Rebraining an LED Marquee with a SparkCore

Wires? Where this LED scroller is going we don’t need wires. Well, except for power but everything needs power. The 90×7 LED marquee hangs over the entrance to NYC Resistor’s laser cutter room. Thanks to a Spark Core and a bit of work from [Trammell Hudson], the sign is working and attached to the network.

The original unit called for an RS485 connection for input. Other than that there wasn’t really a reason it had been collecting dust. Closer inspection of the internals proved that the display is driven exactly as you would expect: transistors for the rows and shift registers for the columns. Well, actually the columns are split into separate shift registers for the even and odd but that doesn’t complicate things too much. GPIO takes the seven row-driving transistors, two shift register clocks, data, latch, and enable for a total of twelve pins.

The Spark Core completely replaces the Atmel 80C32X2 and its RTC by pinging the network for UTC time synchronization once per day.

[via NYC Resistor]

Breaking Dridex Malware with Excel Macro Password Exploit

[Ronnie] recently posted a new chapter in his adventures in malware deconstruction. This time the culprit was an infected Excel spreadsheet file. The .xls file was attached to a phishing email claiming to be related to a tax rebate. With tax season in full swing, this type of phishing message would be likely to be opened by an inexperienced user.

[Ronnie] saved the file to a virtual machine to prevent his real workstation from getting infected. He then opened it up in Excel and noticed that it immediately attempted to run macros. A macro is essentially visual basic scripting that runs inside of the spreadsheet file. You can use it for simple automation, cell formatting, or do even more complicated tasks like reach out to external websites and pull information. This malware focused on the latter.

[Ronnie] used the alt + F11 shortcut to view the macros. Unfortunately the attackers had password protected them. [Ronnie] wouldn’t be able to view the macro code without knowing the password. Luckily, he learned of a surprisingly simple trick to completely bypass the macro password. He opened up the .xls file in Notepad++ and located three keys; CMG, DPB, and G. [Ronnie] then created and saved a new blank .xls document and password protected the macros with his own password. He opened up this new file in Notepad++ as well, and located those same three keys. He copied the keys from the new file into the old one, and saved the old file. This effectively changed the password of the malware file to the new one he had set for his new file. This is a nifty trick that apparently only works on the older .xls formats, not the newer .xlsx format.

After loading the macros, [Ronnie] quickly noticed that most of the code was obfuscated to make it difficult to analyze. There were, however, three named modules that reference possible sandbox evasion techniques. The malware first invokes these functions to detect the presence of a virtual machine or other type of sandbox. If it detects nothing, then the rest of the malware program is decoded and executed. [Ronnie] removed these checks and then executed the macro to verify that his change had worked.

The next step was to try to view the decoded instructions. The decoded gibberish was saved to a variable. The simplest way for [Ronnie] to view the contents of the variable was to have the program create a pop-up box that displayed the contents of that variable. After making this change and running the program again, he was able to see exactly what the malware was doing. The code actually invoked Powershell, downloaded a file from the Internet, and then extracted and executed that file. In the full write-up, [Ronnie] goes even further by downloading and analyzing the executable.

Measure Laser Wavelength with a CD and a Tape Measure

Obviously the wavelength of a laser can’t be measured with a scale as large as that of a carpenter’s tape measure. At least not directly and that’s where a Compact Disc comes in. [Styropyro] uses a CD as a diffraction grating which results in an optical pattern large enough to measure.

A diffraction grating splits a beam of light up into multiple beams whose position is determined by both the wavelength of the light and the properties of the grating. Since we don’t know the properties of the grating (the CD) to start, [Styropyro] uses a green laser as reference. This works for a couple of reasons; the green laser’s properties don’t change with heat and it’s wavelength is already known.

