As most developed countries around the world continue to modernize their transportation infrastructure with passenger rail, countries in North America have been abandoning railroads for over a century now, assuming that just one more lane will finally solve their traffic problems. Essentially the only upside to the abandonment of railroads has been that it’s possible to build some unique vehicles to explore these tracks and the beautiful yet desolate areas they reach, and [Cam Engineering] is using an ebike to do that along the coast of central California.
Photoplotting PCBs With A 3D Printer
Do you ever wonder why your PCB maker uses Gerber files? It doesn’t have to do with baby food. Gerber was the company that introduced photoplotting. Early machines used a xenon bulb to project shapes from an aperture to plot on a piece of film. You can then use that film for photolithography which has a lot of uses, including making printed circuit boards. [Wil Straver] decided to make his own photoplotter using a 3D printer in two dimensions and a UV LED. You can see the results in the video below.
A small 3D printed assembly holds a circuit board, the LED, and a magnet to hold it all to the 3D printer. Of course, an LED is a big large for a PCB trace, so he creates a 0.3 mm aperture by printing a mold and using it to cast epoxy to make the part that contacts the PCB film.
Spice Up The Humble 16×2 LCD With Big Digits
The 16×2 LCD display is a classic in the microcontroller world, and for good reason. Add a couple of wires, download a library, mash out a few lines of code, and your project has a user interface. A utilitarian and somewhat boring UI, though, and one that can be hard to read at a distance. So why not spice it up with these large-type custom fonts?
As [upir] explains, the trick to getting large fonts on a display that’s normally limited to two rows of 16 characters each lies in the eight custom characters the display allows to be added to its preprogrammed character set. These can store carefully crafted patterns that can then be assembled to make reasonable facsimiles of the ten numerals. Each custom pattern forms one-quarter of the finished numeral, which spans what would normally be a two-by-two character matrix on the display. Yes, there’s a one-pixel wide blank space running horizontally and vertically through each big character, but it’s not that distracting.
Composing the custom patterns, and making sure they’re usable across multiple characters, is the real hack here, and [upir] put a lot of work into that. He started out in Illustrator, but quickly switched to a spreadsheet because it allowed him to easily generate the correct binary numbers to pass to the display for each pattern. It seems to have really let his creative juices flow, too — he came up with 24 different fonts! Our favorite is the one he calls “Tron,” which looks a bit like the magnetic character recognition font on the bottom of bank checks. Everyone remembers checks, right?
Hats off to [upir] for a creative and fun way to spice up the humble 16×2 display. We’d love to see someone pick this up and try a complete alphanumeric character set, although that might be a tall order with only eight custom characters to work with. Then again, if Bad Apple on a 16×2 is possible…
Continue reading “Spice Up The Humble 16×2 LCD With Big Digits”
Share Your Projects: Take Pictures
Information is diesel for a hacker’s engine, and it’s fascinating how much can happen when you share what you’re working on. It could be a pretty simple journey – say, you record a video showing you fixing your broken headphones, highlighting a particular trick that works well for you. Someone will see it as an entire collection of information – “if my headphones are broken, the process of fixing them looks like this, and these are the tools I might need”. For a newcomer, you might be leading them to an eye-opening discovery – “if my headphones are broken, it is possible to fix them”.
There’s a few hundred different ways that different hackers use for project information sharing – and my bet is that talking through them will help everyone involved share better and easier. Let’s start talking about pictures – perhaps, the most powerful tool in a hacker’s arsenal. I’ll tell you about all the picture-taking hacks and guidelines I’ve found, go into subjects like picture habits and simple tricks, and even tell you what makes Hackaday writers swoon!
To start with, here’s a picture of someone hotwiring a car. This one picture conveys an entire story, and a strong one.
Hackaday Podcast 213: Not Your Grandfather’s Grandfather Clock, The Engineering Behind Art, Hydrogen Powered Flight
Join Hackaday Editors Elliot Williams and Tom Nardi as they review some of their favorite hacks and projects of the past week. The episode starts with a discussion about the recently announced Artemis II crew, and how their mission compares to the Apollo program of the 1960s and 70s.
