Turn the display back on/off on Raspberry Pi

Start by getting access to the GPIO by making a device link

sudo sh -c  "echo 252 > /sys/class/gpio/export"
ls -l /sys/class/gpio

Then turn the display back on with

sudo sh -c  "echo '1' > /sys/class/gpio/gpio252/value"

or back off

sudo sh -c  "echo '0' > /sys/class/gpio/gpio252/value"

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