@epaperjs/cli

Command line interface for displaying a URL on an ePaper display on a Raspberry Pi

Usage

ejs <command> [options] <deviceType>

For example, the following command will update the Waveshare 7.5" v2 screen with the contents of http://localhost:8080 every 10 minutes.

ejs refresh rpi-7in5-v2 "http://localhost:8080"

For available devices types, see supported hardware. The different commands and suggested workflows are described below.

Commands

Display: display a single rendition of a URL

ejs display [options] <deviceType> <url>

| Option | Description | Allowed Values | | -------------------- | ------------------------------------------------------------------------------------------------------ | --------------------- | | -o / --orientation | Use (h)orizontal or (v)ertical orientation | [h, v] | | -c / --colorMode | Desired color mode | [black, 4gray, red] | | --screenshotDelay | Wait an additional amount of time after loading the URL before displaying. Useful for client side apps | Time in milliseconds | | --dither | Use a dithering algorithm to approximate grayscale / mid-tones on black and white displays | | | --username | Username for basic authentication | username as string | | --password | Password for basic authentication | password as string | | --debug | Print additional log info and stacktraces | | | --version | Show version number | | | --help | Show help | |

Refresh: continuously update and display the URL

ejs refresh [options] <deviceType> <url>

| Option | Description | Allowed Values | | -------------------- | ------------------------------------------------------------------------------------------------------ | -------------------------------- | | -i / --interval | Amount of time between refreshes | Time in seconds (default 10 min) | | -o / --orientation | Use (h)orizontal or (v)ertical orientation | [h, v] | | -c / --colorMode | Desired color mode | [black, 4gray, red] | | --screenshotDelay | Wait an additional amount of time after loading the URL before displaying. Useful for client side apps | Time in milliseconds | | --dither | Use a dithering algorithm to approximate grayscale / mid-tones on black and white displays | | | --username | Username for basic authentication | username as string | | --password | Password for basic authentication | password as string | | --debug | Print additional log info and stacktraces | | | --version | Show version number | | | --help | Show help | |

Clear: clear the display

ejs clear [options] <deviceType>

| Option | Description | Allowed Values | | ----------- | ----------------------------------------- | -------------- | | --debug | Print additional log info and stacktraces | | | --version | Show version number | | | --help | Show help | |

Workflows

Self-Hosting

• Create a web app and store it on your Raspberry Pi
• Host the web app with http-server
• Run ePaper.js with ejs refresh <deviceType> "http://localhost:8080" (or whatever port you configure http-server to run on)

Cloud Hosting

• Create a web app and host it on a service like GitHub Pages or Netlify
• Run ePaper.js with ejs refresh <deviceType> "<URL of your app>"

Running As a Daemon
There are several methods of automatically launching ePaper.js on startup and restarting in case of failures

• Run with pm2
• Create a systemd service

Installation

npm i -g @epaperjs/cli