@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