From there, the pair theorize as to why Amazon’s family of Echo devices have managed to evade eager hardware hackers, take a look at a very impressive SMD soldering jig created with some fascinating OpenSCAD code, marvel at the intersection of art and electronic design, and wonder aloud where all the cheap motorized satellite dishes are hiding. Stick around for some questionable PCB design ideas, a Raspberry Pi expansion that can read your mind, and the first flight of a (semi) hydrogen-powered aircraft.
Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
String Operations The Hard(ware) Way
One of the interesting features of the 8086 back in 1978 was the provision for “string” instructions. These took the form of prefixes that would repeat the next instruction a certain number of times. The next instruction was meant to be one of a few string instructions that operated on memory regions and updated pointers to the memory region with each repeated operation. [Ken Shirriff] examines the 8086 die up close and personal to explain how the 8086 microcode pulled this off and it is a great read, as usual.
In general, the string instructions wanted memory pointers in the SI and DI registers and a count in CX. The flags also have a direction bit that determines if the SI and DI registers will increase or decrease on each execution. The repeat prefix could also have conditions on it. In other words, a REP prefix will execute the following string instruction until CX is zero. The REPZ and REPNZ prefixes would do the same but also stop early if the zero flag was set (REPZ) or not set (REPNZ) after each operation. The instructions can work on 8-bit data or 16-bit data and oddly, as [Ken] points out — the microcode is the same either way.
[Ken] does a great job of explaining it all, so we won’t try to repeat it here. But it is more complicated than you’d initially expect. Partially this is because the instruction can be interrupted after any operation. Also, changing the SI and DI registers not only have to account for increment or decrement, but also needs to understand the byte or word size in play. Worse still, an unaligned word had to be broken up into two different accesses. A lot of logic to put in a relatively small amount of silicon.
Even if you never design a microcoded CPU, the discussion is fascinating, and the microphotography is fun to look at, too. We always enjoy [Ken’s] posts on little CPUs and big computers.
This Week In Security: Cookie Monster, CyberGhost, NEXX, And Dead Angles
“Operation Cookie Monster” ranks as one of the best code names in recent memory. And it’s apropo, given what exactly went down. Genesis Market was one of those marketplaces where criminals could buy and sell stolen credentials. This one was a bit extra special.
Websites and services are getting better about detecting logins from unexpected computers. Your Google account suddenly logs in from a new computer, and a two-factor authentication challenge launches. Why? Your browser is missing a cookie indicating you’ve logged in before. But there’s more. Providers have started rolling out smart analytics that check for IP address changes and browser fingerprints. Your mix of time zone, user string, installed fonts, and selected language make a pretty unique identifier. So sites like Genesis offer Impersonation-as-a-Service (IMPaaS), which is session hijacking for the modern age.
A victim computer gets owned, and credentials are collected. But so are cookies and a browser fingerprint. Then a criminal buyer logs in, and runs a virtual browser with all that collected data. Run through a proxy to get a IP that is geolocated close enough to the victim, and Mr. Bad Guy has a cloned machine with all accounts intact.
And now back to Operation Cookie Monster, a multi-organization takedown of Genesis. It’s apparently a partial takedown, as the latest word is that the site is still online on the Tor network. But the conventional domains are down, and something like eight million credentials have been captured and added to the Have I Been Pwned database.
Another researcher team, Sector 7, has been working the case with Dutch authorities, and has some interesting details. The vector they cover was a fake activation crack for an antivirus product. Ironic. There are several extensions that get installed on the victim computer, and one of the most pernicious is disguised as Google Drive. This extension looks for a Command and Control server, using Bitcoin as DNS. A hardcoded Bitcoin address is polled for its latest transaction, and the receiving address is actually an encoded domain name, you-rabbit[.]com
as of the latest check.
This extension will look for and rewrite emails that might be warning the victim about compromise. Get an email warning about a cryptocurrency withdrawal? It modifies it in the browser to be a sign-in warning. It also allows Genesis customers to proxy connections through the victim’s browser, bypassing IP address security measures. Continue reading “This Week In Security: Cookie Monster, CyberGhost, NEXX, And Dead Angles”