MMM-Screendimmer

This is an extension to the MagicMirror project. Change the brightness of your Raspberry Pi 7" display based on solar events.

Installation

Run these commands at the root of your magic mirror install.

cd modules
git clone https://github.com/mjtice/MMM-Screendimmer
cd MMM-Screendimmer
npm install

Typically only root can write to the backlight file. You'll need to allow world-writeable permissions on the file.

sudo vi /etc/udev/rules.d/backlight-permissions.rules

Paste the following.

SUBSYSTEM=="backlight",RUN+="/bin/chmod 666 /sys/class/backlight/%k/brightness /sys/class/backlight/%k/bl_power"

Reload udev rules (or just reboot)

sudo udevadm control --reload-rules

Using the module

To use this module, add the following configuration block to the modules array in the config/config.js file:

{
    module: 'MMM-Screendimmer',
    config: {
        latitude: 34.0000,
        longitude: -75.0000
        // See below for additional configurable options
    }
}

Configuration options

option	type	default	description
morning	int	25	time between dawn and sunriseEnd.
day	int	120	time between sunriseEnd and sunsetStart.
evening	int	90	time between sunsetStart and dusk.
night	int	18	time between dusk and dawn.
path_to_backlight	str	'/sys/class/backlight/rpi_backlight/brightness'	where to write the backlight value.
query_interval	int	30000	how frequently to query for the current solar position.
debug	'bool'	false	debugging flag
latitude	'float'	none	no default, will fail without your latitude/longitude in config.
longitude	'float'	none	no default, will fail without your latitude/longitude in config.