Read the statement by Michael Teeuw here.
Rpi 4 and two monitors
-
@sdetweil , so using ‘0’ or ‘0.0’ give the same result and start MM on the first monitor.
So far I have tried 1,2,3,4,5,6,7,8,9 and 0.1, 0.2, 0.3, 0.4, 0.5
How far do I go? :)
-
@NathTheDude The 2nd monitor should be display 0, screen 1. Use this:
DISPLAY=:0.1 -
Hey @OldSunGuy , thanks. ‘0’ and ‘0.0’ seem to be the first monitor however I get an error when I try anything else. So far I have tried using each of the following: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9
Each time I try to start npm (npm start) apart from when I use 0 or 0.0 I get the following (with the value reflecting the number I changed in ‘run-start.sh’):
(electron:2238): Gtk-WARNING **: 06:14:02.236: cannot open display: :0.1@sdetweil - not sure if this is relevant but it does not seem to matter what value I set in ‘run-start.sh’, when I reboot the pi it will always start MM on the first screen. Should it not fail if it is using ‘run-start.sh’?
Also with an incorrect value being added to ‘run-start.sh’, when I run ‘mm.sh’ this always works and displays MM on the first screen.
okay, I think I understand it now. When I reboot it is using ‘mm.sh’, within mm.sh is the following:
cd ~/MagicMirror DISPLAY=:0 npm startWhich I assume means that the ‘run-start.sh’ is not used during boot up?
When I change this value to anything other than 0, this will also fail with the same error seen when trying to run npm previously.
-
@NathTheDude If you start a terminal on one desktop and run:
echo $DISPLAYThen start a terminal on the other desktop and run:
echo $DISPLAYdo you get the same results?
-
@OldSunGuy - I get :0.0
I wonder if both screens are being seen as 0.0, if that is the case I guess I would expect the MM screen to cover both screens and not just the first :-/
-
@OldSunGuy , sorry mis read your comment. Not sure how I would start a terminal on one screen and a different terminal on another.
-
@NathTheDude if they are two independent desktops, then you should have a menu on the second desktop, just like the first…
also, you can move the mouse to the second desktop and do ctrl-alt-t to open a terminal there
I have an micro hdmi adapter coming later today so I can put up a second physical display on my pi4…
-
@sdetweil , I opened up a terminal session on each screen and both indicated the same display was being used (:0).
From the ‘Appearance Settings’ window (‘Prefences’ > ‘Apprearance Settings’, there is a ‘Taskbar’ tab and in this tab you select which hdmi output you want the taskbar to be on. You can choose both.
-
@NathTheDude so, it looks like one big desktop…
u should be using Buster OS, right? so you can see the temples across the big image, some on the right display, some on the left…
NOT the same on both?
-
@sdetweil , yeah buster.
I can see temples on both screens, the image does not flow between screens. When looking at the 'Appearance Settings’, the is a tab for each HMDI with different settings but these are purely for what image is seen on the desktop. You can use the same image on both desktops however this is purely related to the desktop image or so is what I understand of it.
-
@NathTheDude said in Rpi 4 and two monitors:
@sdetweil , I opened up a terminal session on each screen and both indicated the same display was being used (:0).
From the ‘Appearance Settings’ window (‘Prefences’ > ‘Apprearance Settings’, there is a ‘Taskbar’ tab and in this tab you select which hdmi output you want the taskbar to be on. You can choose both.
Sorry, with my previous comment - I meant to say you ‘CANT’ choose both (taskbar can only be on one screen/output).
-
@NathTheDude there is a firmware update on the pi4… execute
sudo rpi-update -
@sdetweil , so I did the firmware update and rebooted.
Slightly different now but still can not quite get this to work. When I now run a terminal on screen 1 the output of ‘echo $DISPLAY’ is ‘:0.0’ and when I run the terminal on the 2nd window the output is ‘:0’. However the same is seen when I try to either user ‘0’ or ‘0.0’ in run.sh (mm gets display on the 1st monitor.
I have again tried to use different numbers (1,2,3 and 0.1, 0.2, 0.3) but again, these are not valid entries.
