I'm running a custom version of raspbian on my raspberry pi, it has no X server running only in text mode with only basic services installed. i got a usb monitor that i want to plug in and use to show the console, i plugged it in it's detected and showing a green screen but i'm not sure what i can do to achieve my goal if that's even possible. Any of you can give some pointers ?

dmesg log:

[ 1606.712232] udlfb: DisplayLink LILLIPUT USB Monitor - serial #70873920033
[ 1606.724237] udlfb: vid_17e9&pid_02a9&rev_0130 driver's dlfb_data struct at b8d6d800
[ 1606.741459] udlfb: console enable=1
[ 1606.749754] udlfb: fb_defio enable=1
[ 1606.757827] udlfb: shadow enable=1
[ 1606.766183] udlfb: vendor descriptor length:17 data:17 5f 01 00 15 05 00 01 03 00 04
[ 1606.782954] udlfb: DL chip limited to 1500000 pixel modes
[ 1606.794348] udlfb: allocated 4 65024 byte urbs
[ 1606.885797] udlfb: 800x480 @ 59 Hz valid mode
[ 1606.894588] udlfb: Reallocating framebuffer. Addresses will change!
[ 1606.906132] udlfb: 800x480 @ 59 Hz valid mode
[ 1606.914741] udlfb: set_par mode 800x480
[ 1606.927843] udlfb: DisplayLink USB device /dev/fb1 attached. 800x480 resolution. Using 1504K framebuffer memory
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    It's funny that the answers in the "duplicate" don't actually mention con2fbmap, which was important for the solution... – dirkt Jul 5 '18 at 5:44

/dev/fb1 means it gives you a framebuffer device (here is the kernel API documentation). So you can use any software that can use such a framebuffer device (there's a number of them, e.g. picture viewers, or terminals).

Linux consoles use framebuffer devices via fbcon, and there's a parameter map to specify which consoles work on which framebuffer devices.

I haven't tried this myself (because I only have a single framebuffer device), but I'd assume by booting with this argument, one should be able to put a number of Linux consoles on your USB monitor. Alternatively, use con2fbmap to change the assignment after boot.

Unless of course you find it easier to use applications directly on the framebuffer, like starting a framebuffer terminal emulator.

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    didn't know it was this easy, after installing apt-get install fbset and running con2fbmap 1 1 everything working now. appreciate the help – Tychus Jul 4 '18 at 9:35

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