Qt4 on HDMI

tcchan
I bought a Tiny210 with LCD resolution 800x480. I compile some QT4 apps and
they all run with resolution of 800x480, as expected as I use
QWS_DISPLAY=LinuxFb:/dev/fb0.  

The question is: 

Is it possible to run the QT app on the HDMI display (i.e., with resolution
like 1080x720, etc.)?  It is acceptable even the display is no shown in the
LCD and only shown on the HDMI output( best it can show a scaled version on
the LCD too).