Thanks Roger for your response, replies interspersed: On Sun, May 8, 2016 at 1:46 PM, Roger <[email protected]> wrote: > Can you used an F key that switches from one monitor to overcome the > difficulty?
Yes, that's the workaround based on Victor's response: Control-Alt-F1 to get to to a virtual terminal, then power off monitor. On return, power-on monitor, then Control-Alt-V7 to get to x windows. > > What kind of cable / "monitor" do you have? I have a monitor that can serve HDMI. https://en.wikipedia.org/wiki/HDMI The wikipedia article says it is proprietary which i did not know. It works fine with Ubuntu 15.10 (and several earlier versions), but i've run into a couple of issues with xubuntu 16.04. > as a TV. It even has a remote control. I had to get a DVI cable to make my > monitor work correctly, from Amazon: > > http://tinyurl.com/hdn7ss9 > > Some times things are just weird! > They sure seem to be, but hoping to get some light shed on this one. dan > > On May 8, 2016 3:57:47 PM EDT, Dan Hitt <[email protected]> wrote: >> >> Ah Victor thanks a million! >> >> Turning off the monitor turns out to be key. >> >> If i turn off the HDMI monitor, lightdm (or whatever the underlying >> service is) seems to take that as a signal to never return. >> >> So that means that there is a work around. First, do ctrl-alt-f1 to >> get into a virtual monitor. Then turn off the monitor. >> >> And coming back, just do the reverse: turn on the monitor, then do >> ctrl-alt-f7 to get back xwindows. >> >> This is possibly related to another problem that i have, where i >> cannot listen to headphones plugged into my hdmi monitor. (Under >> ubuntu 15.10 i could do this, so i know it is not a hardware problem.) >> >> Now, unfortunately, i'm far too ignorant to have any ideas about your >> question "with modern lcd monitors is there any difference between >> sleep and a software shut off?" >> >> But i think it would be useful to know in order to construct some >> sort >> of model of how hdmi works (what states can a monitor be in, and what >> transitions are possible under what conditions between the states). >> >> Anyhow, thanks again for your help! (And thanks everybody else also. >> I've learned something from every suggestion.) >> >> dan >> >> >> On Sun, May 8, 2016 at 11:32 AM, Victor Forberger >> <[email protected]> wrote: >>> >>> On 05/08/2016 11:52 AM, Dan Hitt wrote: >>>> >>>> On Sun, May 8, 2016 at 5:07 AM, Petter Adsen <[email protected]> wrote: >>>>> >>>>> On Sat, 7 May 2016 20:32:03 -0700 >>>>> Dan Hitt <[email protected]> wrote: >>>> >>>> ..... >>>>>> >>>>>> Occasionally after i lock the screen and come back after a few hours >>>>>> i >>>>>> cannot get it to respond. >>>>>> >>>>>> The machine is alive, and i can ssh into from another host. >>>>>> >>>>>> But wiggling the mouse and pressing keys leaves the monitor pitch >>>>>> black. >>>> >>>> ..... >>>>> >>>>> >>>>> If you don't mind restarting your entire X session, you can try 'sudo >>>>> systemctl restart lightdm.service'. You could also try to kill the >>>>> screen locker process, I think Xfce uses light locker by default. >>>> >>>> >>>> >>>> Thanks Petter! >>>> >>>> So the problem came up again >>>> after i last wrote (i had to go do some >>>> chores, and when i came back keyboarding and mousing did not bring >>>> back the display). >>>> >>>> So i tried your suggestion of restarting lightdm. >>>> >>>> And it worked, so thanks! >>>> >>>> I did lose my X state, but i don't think any other state. >>>> >>>> This seems to indicate that lightdm is going into too deep a sleep, or >>>> perhaps taking something to sleep with it that should stay awake. >>>> >>>> If anybody has any advice about how to approach this kind of lightdm >>>> problem, i'm all ears --- although i know next-to-nothing about >>>> lightdm. >>>> >>>> Thanks again everybody for all the suggestions. They were all helpful. >>>> >>>> dan >>> >>> >>> I had a similar problem a ways back. I'm sorry if I can't pull up >>> specific info from my past problem-solving (I searched through various >>> logs in /var/log for log entries that identified what the problem was). >>> >>> But, I do recall >>> the problem was actually related to the monitor being >>> shut off (as opposed to just dimmed). When unlocking the computer for >>> use after a long delay, the process for turning the monitor back on was >>> not working. I fixed the problem by changing power manager settings so >>> that the display was never turned off, only put to sleep. Once that >>> setting was changed, lightlocker could activate the monitor again once >>> the session was unlocked. >>> >>> Restarting lightdm certainly will also do the trick. But, it is a >>> radical solution, especially if the problem is just related to getting >>> the monitor to connect to the xfce window manager (note that xfce runs >>> on top of lightdm -- i.e., lightdm provides the login screen when the >>> computer is turned on; xfce is the actual desktop environment for >>> getting work done after a successful login). >>> >>> And, one question here: with modern lcd monitors is there any difference >>> between >>> sleep and a software shut off? >>> >>> - Victor >>> >>> -- >>> Victor Forberger >>> [email protected] >>> blog: http://linuxatty.wordpress.com >>> >>> >>> >>> -- >>> xubuntu-users mailing list >>> [email protected] >>> Modify settings or unsubscribe at: >>> https://lists.ubuntu.com/mailman/listinfo/xubuntu-users >> >> > > -- > Sent from my Android device with K-9 Mail. Please excuse my brevity. > > -- > xubuntu-users mailing list > [email protected] > Modify settings or unsubscribe at: > https://lists.ubuntu.com/mailman/listinfo/xubuntu-users > -- xubuntu-users mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/xubuntu-users
