paperlike-go

paperlike-go is a Go library and CLI tool to control a Dasung Paperlike HD* (2019) screen.

Installation

Paperlike-go can be installed using the go install command:

sudo GOBIN=/usr/local/bin/ go install github.com/leoluk/paperlike-go/cmd/paperlike-cli@latest

Set up i2c permission for your user

Your local user must be able to write to the monitor's i2c bus.

1. Create a new user group called i2c:

   sudo groupadd i2c
   

2. Add your user to the i2c group:

   sudo usermod -a -G i2c $USER
   

3. Change the group ownership of /dev/i2c codepoints to the i2c group:

   sudo chown :i2c /dev/i2c-*
   

4. Update the group permissions of those same to allow read and write access:

   sudo chmod g+rw /dev/i2c-*
   

5. Create a udev rule to make these changes persistent:

   sudo echo 'KERNEL=="i2c-[0-9]*", GROUP="i2c"' >> /etc/udev/rules.d/10-local_i2c_group.rules
   

Usage:

Usage: paperlike-cli [-i2c <i2c path>] [<command> <value>]

  Optional flags:
        -i2c <path>       absolute path of the target i2c device

  Commands:
        -clear            Clear & refresh screen
        -contrast <1-9>   Set contrast
        -light1 <0-85>    Set light1 intensity; -1 to disable (default)
        -light2 <0-85>    Set light2 intensity; -1 to disable (default)
        -mode <1-4>       Set dithering/display mode
        -speed <1-5>      Set drawing speed

  Examples:
        paperlike-cli -i2c /dev/i2c-3 -mode 1     set the display mode to M1 for the device at /dev/i2c-3
        paperlike-cli -i2c /dev/i2c-5 -clear      clear/refresh the screen for the device at /dev/i2c-5

Manually find the i2c path for your Paperlike device

To determine the i2c path for your device, run the following command:

ddcutil detect --brief | grep -B 1 -Ei "dsc|dasung|paper"

Make note of the I2C bus path (e.g. /dev/i2c-3).

In the case that that this command gives an ambiguous or empty result, you can read the full output by running ddcutil detect --verbose

Display modes:

Refer to your device's manual for the mapping of M1-M4 to specific image modes.

Dasung Paperlike HD (gen 3) Modes

Mode	Name	Goal	Usecases	Notes
1	A2	Emphasize lower latency	Chat applications, real-time dashboards	If ghosting is an issue, make use of the -clear command
2	Floyd	Balance latency and detail	Web browsing, coding, text composition	For best performance, set contrast 3-6.
3	A16	Emphasize fine details	Reading PDFs, calendars, task lists	The Accessibility "Reduce Animations" options in your OS may be useful
4	-	-

Dasung Paperlike HD-F/HD-FT Modes

Mode	Name	Goal	Usecases	Notes
1	A2	Emphasize lower latency	Chat applications, real-time dashboards	If ghosting is an issue, make use of the -clear command
2	Floyd	Balance latency and detail	Web browsing, coding, text composition	For best performance, set contrast 3-6.
3	A61	Emphasize fine details	Images, PDFs, handwriting	The Accessibility "Reduce Animations" options in your OS may be useful
4	-	-

Drawing speeds:

1	Fast++
2	Fast+
3	Fast
4	Black+
5	Black++

Example i3 config:

bindsym $mod+Mod1+1 exec paperlike-cli -i2c /dev/i2c-0 -contrast 1
bindsym $mod+Mod1+2 exec paperlike-cli -i2c /dev/i2c-0 -contrast 2
bindsym $mod+Mod1+3 exec paperlike-cli -i2c /dev/i2c-0 -contrast 3
bindsym $mod+Mod1+4 exec paperlike-cli -i2c /dev/i2c-0 -contrast 4
bindsym $mod+Mod1+5 exec paperlike-cli -i2c /dev/i2c-0 -contrast 5
bindsym $mod+Mod1+6 exec paperlike-cli -i2c /dev/i2c-0 -contrast 6
bindsym $mod+Mod1+7 exec paperlike-cli -i2c /dev/i2c-0 -contrast 7
bindsym $mod+Mod1+8 exec paperlike-cli -i2c /dev/i2c-0 -contrast 8
bindsym $mod+Mod1+9 exec paperlike-cli -i2c /dev/i2c-0 -contrast 9
bindsym $mod+Mod1+h exec paperlike-cli -i2c /dev/i2c-0 -mode 1
bindsym $mod+Mod1+j exec paperlike-cli -i2c /dev/i2c-0 -mode 2
bindsym $mod+Mod1+k exec paperlike-cli -i2c /dev/i2c-0 -mode 3
bindsym $mod+Mod1+l exec paperlike-cli -i2c /dev/i2c-0 -mode 4
bindsym $mod+Mod1+z exec paperlike-cli -i2c /dev/i2c-0 -speed 1
bindsym $mod+Mod1+u exec paperlike-cli -i2c /dev/i2c-0 -speed 2
bindsym $mod+Mod1+i exec paperlike-cli -i2c /dev/i2c-0 -speed 3
bindsym $mod+Mod1+o exec paperlike-cli -i2c /dev/i2c-0 -speed 4
bindsym $mod+Mod1+p exec paperlike-cli -i2c /dev/i2c-0 -speed 5
bindsym $mod+Mod1+Return exec paperlike-cli -i2c /dev/i2c-0 -clear