb,bpp=16,if=RGB666 video=mxcfb2:off video=mxcfb3:off
=> saveenv