Hi,
I know it’s a strange question, but I’ve installed 2 monitors vertically and the top monitor is inverted. I’ve already changed LighDM to have the monitors with the correct image and I’ve chosen the main monitor, but I don’t know how to change grub to have one of the monitors with an inverted image, so that during grub and boot, the monitor shows the correct image or, in the last case, the inverted monitor has no image and only does when you switch to LightDM.
I know that the boot time is minimal and this modification unnecessary, but I’d like to know if it’s possible to change it.
I’ve been reading about grub, but I can’t find how to use 2 monitors in grub and even invert one of them or that one of them has no image. All I’ve found is that “it’s not possible”.
This is the installation I have and the current grub and boot image:
Hi Jorge,
The display of the grub menu is, I think, done my the primitive
VGA driver in the BIOS. It is only when Linux boots that the graphic display drivers ( including dual monitor controls) become active.
So I am afraid it might indeed be impossible or very difficult.
Does it really matter for grub? You should be able to fix it
once linux boots.
For grub it’s not very important, but for the boot, it makes me a bit confused, but as I said, the boot time is minimal, it was just putting the monitors with the correct image from the start.
I’m going to forget about grub and just keep looking at how to invert the boot image.
Well, I think I’ve found a clue: I was just connecting to the graphics, LightDM and Desktop, but I’ve just discovered that the virtual consoles are still reversed.
Looks like I’ll have to study up on fbcon (framebuffer console).
But when I change to virtual console, for example, pressing CTRL+ALT+F1, I still have the top image without correction, i.e., xrandr is only for the graphics part:
László,
this is the UEFI image, where you can see that it is inverted, but as I mentioned above, it is normal, because the top monitor is physically inverted:
Oh, I understand now.
I did not read it carefully before, I thought there’s some problem with the graphics card.
My bad.
In this case the correct way to adapt is to use display rotation within X11 (set up via xrandr as you did).
For the console I found the fbcon configuration, which you already found as well.
I use 2 monitors too, because my everyday task does not fit on one…
I guess @Tech_JA is in the same boat, he needs the screen surface.
I have my monitors in a side by side (quite trivial) setup.
I think the problem is that he has the upper monitor 180 degree rotated, which is impossible to rotate back (why?).
As I digged more into the question the fbcon solution doesn’t work either.
As I understand it will rotate the the console, but for all outputs, so the upper monitor gets normal, but at the same time the lower gets upside-down.
I’d try my best to make both monitors to have the same orientation.
Hi Neville,
I don’t know if your question refers to placing the monitors vertically or placing the top monitor upside down, so I’ll answer both possible questions:
Installing the 2 monitors vertically: because I don’t have space to place them horizontally, as László mentioned having his monitors
why I installed the top screen upside down: if I put it in the normal position, I wouldn’t have access to the keys, but the worst thing for me is that the bottom of the bezel creates a larger screen space than if it were upside down.
