<div dir="ltr"><div>You can use the old style of options to rotate the screen:</div><div> </div><div>DISPLAY=:0 xrandr -o left </div></div> <div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Dec 20, 2019 at 7:51 AM djh <<a href="mailto:xorg@howorth.org.uk">xorg@howorth.org.uk</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">I've just attached a display to a Pi 3B+. It's an old display attached through a VGA-HDMI converter (no idea whether that's relevant!). I've also attached a USB keyboard, though not yet a mouse. I want to run the display in portrait mode. When I booted it came up sideways (in landscape mode) as I expected. I started trying to use xrandr via ssh to configure the display but haven't figured out how to get it to work. Here's a sample of some output: $ xrandr -display :0 --prop xrandr: Failed to get size of gamma for output default Screen 0: minimum 1280 x 1024, current 1280 x 1024, maximum 1280 x 1024 default connected 1280x1024+0+0 0mm x 0mm non-desktop: 0 supported: 0, 1 1280x1024 0.00* $ xrandr -display :0 --output 'default' --rotate left xrandr: output default cannot use rotation "left" reflection "none" I searched but haven't found any articles that explain my problem. So I thought I'd try lxrandr instead. That pops up a dialog box on screen saying "Unable to get monitor information!" and prints an error on the command line: $ lxrandr --display :0 Can't open display Somebody then told me how to rotate it 'the pi way', by editing /boot/config.txt That worked, but I'd like to understand why the X way doesn't. I'm also unable to access the display remotely. From my ssh session on the pi I can launch xeyes for example: $ DISPLAY=:0 xeyes ^C # terminate from keyboard and I turned off access control: $ DISPLAY=:0 xhost + access control disabled, clients can connect from any host But I can't connect to the pi from another host: $ DISPLAY=RpiBplus:0 xeyes Error: Can't open display: RpiBplus:0 $ ping RpiBplus PING RpiBplus.fritz.box (192.168.1.22) 56(84) bytes of data. 64 bytes from RpiBplus.fritz.box (192.168.1.22): icmp_seq=1 ttl=64 time=0.314 ms $ DISPLAY=<a href="http://192.168.1.22:0" rel="noreferrer" target="_blank">192.168.1.22:0</a> xeyes Error: Can't open display: <a href="http://192.168.1.22:0" rel="noreferrer" target="_blank">192.168.1.22:0</a> I'd appreciate any suggestion for places to look to explain this mystery to me, or actual solutions of course :) Thanks, Dave _______________________________________________ <a href="mailto:xorg@lists.x.org" target="_blank">xorg@lists.x.org</a>: X.Org support Archives: <a href="http://lists.freedesktop.org/archives/xorg" rel="noreferrer" target="_blank">http://lists.freedesktop.org/archives/xorg</a> Info: <a href="https://lists.x.org/mailman/listinfo/xorg" rel="noreferrer" target="_blank">https://lists.x.org/mailman/listinfo/xorg</a> Your subscription address: %(user_address)s </blockquote></div>