Programmatically determine if a display is On or Off

A Just Add Power Receiver keeps track of whether the connected display is powered on or off. Essentially, the Receiver is looking for an active HDMI connection to a display.

Telnet into a Receiver and send this command:

cat /sys/devices/platform/display/monitor_info | grep "attached=y" -c

Responses:

  • 0 = The display is off, or the HDMI cable from the Receiver to the display is disconnected
  • 1 = The display is on.
  • 267
  • 20-Mar-2018
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