Rainbow – an attempt to display colour on a B&W monitor
The aim of this project was to display a colour image on a black and white monitor, by overlaying an acetate bayer filter over the monitor and mosaicing a colour image.
Classic ThinkPad Thermal Paste Change
Those who know me know that I am a bit fan of the oldschool Lenovo ThinkPad laptops with real 7-row keyboards. I own several *20 models from 2011 including W520, T420s and X220 ones. They still rock when it comes to ‘laptop computing’ and they are dirt cheap on any auction platform. They only got one flaw … that thermal compound on CPU (and sometimes GPU) gets older a lot faster then these laptops.
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Tiny transformer inside: Decapping an isolated power transfer chip
I saw an ad for a tiny chip that provides 5 volts of isolated power: You feed 5 volts in one side, and get 5 volts out the other side. What makes this remarkable is that the two sides can have up to 5000 volts between them. This chip contains a DC-DC converter and a tiny isolation transformer so there’s no direct electrical connection from one side to the other. I was amazed that they could fit all this into a package smaller than your fingernail, so I decided to take a look inside.
TEMPEST@Home - Finding Radio Frequency Side Channels
As the test procedures in the TEMPEST standards are rudely made unavailable to us as they are considered “classified” we have to do the next best thing and make up our own. This article aims to make barely acceptable analogies about how radios work and show that you really don’t need that much in terms of know-how and equipment to find and take advantage of leaky radio signals. Towards the end, we will apply what we have learned to find a signal that can exfiltrate data out of a radio-less and air-gapped desktop workstation through a wall and 50ft away.
Hacking together a USB-C charger for a cheap Chromebook
Only one thing won’t charge with USB-C, my awfully cheap ($190 for 4GB of RAM) Samsung Chromebook 3, a machine I use when I want the extra security of the Chrome OS platform. Instead, this laptop charges from an old-school 12V barrel connector, forcing me to carry around an extra brick.
What we need is called a “USB-C PD trigger”, a little board that negotiates a specific PD voltage with a charger. There are a few variants, including ones with a button to select the voltage, but the most common one is a tiny board with a female USB-C connector called ZYPDS.
The universe's biggest gear reduction
Today at 14:52 I will be exactly 1 billion seconds old. To celebrate I build this machine that visualizes the number googol. That’s a 1 with a hundred zeros. A number that’s bigger than the atoms in the known universe. This machine has a gear reduction of 1 to 10 a hundred times. In order to get the last gear to turn once you’ll need to spin the first one a google amount around. Or better said you’ll need more energy than the entire known universe has to do that. That boggles my mind.
Meet the ZedRipper – a 16-core, 83 MHz Z80 powerhouse as portable as it is impractical. The ZedRipper is my latest attempt to build a fun ‘project’ machine, with a couple of goals in mind:
As part two (see previous attempt) of my ongoing series in ‘computational necromancy,’ I’ve spent the last year and a half or so constructing my own 1/10-scale, binary-compatible, cycle-accurate Cray-1. This project falls purely into the “because I can!” category – I was poking around the internet one day looking for a Cray emulator and came up dry, so I decided to do something about it. Luckily, the Cray-1 hardware reference manual turned out to be useful enough that implementing most of this was pretty straightforward. The Cray-1 is one of those iconic machines that just makes you say “Now that‘s a super computer!” Sure, your iPhone is 10X faster, and it’s completely useless to own one, but admit it . . you really want one, don’t you?
Turning a MacBook into a Touchscreen Using the Webcam
Our idea was to retrofit a small mirror in front of a MacBook’s built-in webcam, so that the webcam would be looking down at the computer screen at a sharp angle. The camera would be able to see fingers hovering over or touching the screen, and we’d be able to translate the video feed into touch events using computer vision.
Extracting BitLocker keys from a TPM
By default, Microsoft BitLocker protected OS drives can be accessed by sniffing the LPC bus, retrieving the volume master key when it’s returned by the TPM, and using the retrieved VMK to decrypt the protected drive. This post will look at extracting the clear-text key from a TPM chip by sniffing the LPC bus, either with a logic analyzer or a cheap FPGA board. This post demonstrates the attack against an HP laptop logic board using a TPM1.2 chip and a Surface Pro 3 using a TPM2.0 chip. From bus wiring through to volume decryption. Source code included.
