Problem with switching displays

[Charriu]

Hi all,

Right now I'm working on a little project. I want to build me a recalbox handheld which I still can connect to a TV or Monitor. Think the Nintendo Switch and you know what I want to do.

I already bought myself a display (http://wiki.52pi.com/index.php/5-Inch-800x480-Capacitive-Touch-Screen_SKU:_EP-0081) and got it working with the mentioned settings in /boot/config.txt:

framebuffer_width=800
framebuffer_height=480
hdmi_force_hotplug=1
hdmi_group=2
hdmi_mode=87
hdmi_cvt 800 480 60 6 0 0 0

My problem is that when I now connect the pi with my TV and not the display, I get a black screen after the boot screen. Obviously this is because I forced a resolution and other settings, which my TV can't display.
So now I'm wondering if there is an easy way to turn off these settings, when I don't use my handheld display?
Or maybe there is a better way to automatically recognize my handheld display? When I don't use these settings it displays in 640x480 with a big black border on the left.

Thanks for your help and advice so far.