-
@NathTheDude how about the output of xrandr -q
-
@sdetweil . I get the following when trying to run different xrandr commands:
Can't open display -
@sdetweil - ahhh. I need to do this from the desktop:
pi@MagicMirrors:~ $ xrandr -q Screen 0: minimum 320 x 200, current 2160 x 1920, maximum 7680 x 7680 HDMI-1 connected primary 1080x1920+0+0 left (normal left inverted right x axis y axis) 477mm x 268mm 1920x1080 60.00*+ 60.00 50.00 59.94 1680x1050 59.88 1280x1024 75.02 60.02 1440x900 59.90 1280x960 60.00 1280x720 60.00 60.00 50.00 59.94 1024x768 75.03 70.07 60.00 832x624 74.55 800x600 72.19 75.00 60.32 56.25 720x576 50.00 50.00 50.00 720x480 60.00 60.00 59.94 59.94 59.94 640x480 75.00 72.81 66.67 60.00 59.94 59.94 720x400 70.08 HDMI-2 connected 1080x1920+1080+0 right (normal left inverted right x axis y axis) 477mm x 268mm 1920x1080 60.00*+ 60.00 50.00 59.94 1680x1050 59.88 1280x1024 75.02 60.02 1440x900 59.90 1280x960 60.00 1280x720 60.00 60.00 50.00 59.94 1024x768 75.03 70.07 60.00 832x624 74.55 800x600 72.19 75.00 60.32 56.25 720x576 50.00 50.00 50.00 720x480 60.00 60.00 59.94 59.94 59.94 640x480 75.00 72.81 66.67 60.00 59.94 59.94 720x400 70.08 pi@MagicMirrors:~ $ -
@NathTheDude ok, I can see the same results now that I have my adapter…
may have to wait til tomorrow to work on it…
-
Hey @sdetweil , no problem at all - no rush indeed. Thank you for your help thus far.
So thanks to this page I have been able to run up two chromiums, one on each page but I have started up chromium directly via terminal from the desktop. Not quite figured out how to implement this as two MM’s and if running up two at once would kill the CPU.
1st terminal session
DISPLAY=:0 /usr/bin/chromium-browser \ --noerrdialogs \ --kiosk \ --window-position=0,0 \ --start-fullscreen \ --user-data-dir=Default2nd terminal session
DISPLAY=:0 /usr/bin/chromium-browser \ --noerrdialogs \ --kiosk \ --window-position=1920,0 \ --start-fullscreen \ --user-data-dir=‘Test2’ -
@NathTheDude copy one MM folder tree to MagicMirror1
then change the config on MM1 to use a different port (8081 maybe)
then start both MM in serverOnly mode (u can set that in config.js too, serverOnly: true,
then launch your two browsers, with the url pointing to separate MM’s…
–app=http://localhost:MM_port,
–app=http://localhost:MM1_portyou can edit the run-start.sh on MM1 to add the
--window-position=1920,0 \ --user-data-dir=‘Test2’parms to the ones already provided
then change both MM configs to serverOnly: “local”,
and it will launch the chrome browser for you
(this is what we call split mode, using a separate browser)then u can have pm2 start both of those when the system boots…
have to change the mm.sh in MM1/installers, and maybe the json file title to MagicMirror1, and point to the local mm.sh -
Hey @sdetweil , thanks for the info on this - I am grateful.
I think I am nearly there but just missing a bit or two.
I copied the ‘MagicMirror’ to ‘MagicMirror2’ folder, updated the config.js, run-start.sh and the pm2_MagicMirror.json files.
When I reboot I now get MM and MM2 load up but both on the same screen.
I have messed around with the chromium line from the ‘run-start.sh’ and I don’t think it is actually be used in this case, I even commented the line out and this did not prevent me from running ‘npm start’ and MM2 still loaded albeit on top of the first MM.
Any ideas on where it is getting it’s info on how to start up chromium?
Thanks
Nathan
Hello! It looks like you're interested in this conversation, but you don't have an account yet.
Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.
With your input, this post could be even better 💗
Register Login