Linux E-Readers

[DNSB]

Originally Posted by salamanderjuice

Okay, last time I looked into it, it required modifying system files to even enable telnet. There's not much point to doing it so I stopped caring about the time of the Kobo Mini. I was wrong. Sorry.

You kind of got sidetracked that it was so easy to get root access on a Kobo that you missed the main point of the thread IMO, and that's that eReaders running Linux don't really run Linux in the same way as a Ubuntu install or Fedora.

The CLI is pretty much the same as the first Linux version I ran and I don't have to boot from a couple of floppies to get there. Considering that I now use a CLI to manage most of the Windows and Linux servers I work with, I actually don't spend that much time use a GUI anymore.

[hobnail]

If the OP wants to make something with the advantages of an e-ink display with the advantages of using Linux my thinking is the same as salamanderjuice's; get a Pi (e.g., the Zero W with headers) and connect it to an e-ink display. A google search brought up lots of hits; I started searching for raspberry pi e ink and it had lots of hits for raspberry pi e ink calendar.

But the Pi will need to be connected to power; for a battery powered setup the ESP32 is a common choice. You could use micropython on the ESP32, or C, etc. I don't know if there's code available for using micropython and an e-ink display, but ferreting around on github might yield something.

For a nice case, if there isn't one already available (and you don't have a 3d printer) you could design your own and then work with someone in your area who takes work; e.g. see https://www.prusaprinters.org/world .

[jgneff]

Originally Posted by db579

Ok so can I ssh in and run a command with sudo?

Almost. You can telnet in to a Kobo and run commands directly as root after you enable development mode by searching for "devmodeon".

Do I have bash? GCC?

No, but once you're connect you can install a full Ubuntu or Debian distribution running in chroot jail. At that point, it's like you have an ARMv7-A Raspberry Pi 2 Model B v1.1 running Linux as a server with up to 60,000 software packages available to install.

What is the blocker to running regular software on it?

There are two blockers:

• The Kobo devices use older kernels, so they can run only certain older Linux distributions under chroot.
• Applications write to the e-paper display using an extended version of the Linux framebuffer API rather than X Windows or Wayland.

The first blocker means you're limited to Linux kernel version 2.6.35 on the oldest Kobo models like the Kobo Touch N905B and N905C, version 3.0.35 for the Kobo Glo HD, and version 4.1.15 for the latest models like the Kobo Clara HD. The second blocker means you can't easily run normal Linux desktop applications directly from your Debian or Ubuntu chroot environment.

You can replace the Linux kernel on the device, but that's a lot more work and rather tedious. (I never even tried.) You can write your own e-paper display applications, which is still a lot more work but also a lot of fun.