Hacking The FPGA Control Board From A Bitcoin Miner

November 18, 2020 by Tom Nardi 49 Comments

For anyone serious about mining cryptocurrency such as Bitcoin, we’re well past the point where a standard desktop computer is of much use. While an array of high-end GPUs is still viable for some currencies, the real heavy hitters are using custom mining hardware that makes use of application-specific integrated circuits (ASICs) to crunch the numbers. But eventually even the most powerful mining farm will start to show its age, and many end up selling on the second hand market for pennies on the dollar.

Naturally, hackers are hard at work trying to find alternate uses for these computational powerhouses. While it won’t teach an old ASIC a new trick, [xjtuecho] has documented some very interesting details on the FPGA control board of the Ebit E9+ Bitcoin miner. Known as the EBAZ4205, this board can be purchased for around $20 USD from online importers and even less if you can find one used. Since it’s just the controller it won’t help you build a budget super computer, but there’s always interest in cheap FPGA development boards.

The Zynq SoC combines an FPGA and ARM CPU.

According to [xjtuecho], it takes a little bit of work to get the EBAZ4205 ready for experimentation. For one thing, you may have to solder on your own micro SD slot depending on where you got the board from. You’ll also need to add a couple diodes to configure which storage device to boot from and to select where the board pulls power from.

Once you’re done, you’ll have a dual core Cortex A9 Linux board with 256 MB DDR3 and a Artix-7 FPGA featuring 28K logic elements to play with. Where you go from there is up to you.

This isn’t the first time we’ve seen FPGA boards hit the surplus market at rock bottom prices. When IT departments started dumping their stock of Pano Logic thin clients back in 2013, a whole community of dedicated FPGA hackers sprouted up around it. We’re not sure the if the EBAZ4205 will enjoy the same kind of popularity in its second life, but the price is certainly right.

[Thanks to Rog77 for the tip.]

Exploring The New Super Mario Game & Watch

November 17, 2020 by Tom Nardi 26 Comments

Nintendo has revived the classic Game & Watch, this time in glorious full-color and running the same Super Mario Bros that first graced the Nintendo Entertainment System (NES) back in 1985. Even though it’s only been on the market for a few days, [stacksmashing] has already made some impressive progress towards unlocking the full potential of this $50 retro handheld.

It will come as no surprise to the average Hackaday reader that what we’re looking at here is a pocket-sized NES emulator, but until [stacksmashing] cracked his open, nobody was quite sure what kind of hardware is was running on. Thankfully there wasn’t an epoxy blob in sight, and all of the chips were easily identifiable. Armed with the knowledge that the Game & Watch is running on a STM32H7B0 microcontroller with a nearby SPI flash chip holding the firmware, it was just a matter of figuring out how the software worked.

It didn’t take long to find that an unpopulated header on the board would give him access to the Serial Wire Debug (SWD) interface of the STM32, though unfortunately he found that the chip’s security mode was enabled and he couldn’t dump the firmware.

But he was able to dump the RAM through SWD, which allowed him to identify where the Super Mario Bros NES ROM lived. By connecting the SPI flash chip to a reader and comparing its contents with what the system had in RAM, [stacksmashing] was able to figure out the XOR encryption scheme and come up with a tool that will allow you to insert a modified ROM into an image that can be successfully flashed to the chip.

So does that mean you can put whatever NES ROM you want on the new Game & Watch? Unfortunately, we’re not quite there yet. The emulator running on the device has a few odd quirks, and it will take some additional coaxing before its ready to run Contra. But we’ve seen enough of these devices get hacked to know that it’s just a matter of time.

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Custom Firmware For Cheap Bluetooth Thermometers

November 17, 2020 by Tom Nardi 52 Comments

The Xiaomi LYWSD03MMC temperature and humidity sensor is ridiculously cheap. If you’re buying a few at a time, you can expect to pay as little as $5 USD a pop for these handy Bluetooth Low Energy environmental sensors. Unfortunately, that low price tag comes with a bit of a catch: you can only read the data with the official Xiaomi smartphone application or by linking it to one of the company’s smart home hubs. Or at least, that used to be the case.

