Old Kindle Shows HDMI Video, Eventually

January 8, 2021 by Tom Nardi 17 Comments

Even with the recent price reductions on stand-alone panels, picking up a used Kindle is still arguably the most cost effective way to get your hands on a large electronic paper display. Especially when you consider the Kindle includes a battery, case, and electronics to drive the display. Bending the Kindle software to your whims introduces its own unique challenges of course, but with a little tweaking, an old e-reader can live again as whatever you wish it to be.

Case in point, the OkMonitor project by [Brendan Sleight]. Using a somewhat dizzying combination of software and hardware, he’s figured out a way to turn an older Kindle Paperwhite into a plug-and-play HDMI monitor. Is it a great monitor? Far from it. As the name implies, the best you can hope to get from this solution is an OK monitor. But at least it’s something.

There’s quite a bit going on behind the scenes in OkMonitor, which [Brendan] describes through a slideshow on the project page. But the high-level idea is that a Raspberry Pi 4 with a simple USB HDMI capture device takes the video input and converts it on the fly to a scaled down Kindle-friendly format. The converted video is streamed over WiFi to the jailbroken Kindle with netcat, where it’s displayed by a native video player. In the video after the break you can see that the end result looks pretty impressive, even if there is a considerable delay involved.

Despite the demonstration [Brendan] has put together for OkMonitor, we can’t say we’d watch many films over this setup. But the fact that you can plug any HDMI device into the “base station” and have the video sent out to one or more Kindles is undeniably impressive. It’s definitely worth a close look, even if you just take some of the concepts of this project to get your own Kindle repurposing idea off the ground.

We’ve recently seen some promising progress made towards repurposing large e-paper price tags labels, but it’s hard to imagine such niche devices will ever become cheaper than second hand Kindles. With continued software development, these old e-readers are likely to remain quite popular among hackers.

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Remoticon Video: Basics Of RF Emissions Debugging Workshop

January 8, 2021 by Mike Szczys 5 Comments

These days we’re surrounded by high-speed electronics and it’s no small feat that they can all play nicely in near proximity to each other. We have RF emissions standards to thank, which ensure new products don’t spew forth errant signals that would interfere with the data signals traveling through the ether. It’s long been the stuff of uber-expensive emissions testing labs, and failure to pass can leave you scratching your head. But as Alex Whittimore shows in this workshop from the 2020 Hackaday Remoticon, you can do a lot of RF emissions debugging with simple and inexpensive tools.

Professionally-made probes in several sizes

You can get a surprisingly clear picture of what kind of RF might be coming off of a product by probing it on your own workbench. Considering the cost of the labs performing FCC and other certifications, this is a necessary skill for anyone who is designing a product headed to market — and still damn interesting for everyone else. Here you can see two examples of the probes used in the process. Although one is a pack of professional tools and other is a bit of enameled wire (magnet wire), both are essentially the same: a loop of wire on which a magnetic field will induce a very small current. Add a Low-Noise Amplifier (LNA) and you’ll be up and measuring in no-time.

I really enjoyed how Alex started his demo with “The Right Way^TM” of doing things — using a proper spectrum analyzer to visualize data from the probes. But the real interesting part is “The Hacker Way^TM” which leverages an RTL-SDR dongle and some open-source software to get the same job done. Primarily that means using SDRAngel and QSpectrumAnalyzer which are both included in the DragonOS_LTS which can be run inside of a virtual machine.
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Bare-Metal STM32: Universal, Asynchronous Communication With UARTs

January 8, 2021 by Maya Posch 5 Comments

One of the most basic and also most versatile communication interfaces on an MCU is the UART, or Universal Asynchronous Receiver/Transmitter. Usually found in the form of either a UART or USART, the former allows for pure asynchronous serial communication, whereas the latter adds flow control. When working with MCUs, they’re also one of the most common ways to output debug information.

While somewhat trickier to set up and use than a GPIO peripheral, the U(S)ART of ST’s STM32 families is fairly uncomplicated to use, and immediately provides one with an easy way to communicate in a bi-directional fashion with a device. In this article we’ll see what it takes to get started with basic UART communication on STM32 microcontrollers.

