Raspberry Pi How to turn monitor power on

[Timo]

Hello,

I have a Raspberry Pi B+ running under raspbian.

Usually it is run as a "headless" device.

That is:
- In the morning the Raspberry Pi B+ gets booted and starts
Samba so that other machines can access files
stored on external usb-hard-disks attached to the
Raspberry Pi B+.
- When something needs to be done on the Raspberry Pi B+
itself (e.g., updates, setting new passwords, configuring
Samba), this is done via Windows Remote Desktop and
xrdp or via putty/ssh and the ssh server.

But the Raspberry Pi B+ is also attached via a kvm-switch
to usb-keyboard/mouse and hdmi-monitor.

The Raspberry Pi B+ boots into console mode.

When nothing is typed on the console within let's say 15 mins,
the Raspberry Pi B+ will go into power saving mode which
means that when switching the kvm-switch to Raspberry Pi B+,
the hdmi-monitor will show blackness and the Raspberry Pi B+
will neither react on keystrokes from the keyboard nor react
on mouse-movements.

(After entering power saving mode, the Raspberry Pi B+ is
still accessible from other machines, e.g., via
Windows Remote Desktop/xrdp and via putty/ssh.
Accessing the samba-shares provided by the Raspberry Pi B+
is also not a problem after entering power saving mode.)

Is there a method, e.g., a combination of keystrokes or
the like, for switching power on again via (the kvm-switch's)
keyboard/mouse after the Raspberry Pi B+ has entered
power saving mode?

(I don't like to disable the power-saving features completely
as usually the Raspberry Pi B+ is run as a "headless"
device.)

Sincerely

Timo

[druck]

On 03/05/2015 09:19, Timo wrote:
> (I don't like to disable the power-saving features completely
> as usually the Raspberry Pi B+ is run as a "headless"
> device.)

The power saving mode only saves more than a tiny fraction of a Watt,
the Raspberry Pi will happily work 24/7 driving displays with it turned off.

---druck

[Jeffrey Plum]

Most of your power saving will come from your Monitor's power saving ability. On AC power the Pi itself uses a truly tiny amount of power. The new Pi 2 B uses even less at idle, though it may draw more when working hard, I've read. Awake but idle the best "rest" state for AC Pi's like yours. The Pi's power saving sleep features are mostly for battery based systems.

[Francesco Berti]

Hello Timo,
I suppose that your problem is your kvm-switch. When it detect that there isn't signal from hdmi, probably switch on another input for video and mouse/keyboard. So, what you tyoe un in don't reach your raspberry. If so... no solution!
Try connecting this devices (only mouse and keyboard, not display) directly at raspberry and watch if it's all ok.
Francesco.