Over the past year, [Aaron Christophel] has been working on a replacement firmware for these Xiomi sensors that unlocks the data so you can use it however you see fit. In addition, it allows the user to tweak various features and settings that were previously unavailable. For example, you can disable the little ASCII-art smiley face that usually shows on the LCD to indicate the relative comfort level of the room.

The new firmware publishes the temperature, humidity, and battery level every minute through a BLE advertisement broadcast. In other words, that means client devices can read data from the sensor without having to be paired. Scraping this data is quite simple, and the GitHub page includes a breakdown of what each byte in the broadcast message means. Avoiding direct connections not only makes it easier to quickly read the values from multiple thermometers, but should keep the device’s CR2032 battery going for longer.

But perhaps the most impressive part of this project is how you get the custom firmware installed. You don’t need to crack the case or solder up a programmer. Just load the flasher page on a computer and browser combo that supports Web Bluetooth (a smartphone is probably the best bet), point it to the MAC address of the thermometer you want to flash, and hit the button. [Aaron] is no stranger to developing user-friendly OTA installers for his firmware projects, but even for him, it’s quite impressive.

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Prusa Mini Gets Custom Heavy Duty Enclosure

November 17, 2020 by Tom Nardi 15 Comments

Still waiting on your Prusa Mini to arrive? Join the club. Between the incredible amount of interest in the inexpensive 3D printer and the COVID-19 pandemic, it can take months for the machine to arrive at your doorstep. But patient makers are finally taking delivery of their new printers, and as such the hacks and modifications are starting to trickle their way in.

First up is this gloriously over-engineered enclosure from [Build Comics]. While PLA and PETG usually print fine with nothing more exotic than a heated bed, trickier materials like ABS work best when the printer is enclosed as it helps maintain a consistent temperature. Plus it keeps any curious hands and paws a safe distance from the hot moving bits, and if things go really pear-shaped, can help contain smoke and flames.

The enclosure is made from welded steel square tube, wood, and fire-retardant fiber board. A hinged polycarbonate cover, taking the form of a four-sided cube, is lowered over the printer with some heavy-duty hinges that look like they were intended for a fence. To keep the cover from slamming back down, [Build Comics] came up with a simple locking mechanism that can easily be operated from the front or side of the enclosure. With the addition of a small temperature and humidity display, the conditions inside the chamber can easily be monitored.

But [Build Comics] didn’t stop there. He also rigged up a relay box that will cut power to the printer should the smoke detector mounted above it trip. While there’s no reason to think the Prusa Mini would suffer the same fate of earlier budget desktop 3D printers, but there’s certainly no harm in taking precautions.

Will you need to build a similar enclosure whenever your Prusa Mini shows up? Maybe not. But if you felt so inclined, at least now you’ve got plenty of images and details that can help you spin up your own solution.

3D Print Your Way To A Modular MIDI Playset

November 16, 2020 by Tom Nardi 6 Comments

Have you ever wanted to experiment with MIDI, but didn’t know where to start? Or perhaps you didn’t think you could afford to properly outfit your digital beat laboratory, especially given the average hacker’s penchant for blinkenlights? Well worry no more, as [Johan von Konow] has unveiled a collection of DIY MIDI devices that anyone with a 3D printer can build on the cheap.

The LEET modular synthesizer is made up of a keyboard, drum pad, chord keyboard, arpeggiator and a step sequencer that plug into your computer and interface with industry standard digital audio workstation (DAW) programs. The down side is that they don’t do anything on their own, but this simplification allowed [Johan] to really streamline the design and bring the cost of the build down to the bare minimum.

Integrated wire channels mean no PCB is required.

You don’t need to build all the components either, especially if you’re just testing the waters. The keyboard is a great starting point, and even if you have to buy all the components new from eBay, [Johan] says it shouldn’t cost you more than $10 USD to build. You just need an Arduino Pro Micro, some tact switches, and a section of WS2812 RGB LED strip. There’s an excellent chance you’ve already got some of that in the parts bin, which will make it even cheaper.

