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Show HN: E-Ink Day Schedule

by dh-g on 9/25/23, 12:31 PM with 129 comments

• by 2bitencryption on 9/25/23, 5:22 PM

  If you're even slightly interested in getting into jailbreaking/hacking of devices, the Kindle is a great place to start.

  There's a lot of low-hanging fruit there. Particularly because the device has a USB port and, by design, exposes a user partition that you can read/write to (so you can upload files and documents and ebooks to the device).

  There's definitely been an effort by Amazon to lock them down, but just taking your reverse-engineering tool of choice and decompiling their firmware binary will give you tons of readable code to dig through. They use a mix of java, native c, and javascript.

  Fun fact, at startup the Kindle looks for certain files in the user partition, with certain naming patterns. You can, for example, disable the screensaver by dropping a file with a special name there. They patched this once, but after doing a grep for the user-partition mount location (to see all the places in their code where they read from user partition files) I was pretty quickly able to find another way to do this. It's fun stuff.

• by omershapira on 9/25/23, 2:37 PM

  The most fun part of these projects is seeing people quickly build ad-hoc renderers for E-Ink. Very quickly you find out you need render passes, dithering, debanding, etc.

  Here's my weather E-Ink board (which consistently gives a faster result than waiting for the iOS weather app to fetch & render): https://github.com/OmerShapira/theres-some-weather-outside

• by Arubis on 9/25/23, 1:49 PM

  If you’re not up for DIY, I’ve been using a unit from https://www.invisible-computers.com/ for years and I love it. Not affiliated; just a happy customer.

• by politelemon on 9/25/23, 1:34 PM

  I repurpose all my old ereaders (Kindles and Kobos) into displays for something, weather, agendas, some even do images (albeit very low resolution). It's great to have these around the house, quietly doing their thing.

  One thing I will point out from observation, the radios on ereader devices aren't great for heavy use; they were originally created for occasional syncing. Projects like these will require an HTTP request to somewhere to fetch data, on a regular basis, and the radio eventually stops working. It's not a terrible thing considering it's just an unused device. If you're looking for something longer lived, the waveshare screen are worth considering for mini projects.

• by blagie on 9/25/23, 3:26 PM

  What I really want is a simply end-to-end way to program these devices to display something: basically, something as easy as QBasic, P5.js, or Scratch.

  What I don't want is to run a server to host something for them to display. I want it self-contained, so once made, it's alive until the device breaks. My experience is 95% of the cost of these is maintenance, and that goes away once a project is no longer new, glitzy, and flashy.

  What I actually want to build myself is a clock which displays time in time zones where my friends, relatives, and family are. Most of the other things I'd like are equally esoteric. I'd like this to be a <3 hour project (so it sustains a child's attention span too).

• by iforgotpassword on 9/25/23, 2:11 PM

  I did something similar with a first gen kindle. Some day it stopped working, I opened the enclosure to find a completely cracked-open kindle with a battery the size of a weather balloon inside.

  This was about a month after I returned from a six week trip during which I kept that thing running.

  Reminder that a lot of battery-powered devices really don't like to be connected to power all the time.

• by afavour on 9/25/23, 1:37 PM

  An aside but I’ve long thought that if Apple was truly committed to the environment and equipment reuse they’d let us use old iPads for stuff like this. I’d love to make a digital photo frame/day planner from an old iPad mini I have kicking around. They could even integrate Siri etc.

  (I know you can get some way toward this with various apps but it’s definitely not the same as something OS-level)

• by 0x38B on 9/25/23, 2:20 PM

  Another option for displaying things on a jailbroken Kindle is to use kterm to ssh into a computer and then connect to a tmux session. I've used this to read man pages - it's quite satisfying to press 'f' on my laptop and see the page scroll on the Kindle.

  Connectivity is easy, as you can connect over USB or WiFi (my Kindle connects to my iPhone's hotspot).

• by demondemidi on 9/25/23, 8:52 PM

  Keep it out of the sun. E-Ink does not like direct sunlight. I built a similar thing, more of central panel for all my home-grown cloud gadgets (because I hate backlit LCD), and after a summer of afternoon sun, half the panel died. Which was a bummer because it was a $300 panel.

• by landgenoot on 9/25/23, 3:49 PM

  Nice project.

  I did something similar, but with photos. I managed to process everything on the device in 100% golang with imagemagick C-bindings.

