Script to Change the Backlight brightness on the Official Raspberry Pi 7" display.

backlight.sh

#!/bin/bash

level=$1
#echo "level given is $level"

if [ $# != 1 ]; then
echo "USAGE: $0 brightness_level (0 to 255)"
exit 1
fi

if [[ $level -ge 0 && $level -le 255 ]]; then
#echo "level given is $level"
echo $level > /sys/class/backlight/rpi_backlight/brightness
echo "Screen brightness set to $level."
exit 0
else
echo "Brightness level $level is out of range! (0 to 255 only)"
exit 1
fi

line 13 gave me a permission denied
i did a little digging and elevated permissions by changing from this:

echo $level > /sys/class/backlight/rpi_backlight/brightness

to this:

sudo sh -c "echo $level > /sys/class/backlight/rpi_backlight/brightness"

Thank you for all your hardwork and research that went into this project