tty - dual monitors

Question

I have a dual monitor setup running TTY only. The primary monitor is the actual "laptop", and the second monitor (Lilliput um-70) is connected through USB 2.0, using udl driver.

Everything is working fine, except for one thing, whenever I change TTY, the old TTY stops refreshing itself.

tty1 is mapped to /dev/fb0, tty2 is mapped to /dev/fb1 using kernel parameters during boot (fbcon=map:01). When I change to tty1 (laptop monitor), tty2 (USB monitor) stops refreshing.

For example, if I put an htop on tty2, going back to tty1 to do some stuff, the htop on tty2 freezes. If I go back to tty2, it refreshes itself, but tty1 now stops refreshing.

Any ideas on how to have tty1 and tty2 staying refreshed, no matter which TTY is active?

How do you switch between tty1 and tty2? with ALT+CTRL+F[1-2]? — NetIceCat, Dec 12 '19 at 04:21
Is your parameter fbcon=map:01? Because if so, try fbcon=map:10, or even fbcon=map:1 and then try mapping the consoles with con2fbmap afterwards — NetIceCat, Dec 12 '19 at 14:34
Do you mean that this will fix the refreshing problem? I will try it when coming home. — user1261558, Dec 12 '19 at 15:11
By that, do you mean assigning the terminals with con2fbmap after the reboot? What do you get when you use fbset -i from each console? — NetIceCat, Dec 14 '19 at 19:38
just found a way to do this. I am using yaft as the framebuffer terminal (https://github.com/uobikiemukot/yaft). This framebuffer console allow refreshing. — user1261558, Dec 14 '19 at 20:33

score 2 · Accepted Answer · answered Dec 14 '19 at 20:35

One way to do this is to use a frambuffer terminal like Yaft (https://github.com/uobikiemukot/yaft).

This needs to be compiled with the config

BACKGROUND_DRAW = true

in the conf.h file.

This allows for refreshing of the VT even if the VTs are inactive. For my specific hardware setup, I had to use the driver "udlfb" and NOT the newer driver "udl".

tty - dual monitors

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