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DIY Digital Picture Frame

As you may have noticed, Kaddi and I take lots of photos on our vacations. But what good are vacation photos if you never look at them? So when we redecorated the living room recently, we wanted a way to incorporate our pictures as wall decoration. So we were looking to buy a digital picture frame…

We probably ordered every model Amazon has on offer and holy shit are they crap. Not only are they all cheap plastic, they also have horrible resolutions, weird software and sometimes simply not even work. The only decent model we found was the Nix Advance 10 inch. If you want to buy one, get a Nix model.

However even though the Nix 10“ worked fine, we wanted something we could mount to the wall and that looks like an actual frame. So I built it myself.

Last updated: 2018/05/12 13:39 · Permalink · Comments

Hacking an EL-wire Inverter

I recently discovered electroluminescent wire or short EL-wire. It's this cool wire that glows when you apply a current. I had the idea to illuminate our Whiskey cabinet (which really is an old ammunition crate) when you open it.

elwire.jpg I bought a meter of orange wire off eBay for about 7 Euro. EL-Wire requires an inverter that converts DC to AC power. My wire came with a simple one that takes two AA batteries.

Unfortunately that EL driver has a push button that switches through three modes when clicked: on, blinking and off. Since I only need on and off controlled by a DPDT switch, I had to figure out how to hack that onto the controller. Turns out it isn't too hard:

  1. Unscrew the one screw at the back and open the controller
  2. Use a screwdriver to gently push the battery contacts out of the plastic to get access to both sides of the PCB
  3. Flip the PCB upside down and desolder the push button
  4. Add wires through the holes and solder them onto the two contacts on the side of the switch that's closer to the battery (A+B)
    • this overrides the three mode behavior controlled by the microchip under the white blob
    • if you want to keep the three mode behavior but just need a longer trigger cable you can also use the original switch solder points (A+C)
  5. Move the new wires back through the switch hole
  6. Optionally apply some hot glue to the transformer in hope of muffling the high pitched noise a bit
    • didn't have much effect for me
  7. Solder your switch to the other end of the new wires
  8. Reassemble everything

Here are the steps as photos again:

electronics, elwire
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Last updated: 2018/04/09 23:44 · Permalink · Comments

Custom reMarkable Sleeve

The “folio” the reMarkable comes with (if you preorderd) seems to be universally hated for it's low quality and not being very practical either. I wasn't very fond of it myself.

This weekend I tried to make a new sleeve that's more notebook like. I used some purple leather I bought in a store right around the corner. I added some cardboard, glue and a super magnet and made a thing…

Last updated: 2018/02/11 16:10 · Permalink · Comments

File Sync API for reMarkable Tablet

TLDR; I got a new pricy gadget and I wrote some software for it.

I got a new toy: the reMarkable ePaper Tablet.

When I first saw the kickstarter campaign, I immediately wanted it, but I was unsure if they would ever deliver so I didn't back it. I figured when they're successful I can just regularly buy it. It's a decision I regret. Because the reMarkable now retails for 629 EUR while the early preorders started at $379. So expensive! So I tiptoed around the decision to buy one for weeks. In the end I bought one on eBay for about 500 EUR.

The video above gives you a pretty good overview on the pros and cons of the tablet. And before you ask: no, it does not do OCR on your notes.

So why would I buy a very limited device for a price that would buy me a more powerful Android tablet? Because this is what I always wanted. Ever since I saw the very first e-Paper displays. A device that I can just “print” anything to and then scribble on that. A device that feels like paper, but with easy digital archiving and no media breaks. And in that, the reMarkable absolutely delivers.

So what about the software? As the video mentions, there are some kinks in the software on the tablet it self, but the reMarkable people already fixed a few in the update that came out a couple of weeks ago. But what is really good about this tablet is how open it is. It is running Linux, has a running SSH daemon by default and the root password can be accessed from the menu. People already started to write their own software and sharing tips on how to customize the device in a wiki.

One thing nobody had looked at so far, was how the cloud syncing work. As mentioned in the video, the tablet syncs files between itself and the mobile and desktop apps. It's the easiest way to get PDFs on the device. However those desktop apps are somewhat limited.

So I went ahead and tried to figure out how the syncing actually works. Luckily it turns out to be a relatively simple, HTTP and JSON based API. So over the last few days I documented my findings and created a PHP library to talk to the API.

The repository also includes a command line client that can list, download, upload and delete files on the tablet through the sync API.

Eg. the following would copy a PDF from my home directory into the specified folder on the reMarkable.

./remarkable.php ~/mypdf.pdf /work/Projects

The nice thing about using the sync API is that I don't need to be in proximity to the tablet. Eg. right now it's on my desk at the office but I can still easily push documents to it from home.

It would also be easy to integrate pushing documents to the tablet into existing web apps. How about a DokuWiki button that automatically creates a PDF from the current page and puts it on the reMarkable? Or a service that let's you forward emails to your tablet?

I currently have no concrete plans other than using the command line tool, but I do hope my work inspires and helps others to do more awesome things.

remarkable, review, sync, api, php, gadget
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Last updated: 2018/02/02 15:31 · Permalink · Comments

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