Steady Hand Repurposes Cheap SSD Modules

November 8, 2018 by 52 Comments

For hackers, cheap (and arguably disposable) consumer hardware makes for a ready supply of free or low-cost components. When you can walk into a big box store and pick up a new low-end laptop for $150, how many are going to spend the money to repair or upgrade the one they have now? So the old ones go to the bin, or get sold online for parts. From an ecological standpoint our disposable society is terrible, but at least we get some tech bargains out of the deal.

Case in point, the dirt cheap 32 GB eMMC SSDs [Jason Gin] recently scored. Used by Hewlett Packard on their line of budget laptops, he was able to snap up some of these custom drives for only $12 each. Only problem was, since they were designed for a very specific market and use case, they aren’t exactly the kind of thing you can just slap in your computer’s drive bay. He had to do some reverse engineering to figure out how to talk to them, and then some impressive fine-pitch soldering to get them plugged in, but in the end he got some very handy drives for an exceptionally low price.

[Jason] starts by figuring out the drive’s pinout using the cornerstone of the hacker’s electronic toolkit: the multimeter. By putting one lead on an obvious ground point such as the PCB’s screw holes, you can work through the pins on the connector and make some educated guesses as to what’s what. Ground pins will read as a short, but the meter should read power and data pins as a forward-biased diode. With a rough idea of the pin’s identities and some luck, he was able to figure out that it was basically a standard SATA connection in a different form factor.

To actually hook it up to his computer, he pulled the PCB off of a dead SATA hard drive, cut it down to size, and was able to use fine magnet wire to attach the conductors in the drive’s ribbon cable to the appropriate pads. He sealed everything up with a healthy dose of hot glue to make sure it didn’t pull loose, and then ran some drive diagnostics on his cobbled together SSD to make sure it was behaving properly. [Jason] reports the drive isn’t exactly a speed demon, but given the low cost and decent performance he still thinks it’s worth the work to use them for testing out different operating systems and the like.

[Jason] seems to have something of an obsession with eMMC hacking. Last time we heard from him, he was bringing a cheap Windows tablet back from the dead by replacing its shot eMMC chip.

Put An ItsyBitsy Zork In Your Pocket

November 8, 2018 by 19 Comments

Before computer games had all these fancy graphics, text based games were a very popular genre. Rather than move a character on the screen, you’d type out commands for your player in sentence form which the game would interpret; decades before the “cloud” language processing technology that the likes of Amazon and Google currently use to power their virtual assistants. In some ways the genre was ahead of its time, but it didn’t survive the graphical revolution for home computers. Of course, these games still have some diehard fans out there.

[Dan The Geek] is one such fan. He loves text based adventure games like Zork so much that he wanted to create his own implementation of the core technology that made these games possible all those years ago. But he didn’t want to just do it on this desktop computer, there’s already projects that let you run these classic games on modern hardware. He wanted to see if he could run these classic games on a modern microcontroller, and create a authentic retro experience on a handy portable device.

[Dan] starts by explaining the technology used to make titles like these possible in the days when the wide array of home computer types required a nuanced approach. By separating the story files from the actual interpreter, developers could more easily port the games to various computers. In theory these interpreters, known as “Z-machines”, could be written for any computer that could compile C code, had enough RAM to hold the story, and had a terminal and keyboard. Not exactly the kind of system requirements we’re used to seeing for modern PC games, but it was the 1980’s.

In theory a modern microcontroller will meet these requirements, so [Dan] wanted to create his own Z-machine for one. But rather than “cheat” by using an SD card like previous Arduino Z-machines have, he wanted to see if there was a development board out there that could do it all internally. The answer came in the form of the  Adafruit ItsyBitsy M4 Express, with its 192 kB of RAM and 2 MB of SPI flash.

The Z-machine created by [Dan], which he’s calling A2Z, allows users to run Zork and other compatible interactive text games on the ItsyBitsy without any additional hardware. Just plug the board into your computer and you’ll be able to play the games over the the serial connection. He’s even implemented some retro color schemes to make the experience more authentic, like the blue of the Amiga or Compaq green.

We’ve covered previous projects that brought Zork and friends to the Arduino, your web browser via a virtual Altair 8800, and even some more exotic targets like custom FPGAs. You can play cave adventure, the game that inspired Zork, on the Supercon Badge.

