Ask Hackaday: A Robot’s Black Market Shopping Spree

It was bad when kids first started running up cell phone bills with excessive text messaging. Now we’re living in an age where our robots can go off and binge shop on the Silk Road with our hard earned bitcoins. What’s this world coming to? (_sarcasm;)

For their project ‘Random Darknet Shopper’, Swiss artists [Carmen Weisskopf] and [Domagoj Smoljo] developed a computer program that was given 100 dollars in bitcoins and granted permission to lurk on the dark inter-ether and make purchases at its own digression. Once a week, the AI would carrying out a transaction and have the spoils sent back home to its parents in Switzerland. As the random items trickled in, they were photographed and put on display as part of their exhibition, ‘The Darknet. From Memes to Onionland’ at Kunst Halle St. Gallen. The trove of random purchases they received aren’t all illegal, but they will all most definitely get you thinking… which is the point of course. They include everything from a benign Lord of the Rings audio book collection to a knock-off Hungarian passport, as well as the things you’d expect from the black market, like baggies of ecstasy and a stolen Visa credit card. The project is meant to question current sanctions on trade and investigate the world’s reaction to those limitations. In spite of dabbling in a world of questionable ethics and hazy legitimacy, the artists note that of all the purchases made, not a single one of them turned out to be a scam.

Though [Weisskopf] and [Smoljo] aren’t worried about being persecuted for illegal activity, as Swiss law protects their right to freely express ideas publicly through art, the implications behind their exhibition did raise some questions along those lines. If your robot goes out and buys a bounty of crack on its own accord and then gives it to its owner, who is liable for having purchased the crack?

If a collection of code (we’ll loosely use the term AI here) is autonomous, acting independent of its creator’s control, should the creator still be held accountable for their creation’s intent? If the answer is ‘no’ and the AI is responsible for the repercussions, then we’re entering a time when its necessary to address AI as separate liable entities. However, if you can blame something on an AI, this suggests that it in some way has rights…

Before I get ahead of myself though, this whole notion circulates around the idea of intent. Can we assign an artificial form of life with the capacity to have intent?

Turning the DEFCON Badge Into a Bitcoin Miner


The DEFCON badge this year was an impressive piece of hardware, complete with mind-bending puzzles, cap sense buttons, LEDs, and of course a Parallax Propeller. [mike] thought a chip as cool as the Propeller should be put to better use than just sitting around until next year so he turned it into a Bitcoin miner, netting him an astonishing 40 hashes per second.

Mining Bitcoins on hardware that doesn’t have much processing power to begin with (at least compared to the FPGAs and ASIC miners commonly used) meant [mike] would have to find some interesting ways to compute the SHA256 hashes that mining requires. He turned to RetroMiner, the Bitcoin miner made for an original Nintendo. Like the NES miner, [mike] is offloading the communication with the Bitcoin network to a host computer, but all of the actual math is handled by a single core on the Propeller.

Saving one core for communication with the host computer, a DEFCON badge could conceivably manage 280 hashes/second, meaning the processing power of all the badges made for DEFCON is about equal to a seven-year-old graphics card.

Mining Bitcoins with Pencil and Paper

Right now there are thousands of computers connected to the Internet, dutifully calculating SHA-256 hashes and sending their results to other peers on the Bitcoin network. There’s a tremendous amount of computing power in this network, but [Ken] is doing it with a pencil and paper. Doing the math by hand isn’t exactly hard, but it does take an extraordinary amount of time; [Ken] can calculate about two-thirds of a hash per day.

The SHA-256 hash function used for Bitcoin isn’t really that hard to work out by hand. The problem, though, is that it takes a 64 byte value, sends it through an algorithm, and repeats that sixty-four times. There are a few 32-bit additions, but the rest of the work is just choosing the majority value in a set of three bits, rotating bits, and performing a mod 2.

Completing one round of a SHA-256 hash took [Ken] sixteen minutes and forty-five seconds. There are sixty-four steps in calculating the hash, this means a single hash would take about 18 hours to complete. Since Bitcoin uses a double SHA-256 algorithm, doing the calculations on a complete bitcoin block and submitting them to the network manually would take the better part of two days. If you’re only doing this as your daily 9-5, this is an entire weeks worth of work.

Just for fun, [Ken] tried to figure out how energy-efficient the bitcoin mining rig stored in his skull is. He can’t live on electricity, but donuts are a cheap source of calories, at about $0.23 per 200 kcalories. Assuming a metabolic rate of 1500 kcal/day, this means his energy cost is about 67 quadrillion times that of an ASIC miner.

Video below.

Continue reading “Mining Bitcoins with Pencil and Paper”

Hackaday Links: July 20, 2014


Etch-a-Sketch spray-painted silver with electronics bolted onto the side? Sign us up! This art installation adds one thing that we don’t often see in these types of hacks, eerie audio.

