5

NOTE: This issue has since been fixed, as far as I am aware (it works now). If you are seeing something else happen, this may not be it. That does, of course, assume that you haven't edited the config in a way that disables this behavior.

In the past, the Raspberry Pi computers could be made to turn off the monitor (as opposed to leaving the backlight on with a blank/black screen) when the Pi turned the screen off on inactivity. This could be done by placing the (poorly documented?) line hdmi_blanking=1 in /boot/config.txt, but this no longer works. I now cannot even find any reference to this command via Google search OR by looking at the RPI references on their site, and it has no effect on my Raspberry Pi 4 -- the screen goes blank, but remains on.

I have had no success even finding someone else asking this question, or determining what method to use to fix it. It does not help that there are many similar answers for different OS and Pi versions that no longer apply...

Has this been replaced by another command, or is it not implemented yet (in the 4's drivers, or the new open-source stack)? I have not checked whether it still works on older Pis, so I can't say whether it's 4-only.

3
  • 2
    Github tracker: github.com/raspberrypi/linux/issues/3050
    – Tom
    Aug 27, 2019 at 21:10
  • 2
    According to this bug report, the latest firmware now supports turning off the backlight - at least for the vcgencmd display_power 0 method. Run sudo rpi-update to get it working now, or wait until the firmware is declared stable, and then an apt update and upgrade will update it.
    – Botspot
    Sep 23, 2019 at 23:39
  • ...That's not good news. Since I just got my 1000-view achievement, something tells me it hasn't been fixed!
    – user50441
    Feb 12, 2020 at 19:08

1 Answer 1

4

I actually just found out the answer -- it's somehow not yet implemented on the Raspberry Pi 4. The command still works on all previous Raspberry Pi devices. Since it seems to be rather difficult to find the page that even mentions this command, I'll link it as follows: Video Options in config.txt

If anyone has comments on why it wouldn't be implemented yet, though, please let me know more. I wasn't aware that the changes would be so large that it would make this not work yet. I'm especially interested in how it will be implemented -- is it a kernel, bootloader, API, or EEPROM change?

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.