  As Imagemagick is also able to render text, it might be a solution for you to get rid of the need for an external server. The ARM build process happens on GitHub actions, so you can check it out.

  https://github.com/landgenoot/kindle-synology-photos-photofr...

• by Waterluvian on 9/25/23, 1:27 PM

  The crispness of e-ink is 99% of what makes me want it for semi-static displays. It’s just ridiculously satisfying to look at.

• by stavros on 9/25/23, 3:03 PM

  I did kind of the same thing with a LilyGo display, and it looks amazing:

  https://www.stavros.io/posts/making-the-timeframe/

  I had to turn it into a generic signage platform first (it lets you show any image you want), and then screenshot GCal onto that image. It works really well, though.

  Nowadays it's an electronic power meter, which also looks great.

• by ros86 on 9/25/23, 6:34 PM

  I can recommend checking out https://openepaperlink.de/. It's a project to repurpose e-ink electronic shelf labels (in various sizes, ranging from 1.54" to 7.4"). I have been playing around with it the last few weeks and it's a lot of fun! The community around this is very active on Discord.

• by michaelbuckbee on 9/25/23, 1:09 PM

  I use a Kindle Fire (non E-ink) tablet as a dedicated calendar viewing tool as:

  1. It's very easy to put it into developer mode and set "don't lock screen if plugged in"

  2. I can just open it to a web page of my calendar.

  This is great as I don't get nerd-sniped into some dev project trying to set it all up and actually get a functional calendar so I don't miss things.

• by Neil44 on 9/25/23, 12:55 PM

  That's cool. I regret throwing my ancient kindle away now.

  The expensive corporate version of this is called a Joan - https://getjoan.com/digital-signage/

• by yankput on 9/25/23, 3:11 PM

  I have just bought aranet4, a CO2 meter, which uses eink and I think partly because of that has a ridiculously long 5 year battery life.

  But I understand why… it’s 169eur, the cheaper CO2 meters are just much cheaper.

• by scottwick on 9/25/23, 1:20 PM

  Does this use the battery? Not clear to me if the Kindle program is running continuously or if it just periodically starts up, refreshes the screen and then powers back down.

• by rtpg on 9/25/23, 2:14 PM

  I have done something like this with my kindle. I then got kind of mad at myself for doing something so utilitarian. I wrote a little script to instead generate random wordle playthroughs, display that, be happy with the code... then immediately throw the kindle in my drawer.

  Still, "generate a static image from a computer and send it to a display at a certain rate" is an underrated way to do fun things

• by zephrx1111 on 9/25/23, 2:35 PM

  There are many android eink reader out there the can be used easily for this scenario, why ppl are always bothered on kindle?

• by jwong_ on 9/25/23, 8:29 PM

  Recently went the DIY route to show a Notion board on my 4th gen kindle. This is much nicer though, as it's optimised for display on the lower resolution screen.

  I just wanted to avoid having to pull data out of Notion & re-build a UI. Would be nice for some way to apply CSS to a page to make it more viewable.

• by jncfhnb on 9/25/23, 5:33 PM

  Still dreaming of the day when we can have E Ink Dice

• by giveexamples on 9/26/23, 1:24 AM

  I've been using a magnetic pad (https://www.plus-vision.com/jp/product/kaite/) that works on the same principles of eink, except using magnets rather than electric fields. There's many variants available on aliexpress now. The only con is that stray magnets like on computers will wipe the pad if placed too close together.

• by artursapek on 9/25/23, 12:48 PM

  Very cool. I’d been thinking about building something like this. Do you look at it every day? Seems really useful.

• by kevinwang on 9/26/23, 1:38 PM

  Nice, I literally just started to build something similar on a waveshare and raspi!

• by ThrowawayTestr on 9/26/23, 3:06 AM

  All I want for Christmas is for eink displays to be as cheap as commodity LCDs.

• by polyterative on 9/26/23, 10:58 AM

  I would really buy a generally available ready to hack e-ink display product

• by konschubert on 9/25/23, 2:22 PM

  Hi OP!

  You're writing

  > I use FBInk on the kindle to display the images after curling them from a API Gateway.

  I am the founder of this smart screen product: https://shop.invisible-computers.com/products/invisible-cale...

  Curling an image is the same approach that I use for my e-paper smart screen as well. It should be quite easy to bring your dashboard to my device... maybe we can work together on something? My email is info@invisible-computers.com