Building a 10BASE5 “Thick Ethernet” network
Fast forward to 2012, and 10BASE5 is now truly a vintage technology. Anyone studying something I.T. related likely will at some point have been told about this stuff, because it’s very important in the history of computing. This was the first standardised, commercially used form of Ethernet, and today, almost the entire Internet is Ethernet, but heck, who’s ever actually seen a working 10BASE5 setup? Not me, that’s for sure, nor or anyone I’ve ever met.
So… can I build a working setup in 2012? Read on…
For someone like me who hadn’t encountered it before, no amount of looking at pictures could prepare for how big this stuff is. Short of high power transmission cables, it’s the largest coaxial cable I’ve ever seen. It is also very heavy, rigid and the bend radius is absurdly large.
Several Motorola MDT-9100T “Mobile Data Terminals” came up on eBay and their retro-future design was too neat to pass up. The stylish housing combined with an aperture-less amber CRT looks like something slipped from the Fallout or BladeRunner universe into our own. Some of us at NYC Resistor bought them and are repurposing them.
In order to replace the i386 with a BeagleBone Black it was necessary to build an adapter board that plugs into the ribbon cable, deduce the VGA timings and write a Device Tree overlay (DTBO) to configure the LVDS framing for the special screen, and design a USB HID keyboard interface for the keyboard and function keys.
Gigatron TTL microcomputer
The Gigatron TTL microcomputer is a minimalistic retro computer. It is special in its own oddball way, because it has absolutely no complex logic chips in it, not even a microprocessor! Instead, its CPU is built out of a handful of classic 7400-series chips, also known as the TTL logic series. In the Gigatron these simple ICs not only form a CPU, but this CPU in turn also performs tasks that normally need dedicated peripheral chips. Despite its simple and compact design, the Gigatron works as an 8-bit single-board microcomputer that you can play video games with.
Reading hotel key cards with a credit card magstripe reader
In this post I describe how my cheap magstripe reader wouldn’t read all magstripes, only credit/debit cards. This did nothing to help me understand what data was on my hotel key card – which is what I really wanted to know. Rather than take the obvious next step or buying a better reader, I opted to open up the cheap magstripe reader, probed around a bit and found a way to read the raw data off the hotel magstripes.
Making a Window Manager
You could raise from the chair and turn the shades, I guess. You could. But I can not. I need an automatic sun-b-gone mechanism! Something smart, IOT and with blockchain technology. A true Window Manager™.
Breaking the Ledger Security Model
In this post, I’m going to discuss a vulnerability I discovered in Ledger hardware wallets. The vulnerability arose due to Ledger’s use of a custom architecture to work around many of the limitations of their Secure Element.
Implementing FizzBuzz on an FPGA
I recently started FPGA programming and figured it would be fun to use an FPGA to implement the FizzBuzz algorithm. An FPGA (Field-Programmable Gate Array) is an interesting chip that you can program to implement arbitrary digital logic. This lets you build a complex digital circuit without wiring up individual gates and flip flops. It’s like having a custom chip that can be anything from a logic analyzer to a microprocessor to a video generator.
The story of solder, the unsung hero of the digital revolution
Sure, we might talk about the chips inside of that machine, or the processing power, but rarely do we think about the connective tissue holding many of the circuits onto the silicon. That tissue is solder, the meltable filler metal that has existed in one form or another for more than 4,000 years—long before electronics even existed as a modern context.
Xerox Alto's 3 Mb/s Ethernet: Building a gateway with a BeagleBone
The Alto’s 3 Mb/s Ethernet isn’t compatible with modern Ethernet, making it difficult to transfer data between an Alto and the outside world. To solve this, I built a gateway using the BeagleBone single-board computer to communicate with the Alto’s Ethernet. In this article I discuss how the Alto’s Ethernet works and how I implemented the gateway.