树莓派hdmi配置参数

hdmi_cvt=
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

tvservice -m DMT

hdmi_group=2
hdmi_mode=87

to make the custom mode the default.

Please note. There is no guarantee your display will support the resolution/framerate produced by this. 
But if you are currently running a monitor at a non native resolution, then this may be worth a try.

The hdmi_timings parameters are:

hdmi_timings=

在配置1440×2560的屏幕时本以为树莓派只支持横屏的，所以设置完hdmi_cvt=2560 1440 50 后再利用display_rotate=1；

其实不然，直接hdmi_cvt=1440 2560 50即可不用再反转

另外由于显示模式是用户自定义所以设置hdmi_group=2  hdmi_mode=87