Hello Zhang,

It looks as though wsconsctl lets you control the display
mode used by a screen ('virtual console'). wsdisplay sits on
top of a hardware-specific display driver like vga, ega,
pcdisplay etc.  If I understand correctly, support for
additional screen modes would have to go into the display
driver (e.g. vga), which would then make them available to
wsdisplay.

As well as text modes, wsdisplay appears to work with some
display hardware that only supports bitmapped modes.  I'm
not sure yet whether the hardware-specific display driver or
wsdisplay is responsible for drawing characters on those
displays.  If the mode you want isn't available as a text
mode, it may be possible to emulate it in a graphics mode.
I imagine this would take some work, and there might be a
performance hit.

- Andy Ball.