aneira92
Posts: 1
Joined: Wed Nov 07, 2018 7:24 pm

Turn on the screen when the raspberry is on

Wed Nov 07, 2018 8:14 pm

I have a raspberry with the touch screen and when I disconnect the power of the screen goes off (it is expected), but when the power is turned on again, it does not turn on. It only turns on when you turn on raspberry and screen at the same time.

I need to be able to turn the screen on and off without needing to restart the raspberry

6by9
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
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Re: Turn on the screen when the raspberry is on

Thu Nov 08, 2018 10:19 am

aneira92 wrote:
Wed Nov 07, 2018 8:14 pm
I have a raspberry with the touch screen and when I disconnect the power of the screen goes off (it is expected), but when the power is turned on again, it does not turn on. It only turns on when you turn on raspberry and screen at the same time.

I need to be able to turn the screen on and off without needing to restart the raspberry
The screen is not designed to be hot-pluggable or switched independently of the Pi. It requires a startup sequence to be sent to it by the Pi, and that only happens during boot

You can control the backlight (which is most of the power consumption) from the Pi.

Code: Select all

echo 0 > /sys/class/backlight/rpi_backlight/brightness
0 is the brightness value in this example. Values between 0 (off) and 255 (max brightness) are permitted. It may need to be run as root.
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
I'm not interested in doing contracts for bespoke functionality - please don't ask.

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