If you’re still mining bitcoin you need to do it faster than anyone else… that’s pretty much how the whole thing works. [Lewin] has been using the Antminer USB ASIC and toyed around with overclocking to 2.2 GH/s (gighashes per second) but to make sure his hardware holds up to the overwork he hacked his own water cooling system for the dongle.

Smart phones are the best bang for your buck on portability and power. Better yet you can get slightly broken ones for a song. If you manage to find an Android device with a broken touch screen but functioning LCD try this trick to add a mouse to it. There must be another life for this in a future hack!

We have a love-hate relationship with this particular crowd-funding campaign. First this hate: It’s basically a 100% clip-art video presentation with an $800,000 ask. Yeah… good luck buddy. On the other hand, this is the type of stuff we actually want to see as crowd funding. The idea is to use modern materials and techniques to build [Nikola Tesla’s] Wardenclyffe Tower, which was designed and built to research wireless energy (both as a means of communication and actual energy transfer). It was never fully functional and ended up being demolished. Wouldn’t it be great if teams of highly skilled and motivated people took grand ideas like this, crossing every theoretical “t” and dotting every theoretical “i”, and then proposed a crowd funding campaign to build a test platform? Oh wait, that sounds very much like a government research grant. Anywhoo… check out the Global Energy Transmission’s campaign.

Never Miss a Thing With This Programmable Vacuum Fluorescent Display Ticker

VFD Ticker

[Coyt] wanted a more convenient way to keep up to date with the ever-changing Bitcoin exchange rates, as well as weather and other useful information. He realized that the vacuum fluorescent display (VFD) he had purchased a couple of years ago would be perfect to display small amounts of information.

[Coyt] discovered that the VFD had a serial interface. The problem was that the VFD was looking for a 12V serial signal but the Raspberry Pi he wanted to use runs at a 3.3V. Upon closer inspection [Coyt] discovered that the VFD actually ran at lower levels as well, but it had a level converter chip installed in front of the main connector. He simply bypassed the level converter and was then able to get the RasPi speaking directly to the VFD.

The brain running this display is a Raspberry Pi. The Pi runs a Python script that pulls down all of the relevant information from the internet and displays it on the VFD. [Coyt] didn’t stop there, though. He knew that having the screen on all of the time would be somewhat of a waste, so he hooked up a PIR sensor to automatically turn on the display only when needed. The PIR sensor can detect motion in the room and will disable the display after a set period of inactivity. Most of this is powered by an LM7805 voltage regulator. While [Coyt] admits a linear regulator is not his ideal solution, it does get the job done. The metal stand acts as a nice heat sink for the regulator.

[Coyt] also wanted his project to have a certain aesthetic. He started by bending a metal plate into a stand for the electronics. He then mounted the VFD on the front of the stand and the RasPi on the back. He also mounted green LEDs between the two plates to light up the edges for a little extra pizzazz. [Coyt] believes he can use the RasPi to PWM the LEDs but this has not yet been implemented. This would allow him to pulse the light for added effect.

Since the whole thing is run by a Python script, it would be trivial to modify it to display other kinds of information. What would you do if you had a motion sensitive automatic ticker?


Sniffing Vending Machine Buses

Sniffing the Multidrop Bus


We’ve talked about a variety of protocols and how to deal with them in the past. Today, [Dan] is working on sniffing vending machine Multidrop Bus. The Multidrop Bus (MDB) protocol is a standard used in vending machines to connect devices such as currency collectors to the host controller.

To connect to the bus, interface hardware is required. [Dan] worked out compliant hardware and connected it to an Arduino. With the device on the bus, [Dan] got to work on an Arduino sketch to parse the MDB data into a human-readable format. With that working, the bus can easily be sniffed over the Arduino’s serial console.

This is just the start of a more involved project. Since this protocol is used to communicate with a vending machine’s currency collector or card reader, being able to communicate it would allow him to implement his own payment methods. The plan is to augment the vending machine he operates at Vancouver Hack Space to accept Bitcoin. We’re looking forward to seeing that project unfold.

Using Bitcoin To Detect Malware


Now that you can actually buy things with bitcoins, it’s become a playground for modern malware authors. [Eric] recently lost about 5 BTC because of some malware he installed and decided to do something about it. He came up with BitcoinVigil, a web service that constantly looks at bitcoin honeypots and alerts you when bitcoins are surreptitiously removed.

The idea behind BitcoinVigil is to set up a Bitcoin wallet with a small amount of coins in it – only about $10 USD worth. When modern, Bitcoin-seeking malware is run on a computer, it looks for this ‘moneypot’ and sends an email out notifying the owner of the coins to stolen money.

[Eric] was at a LAN party a few weeks ago and ‘borrowed’ a friend’s copy of Starcraft 1. Just a few seconds after installing it, he received an alert notifying him about a few stolen bitcoins. This time [Eric] only lost a few microBTC, but better than the thousands of USD he lost before.