There is one missing element though: the PCB. But not because you have to source it yourself. Like his clever Arduboy clone we covered earlier in the year, the 3D printed bodies for all of the LEET devices have integrated wiring channels that serve as a stand-in for a traditional circuit board. Simply place all your components, push some stiff 0.3 mm diameter wire down into the channels, and solder the ends. It’s a very neat approach, and something we could see becoming more popular as desktop 3D printers become an increasingly common sight in the home workshop.

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Youtube-dl Makes Their Case, Returns To GitHub

November 16, 2020 by Tom Nardi 47 Comments

Last month, the GitHub repository for the popular program youtube-dl was taken down in response to a DMCA takedown notice filed by the Recording Industry Association of America (RIAA). The crux of the RIAA complaint was that the tool could be used to download local copies of music streamed from various platforms, a claim they said was supported by the fact that several copyrighted music files were listed as unit tests in the repository.

While many believed this to be an egregious misrepresentation of what the powerful Python program was really used for, the RIAA’s argument was not completely without merit. As such, GitHub was forced to comply with the DMCA takedown until the situation could be clarified. Today we’re happy to report that has happened, and the youtube-dl repository has officially been reinstated.

Represented by the Electronic Frontier Foundation, the current maintainers of youtube-dl made their case to GitHub’s DMCA agent in a letter this afternoon which explained how the tool worked and directly addressed the issue of copyrighted videos being used as test cases in the source code. They maintain that their program does not circumvent any DRM, and that the exchange between the client and server is the same as it would be if the user had viewed the resource with a web browser. Further, they believe that downloading a few seconds worth of copyrighted material for the purpose of testing the software’s functionality is covered under fair use. Even still, they’ve decided to remove all references to the songs in question to avoid any hint at impropriety.

Having worked closely with the youtube-dl developers during this period, GitHub released their own statement to coincide with the EFF letter. They explained that the nature of the RIAA’s original complaint forced their hand, but that they never believed taking down the repository was the right decision. Specifically, they point out the myriad of legitimate reasons that users might want to maintain local copies of streamed media. While GitHub says they are glad that this situation was resolved quickly, they’ll be making several changes to their internal review process to help prevent further frivolous takedowns. Specifically the company says they will work with technical and legal experts to review the source code in question before escalating any further, and that if there’s any ambiguity as to the validity of the claim, they’ll side with the developers.

The Internet was quick to defend youtube-dl after the takedown, and we’re happy to see that GitHub made good on their promises to work with the developers to quickly get the repository back online. While the nature of open source code meant that the community was never in any real danger of losing this important tool, it’s in everyone’s best interest that development of the project can continue in the open.

Teardown: Recon Sentinel

November 16, 2020 by Tom Nardi 35 Comments

It might be hard to imagine now, but there was a time when the average home had only a single Internet connected device in it. This beige box, known as a “desktop computer” in those olden days, was a hub of information and productivity for the whole family. There was a good chance you might even need to wait for your turn to use it, since it’s not like you had a personal device in your pocket that let you log on from ~~the bathroom~~ whatever room you might be in at the time. Which is just as well, since even if you had broadband back then, you certainly weren’t shooting it around the house with the Magic Internet Beams that we take for granted now.

Things are a lot more complicated today. Your computer(s) are only part of the equation. Now there’s mobile phones and tablets sharing your Internet connection, in addition to whatever smart gadgets you’ve brought into the mix. When your doorbell and half the light bulbs in the house have their own IP address, it takes more than a fresh copy of Norton AntiVirus to keep everything secure.

Which is precisely what Cigent Technology says the Recon Sentinel was designed for. Rather than protecting a single computer or device, this little gadget is advertised as being able to secure your entire network by sniffing out suspicious activity and providing instant notifications when new hardware is connected. According to the official whitepaper, it also runs a honeypot service Cigent calls a “cyber deception engine” and is capable of deploying “Active Defense Countermeasures” to confuse malicious devices that attempt to attack it.

It certainly sounds impressive. But for $149.99 plus an annual subscription fee, it better. If you’re hoping this teardown will tell you if it’s worth springing for the $899.99 Lifetime Subscription package, don’t get too excited. This isn’t a review, we’re only interested in cracking this thing open and seeing what makes it tick.

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