Debugging Arduino Is Painful: This Can Help

November 7, 2018 by 27 Comments

If you are used to coding with almost any modern tool except the Arduino IDE, you are probably accustomed to having on-chip debugging. Sometimes having that visibility inside the code makes all the difference for squashing bugs. But for the Arduino, most of us resort to just printing print statements in our code to observe behavior. When the code works, we take the print statements out. [JoaoLopesF] wanted something better. So he created an Arduino library and a desktop application that lets you have a little better window into your program’s execution.

To be honest, it isn’t really a debugger in the way you normally think of it. But it does offer several nice features. The most rudimentary is to provide levels of messaging so you can filter out messages you don’t care about. This is sort of like a server’s log severity system. Some messages are warnings and some are informational, and some are verbose. You can select what messages to see.

In addition, the library timestamps the messages so you can tell how much time elapsed between messages and what function you were in during the message. It can also examine and set global variables that you preconfigure and set watches on variables. It is also possible to call functions from the serial monitor.

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Printed Parts Turn Ruler Into Marking Gauge

November 7, 2018 by 19 Comments

For Hackaday readers who spend more time with a soldering iron than a saw, a marking gauge is a tool used to put parallel lines on a piece of wood (and occasionally metal or plastic) for cutting. The tool is run across the edge of the piece to be marked, and an adjustment allows the user to set how far in the line will be made. As an example, if you wanted to cut a board into smaller strips, a marking gauge would be an ideal choice for laying out your lines ahead of time.

But as with many niche tools, it’s not something you’re going to use every day. For [chaosbc], this meant he wanted to see if he could come up with a DIY solution on the cheap. Plus he could have it in hand now, rather than waiting for it to take the slow boat from overseas. With the addition of a few clever 3D printed components, he was able to turn his trusty aluminum ruler into a serviceable marking gauge for the cost of filament and a few bits of hardware.

The general design of a marking gauge is fairly simple: there’s a block that rides up and down a graduated shaft (known as the headstock) which allows you to set the depth of the line, and then a piece on the end which holds your marking tool. The marking tool could be a blade if you’re working with something soft enough, but for wood is usually going to be a pencil.

[chaosbc] provides all the STL files for his DIY marking gauge, though they might need adapting as they were created for his specific ruler. Luckily the parts aren’t that complex so it shouldn’t be too difficult to get it sorted out. He also has a useful hint for anyone looking to duplicate his work: a few drops of super glue on the bolt used to lock down the headstock is enough to create a non-marring surface so you don’t tear up your ruler.

We’ve got a few other tips for woodworking on a budget, as well as a primer about this whole making stuff with dead trees concept.

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Junkbox Constant Current Source Helps With Kelvin Sensing

November 7, 2018 by 3 Comments

Is it ironic when a YouTube channel named “The Current Source” needs to build a current source? Or is that not ironic and actually just coincidental?

Regardless of linguistic considerations, [Derek], proprietor of the aforementioned channel has made and disassembled a few current sources in his day. Most of those jobs were for one-off precision measurements or even to drive a string of LEDs in what he describes as a pair of migraine-inducing glasses. Thankfully, The junk box current source presented in the video below is more in service of the former than the latter, as his goal is to measure very small resistances in semiconductors using Kelvin clips.

The current source uses a 24-volt switch-mode power supply and the popular LM317 adjustable voltage regulator. The ‘317 can be configured in a constant current mode by connecting the chip’s adjustment pin to the output through a series resistance. A multiturn pot provides current adjustment, although the logarithmic taper is not exactly optimal for the application. We spotted a pair of what appear to be optoisolators in the build too, but there’s no schematic and no discussion of what they do. [Derek] puts the final product to use for a Kelvin measurement of a 0.47-Ω 1% resistor at the end of the video.

We’re glad to see [Derek] in action; you may recall his earlier video about measuring his own radiation with a Geiger counter after treatment for thyroid cancer. Here’s hoping that’s behind him now.

