I think there is a ghost in my house

Hardware
1

Every now and then he/she (the ghost) press right in the middle of my kiosk monitor and brings the energy screen on.

It is driving me completly crazy. I have searched and searched but that behaviour is still hapening at ay time. I cannot say how long. I have sat in front of it 30 minutes but nothing. Some other time it may happen in 5 minutes. I cannot pinpoint where this is comming from. Well… I have my doughts.

Let’s start from the beginning. I replaced an old iPad with a raspberry pi 4 and a touch monitor 10.1 inch about 2 weeks ago. Since then, I have improoved it and many ways. At that point, everything was working just fine. The screen stayed on 24 hours a day. I was about to be 100% satisfied but then I decided to improove it a bit more…

I decided to make the screen turn off at night so the screen would not bother me in my sleep. Yes I see the light from my bedroom. The screen blanking option of the Pi was working fine except I could not find a way to activate and dis-activate it from a command line. I wished to leave it on during daytime, and off at night.

So I found all the info on the web related to xset dpms etc etc. and the “vcgencmd”,“display_power” and all of that stuff. But none of them worked properly as they either don’t wake up on a touch, or even worst, the wake up at the same time that it selects whatever was underneath the press region. Lucky there wasn’t a DELETE ALL command… :wink: Anyway, I removed all of that (I think…).

But every now and then, it selects the center of the monitor. I know that because I replaced the “on tap” of the card that is in the middle of the screen, and the new place was selected.

AI suggested: disable motion/camera (I have none), Switch to panel mode (It’s already in panel mode), Adjust sleep/Screensaver settings (The blanking option in raspi-config is OFF). Also it said to check browser_mod integration: I have no clue what this is.

I also looked at the journalctl. There is an event happening every hour.

> Jan 29 15:17:01 home CRON[2810]: pam_unix(cron:session): session opened for user root(uid=0) by (uid=0)
> Jan 29 15:17:01 home CRON[2811]: (root) CMD (cd / && run-parts --report /etc/cron.hourly)
> Jan 29 15:17:01 home CRON[2810]: pam_unix(cron:session): session closed for user root

But this is happening at every x:17 and even when wahtching it at x:17, I see nothing.

I’m wondering if someone knows what is happening here. Or if someone can tell me how to find out what is triggering this. I see nothing in the HA log related to this. Any idea???

The command I use to start the kiosk mode is:

chromium-browser --noerrdialogs --disable-infobars --kiosk http://homeassistant.local:8123/dashboard-thermostat/thermostat-principal

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2

How is it mounted? I mean in any bracket it might be mounted in, possibly tight and squeezing it slightly?

3

No no… it is hanging. Nothing in that regards. Beside, the mounting has not changed. I’m pretty sure it is something i did related to trying to activate some sort of screen saver. I just cant find whar!

4

Not sure what smart screen you are using. Is it doing smart battery charging, topping it up as required?

Any ants, cockroaches, insects crawling over your screen when the lights are out, homing in on warm spots? Try taping a sheet of cardboard over it overnight to exclude that possibility.

5

Maybe there is something funky in the logic that when it falls asleep or wakes up something in the code causes that button press event to be triggered? Or, if you move the item away from the middle of the screen temporarily for a cople of days does the problem go away, and does the problem come back when you put something else in that spot on the screen that is meant react to presses (and is different code then called)?

6

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Get yourself a P.K.E. meter just to be safe. There is an addon, sorry app for that.

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Don’t bother with the image intensifier as the batteries don’t last very long.

3 Likes
7

Also, did it get slimed?

1 Like
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I had this sudden drop in temp yesterday in my house. Could be a ghost. Again could just be batteries.

9

I actually changed the navigation from the middle button, and the problem showed the new destination. I did not try to remove the middle button. But the testing takes time. For example, it’s has been 4 hours now without the problem.

10

That would tend to indicate the problem is probably software or configuration rather than physical.
Having said that, I hope it is not a manufacturing poor solder joint or internal cable connector that is heat or moisture related. They are the hardest to isolate.
Keep clutching the rosary beads but cancel the priest appointment.

11

I commiserate, having my own ghost which decided to erase an EsP-12F. I think mine was living in a loose contact.

check to see if your power supply is adequate for your RPi/display. Sometimes software causes the CPU usage to spike which could cause a glitch (grasping at straws there)

Who ya gonna call?

12

Lol ok cancelled!

That could very well be. But if I cannot find a solution, I’ll reinstall the pi entirely. Actually, it’s not that hard to do, I only need chromium. The hardest part is to reach the sd card. I have to put the whole thing apart.

Thanks for the tip!

13

Check the logs first, closely,. No screwdriver (or wooden spike) required.

14

What log? As I mentionned, I found nothing in journalctl of the pi, and found nothing either in the log of HA. Do you know something I should know?

15

System log, DNS log, debug log for debug mode for integrations. You are looking for errors and warnings, or just triggers that are unexpected.

16

Anything that could lead me to find out thr problem. For instance, I wish I could find out the exact time this button was pressed. That would be a start. If I can find the unexpected, that would be even better.

17

The raspi is simply running the cron hurly scheduled tasks

Look in /etc/……/cron.hourly folder

It is harmless

18

Yes, I see. Thanks.