When running multiple screens on KDE with SDDM, your configuration will not be loaded until you actually login to the KDE desktop, so you might end up having screens out of order, or enabled/disabled when they should not be. To fix this is simple, and here’s how.
Let’s get a list of the devices name, size and position with xrandr:
$ xrandr | grep ' connected'
DP-1 connected (normal left inverted right x axis y axis)
DP-3 connected 1920x1080+1920+0 (normal left inverted right x axis y axis) 480mm x 270mm
DP-5 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 598mm x 337mm
As you can see, on my computer I have 3x monitors:
DP-1 - Connected on the first port but disabled
DP-3 - My secondary monitor; Resolution 1920x1080; position 1920x0
DP-5 - My main monitor; Resolution 1920x1080; position 0x0
So we will start by adding the right configuration to /usr/share/sddm/scripts/Xsetup
$ sudo vim /usr/share/sddm/scripts/Xsetup
#!/bin/sh
# Xsetup - run as root before the login dialog appears
xrandr --output DP-1 --off
xrandr --output DP-5 --mode 1920x1080 --pos 0x0 --rotate normal --output DP-3 --mode 1920x1080 --pos 1920x0 --rotate normal
Explanation:
The first line disables the monitor connected to the first port xrandr --output DP-1 --off
The second line sets the right dimension and position for my other two monitors
Now we need to add the config to SDDM:
$ sudo vim /etc/sddm.conf
[XDisplay]
# Xsetup script path
# A script to execute when starting the display server
DisplayCommand=/usr/share/sddm/scripts/Xsetup
And now a simple reboot will take care of the changes:
Simple instructions (assuming a new Raspbian install) to install Kuman 3.5 TFT LCD on Raspberry Pi 3 Model B.
a. Download Rasbian strech (with desktop) and extract the .img file from the downloaded zip (it’s always good to also check the hash of the downloaded file)
b. Insert the SD card and make note of the device being used (make sure you get this right not to overwrite your OS)
c. Use dd to copy the image to the SD card (the values for if and of should be changed accordingly. If you never used dd please do yourself a favor and read up first)
d. Once the process is done, mount (if needed) the boot and rootfs partitions
e. Browse to the mount point of boot and create a blank file called ssh (to enable sshd on boot)
touch ssh
f. Open cmdline.txt and write down the value of root=. Now substitute the existing line with the line below, and then change the value of root= back to the original value
Quick instructions on how to create a simple systemd user service for a program or script.
1- Identify the script or program/binary that you will be using
2- Create a systemd unit file using the example below, give it a name that will make sense to you with a .service extension (like [my_service].service), and save it to $USER/.config/systemd/user
After commuting close to 1000kms a week for 6 years, I have decided to the the leap and move to Toronto. After all, I was here around 4 nights a week, and having to commute back and forward between Mississauga and Toronto had become a hassle. This would also increase my work drive (from 85kms each way to 115kms), but luckily my client agreed for me to work remote 4 days of the week, with made my move even more possible.
Seeing how I would be working from home most of the week, and how my office would be in the living room of our new place, I needed a space that not only was functional, but that could hold my three 27” monitors have have a clean look. I also wanted a standing desk because I can no longer get used to sitting the whole day.
After searching pinterest and online for ideas, I finally had a plan and knew what parts I would need.
And here’s the final work:
The Wall
The space I had was perfect. The back wall has the length of 64”, with 4 wood studs distributed evenly with 16” of space. The side wall had a stud 13” away from the corner, and another stud 16” away from it. I needed to leave space for the cabling since I did not want to bring it through the wall. Space was needed on the left for my NAS cables to go through, and in the middle for the cables coming down from the monitors, LEDs and keyboard and mouse.
The Monitor Mount
For the monitors I purchased the 3x mounts below on Amazon. I have the two main monitors mounted to a piece of plywood, which is in turn attached to the wall.
I’m using a custom bash script running on the background that checks if my monitors are on or off, and turns on the lights via curl commands to a Wemo Switch:
