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Comment by grepular | Hacker News Reader

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grepular·

I can't see an on/off button

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There are three methods of powering the display.

1) Separate power supply

2) USB link

3) GPIO pins

Yes, it is possible to switch the display off and leave the RPi powered on.

Neither does the Raspberry Pi - the user base is pretty used to halting and pulling the power.

The display driver board backpowers the Pi itself so there is no change of process for existing users there.

There are a lot of use cases where you want a machine to be running constantly but don't want the screen to be on constantly.

I can't put one of these in my bedroom unless I can easily and instantly switch the monitor on/off.

[edit] I have an existing PiTFT which also doesn't have a power button. I can turn it on/off programatically, but still a power button would be highly useful.

[edit2] Can this screen be turned off programatically without turning the Pi off at the same time, if the screen is powering the Pi?

[edit3] Hang on. Is it even possible to turn the screen on/off programatically from the Pi if the Pi is powered separately?

You can by a USB cable with switch on it.

Whilst that would work, it's less than ideal. I'd need to power the monitor and Pi separately at that point. If turning the screen off prevents that pass-through power capability, that is a poorly thought out design.

I've just confirmed with the foundation that the display will be controllable from software but the current Raspbian image doesn't have it yet - this will allow you to turn off the screen and backlight while leaving the Pi running.

So your use case will be possible!

That makes the screen a whole lot more useful to me. I will probably buy one when that happens.

You can make one with the GPIO ports :)

Because this is plug and play

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