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Teardown Of A (Relatively) Cheap Thermal Camera

November 7, 2018 by 32 Comments

The cost of tools and test equipment has largely been on the downward trend for years, making it now more affordable than ever to get into the hacking and making scene. This is particularly visible with something like the venerable oscilloscope: a piece of equipment that was near unobtainium for the home hacker a decade ago, you can now get digital pocket scope for as little as $20 USD. But there are still pieces of gear which haven’t quite hit the sort of prices we’d like to see.

A perfect example are thermal imaging cameras. The cheap ones are usually so low resolution they might as well just be thermometers, but the higher resolution ones can cost thousands. [Rob Scott] recently wrote in to tell us about a very promising middle ground, the HTI HT-A1. But he didn’t just point it out to us, he also tore it down and laid its internal’s bare for our entertainment. Now that’s our kind of introduction.

[Rob] walks us through the disassembly of the device, which is made unnecessarily difficult due to the fact that half the screws are hidden under a glued on screen bezel. That means a heat gun, a thin tool, and patience are in order if you want to get inside the device. It’s bad enough they use these kinds of construction techniques on modern smartphones, but at least they’re so thin that we can understand the reasoning. Why this chunky thing needs to resort to such measures is beyond us.

Eventually he cracks the HT-A1 open and is greeted with a single double-sided PCB. The top side is pretty much bare except for the buttons and the LCD display, and the flip side is largely just a breakout for a quad-core Allwinner A33 daughterboard. [Rob] theorizes this is to keep costs down by allowing reuse of the modular A33 board on other devices. Given the A33’s use in so many cheap tablets, it’s also possible HTI simply purchased these daughterboards as a drop-in component and designed their own board around it.

There’s not much else inside the HT-A1 beyond the rechargeable battery pack and thermal camera, both attached to the device’s rear panel. [Rob] noticed that the date on the thermal camera PCB is a full two years older than the date on the main PCB, leading one to wonder if HTI might have gotten a good deal on a bunch of these slightly outdated sensors and spun up a whole device around them.

The HT-A1 is high enough resolution that you can actually pick out individual components on a PCB, and at $400 USD is approaching a reasonable price point for the individual hacker. Which is not to say it’s cheap, but at least you get a useful tool for your money. We wouldn’t suggest you buy this device on a whim, but if you do a lot of diagnostic work, it might pay for itself after a couple repairs.

If that’s still a little too rich for your blood, we’ve covered a handful of DIY options which might better fit your budget.

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Rooting The Amazon Fire TV Cube With An Arduino

November 7, 2018 by 11 Comments

Amazon might not be happy about it, but at least part of the success of their Fire TV Stick was due to the large hacking and modification scene that cropped up around the Android-powered device. A quick search on YouTube for “Fire Stick Hack” will bring up a seemingly endless array of videos, some with millions of views, which will show viewers how to install unofficial software on the little media dongle. Now it looks like their latest media device, the Fire TV Cube, is starting to attract the same kind of attention.

The team at [Exploitee.rs] has recently taken the wraps off their research which shows the new Fire TV Cube can be rooted with nothing more than an Arduino and an HDMI cable you’re willing to cut apart. Of course, it’s a bit more complicated than just that, but between the video they’ve provided and their WiKi, it looks like all the information is out there for anyone who wants to crack open their own Cube. Just don’t be surprised if it puts you on the Amazon Naughty List.

The process starts by putting the device’s Amlogic S905Z into Device Firmware Upgrade (DFU) mode, which is done by sending the string “boot@USB” to the board over the HDMI port’s I2C interface. That’s where the HDMI cable comes in: you can cut into one and wire it right up to your Arduino and run the sketch [Exploitee.rs] has provided to send the appropriate command. Of course, if you want to get fancy, you could use an HDMI breakout board instead.

With the board in DFU mode in you gain read and write access to the device’s eMMC flash, but that doesn’t exactly get you in because there’s still secure boot to contend with. But as these things tend to go, the team was able to identify a second exploit which could be used in conjunction with DFU mode to trick the device into disabling signature verification. Now with the ability to run unsigned code on the Fire TV Cube, [Exploitee.rs] implemented fastboot to make it easier to flash their custom rooted firmware images to the hardware.

As with the Fire TV Stick before it, make sure you understand the risks involved when you switch off a device’s security features. They’re often there to protect the end user as much as the manufacturer.

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