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Hackaday Podcast 100: Arduino Plays CDs, Virtual Reality In The 60s, And Magical Linear Actuators

January 8, 2021 by Mike Szczys 16 Comments

Hackaday editors Elliot Williams and Mike Szczys kick off the first episode of the new year with the best hacks the internet has to offer. There’s a deep dive into water-level sensing using a Christmas tree as an excuse. We ooh and ah over turning a CD-ROM drive into a CD player (miraculous tech of the previous century?). Do you have any use cases for ATtiny oscillator calibration registers? We look in on a hack that makes it dead simple to measure and set their values. The episode finishes up with a discussion of the constantly moving goal posts of virtual reality.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (~65 MB)

Places to follow Hackaday podcasts:

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Solid Oak Arcade Cabinet: When Particle Board Won’t Do

January 8, 2021 by Bryan Cockfield 25 Comments

Having an arcade cabinet of one’s own is a common dream among those who grew up during the video game arcade heyday of the 80s and early 90s. It’s a fairly common build that doesn’t take too much specialized knowledge to build. This cabinet, on the other hand, pulled out all of the stops for the cabinet itself, demonstrating an impressive level of woodworking expertise.

The cabinet enclosure is made with red oak boards, which the creator [Obstreperuss] sawed and planed and then glued together to create the various panels (more details are available on his Imgur album). The Mario artwork on the sides and front aren’t just vinyl stickers, either. He used various hardwoods cut into small squares to create pixel art inlays in the oak faces. After the fancy woodwork was completed, the build was finished out with some USB arcade controllers, a flat-panel screen, and a Raspberry Pi to run the games.

While the internals are pretty standard, we have to commend the incredible quality of the woodworking. It’s an impressive homage to classic arcade machines and we wouldn’t mind a similar one in our own homes. If you’re lacking the woodworking equipment, though, it’s possible to get a refined (yet smaller) arcade cabinet for yourself with a 3D printer instead.

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This Week In Security: Android Bluetooth RCE, Windows VMs, And HTTPS Everywhere

January 8, 2021 by Jonathan Bennett 5 Comments

Android has released it’s monthly round of security updates, and there is one patched bug in particular that’s very serious: CVE-2021-0316. Few further details are available, but a bit of sleuthing finds the code change that fixes this bug.

Fix potential OOB write in libbluetooth Check event id if of register notification command from remote to avoid OOB write.

It’s another Bluetooth issue, quite reminiscent of BleedingTooth on Linux. In fact, in researching this bug, I realized that Google never released their promised deep-dive into Bleedingtooth. Why? This would usually mean that not all the fixes have been rolled out, or that a significant number of installations are unpatched. Either way, the details are withheld until the ramifications of releasing them are minimal. This similar Bluetooth bug in Android *might* be why the BleedingTooth details haven’t yet been released. Regardless, there are some serious vulnerabilities patched this in this Android update, so make sure to watch for the eventual rollout for your device. Continue reading “This Week In Security: Android Bluetooth RCE, Windows VMs, And HTTPS Everywhere” →

FISHBOT Reels Them In So You Don’t Have To

January 8, 2021 by Tom Nardi 9 Comments

Fishing is generally thought of as a relaxing and laid-back activity, but it still requires a certain amount of physical strength and dexterity. This can be a problem for older anglers or those with physical disabilities. To bring back the simple joy of fishing to those who may no longer be able to hold a rod on their own, [Ozz] has been working on the FISHBOT.

The FISHBOT looks like a miniature crane, complete with an electric motor and winch to pull in the line. But there’s a bit more going on here than meets the eye. Anyone who’s tried to land a large fish knows you have to be cautious of snapping the line, so [Ozz] has added a load cell to the system that can tell when its being pulled too tightly. In the future he hopes to make this feature a bit smarter by taking into account additional variables, but for now it should at least keep the more energetic of your quarry from getting away.

[Ozz] is controlling the beefy 400 watt motor with an IBT-2 H-bridge module connected to an Arduino Mega. The electronics can communicate with the user’s smartphone over a HM-10 Bluetooth module, which allows for more advanced features such as gesture controls that utilize the accelerometer in the phone. Long term, it sounds like he hopes to use the microcontroller in conjunction with the load cell to pull off more advanced tricks like weighing the fish and sending the data off to the user’s fishing buddies to show off.

In the past we’ve seen a drone used to get a lure out where the fish are, but catching one and reeling it back in is a very different challenge. It looks like [Ozz] still has some work to do on this project, but so far it seems things are going well. Being able to return a simple pleasure like this to those who thought their fishing days were behind them will surely prove worthy of the effort.

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