It’s all about the triangles. Well, really it’s all about the math and the math is all about the triangles. For those that don’t rock out on special characters [Styropyro] does a great job of not only explaining what each symbol stands for, but applying it (on camera in video below) to the control experiment. Measure the sides of the triangle, then use simple trigonometry to determine the slit distance of the CD. This was the one missing datum that he turns around and uses to measure and determine his unknown laser wavelength.

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The Oldland CPU 32-bit FPGA Core

Field Programmable Gate Arrays (FPGAs) let you program any logic you’d like onto a chip. You write your logic using a hardware description language, then flash it to the FPGA. You can even design your own processor and flash it to the chip.

That’s exactly what [jamieiles] has done with the Oldland CPU. It’s an open source 32 bit CPU core that you can synthesize for use on an FPGA. Not only can you browse through all the Verilog code in the Github repo, but there’s also a bunch of tools for working with this CPU core.

Included with the package is oldland-rtlsim, which lets you simulate the processor on a PC. The oldland-debug tool lets you connect to the processor for programming and debugging over JTAG. Finally, there’s a GNU toolchain port that lets you build C code for the device.

Going one step futher, [jamieiles] built a full SoC around the Oldland core. This has SPI, UART, timers, and more features you’d expect to find in a microcontroller. It can be flashed to the relatively cheap Terasic DE0-Nano board.

[jamieiles] has also ported u-boot to the processor, and the next thing on the list is the Linux kernel. If you’ve ever been interested in how CPUs actually work, this is a neat project to look through. If you want more open source CPU cores, check out OpenCores.

The Midwest RepRap Festival – Awesome Stuff in the Middle of Nowhere

It’s time once again to venture out to Goshen, Indiana for the Midwest RepRap Festival. It is the largest 3D printing con in the entire world where no one is trying to sell you anything. With a qualifier like that, it doesn’t have to be very big, but last year over 1,500 people showed up to the Elkhart county farm show complex and this year many more people are expected.

On the list of attendees is Taulman 3D, makers of fine, odd filament, Lulzbot, [Johnny] of Ultimachine, creator of the RAMBo board, MakerJuice, the FirePick Delta – the most skulled project on, and dozens of other people who make a living with 3D printing.

Of the expected attendees that are not specifically involved with 3D printing, I’m told [Ben Heck] will be there, along with someone from Adafruit and Make. The EFF might have a booth. A local radio station is doing a remote, and the servers at Wings, Etc. — one of the few area pubs — are going to clean up this weekend.

The event officially starts at 4:00pm today, Friday, March 20th. If you won’t be going the entire weekend, I’d suggest showing up on Saturday or Sunday. There will be far too many people there, and I’m slightly agoraphobic. We’ll be posting updates from the MRRF later on.

Hacklet 39: The Kerbal Way Of Doing Things

Kerbal Space Program is a space flight simulator based on an extremely stupid race of green space frogs that have decided to dedicate all their resources towards the exploration of space. It is a great game, a better space simulator than just about anything except for Orbiter, and the game is extremely moddable. For this edition of the Hacklet, we’re going to be taking a look at some of the mods for KSP you can find over on

1271491420181365398Like most hardware builds for Kerbal Space Program, [lawnmowerlatte] is using a few user-made plugins for KAPCOM, a hardware controller and display for KSP. The Telemachus plugin is used to pull data from the game and display that data on a few screens [lawnmower] had sitting around.

There are a few very cool features planned for this build including seven-segment displays, a throttle handle, and neat enclosure.

IMG_20140419_013717[Gabriel] is working on a similar build for KSP. Like the KAPCOM, this one uses the Telemachus plugin, but this one adds three eight-digit, SPI-controlled, seven-segment displays, relegendable buttons, and a Kerbal-insipired frame made out of Meccano.

[Lukas]’ KSP Control Panel is another complicated control system that breaks immersion slightly less than a keyboard. He’s using a Raspberry Pi to talk to the Telemachus server to control every aspect of the craft. From staging to opening up the solar panels, it’s all right there in [Lukas]’ control panel.

You may have noticed a theme with these builds; all of them use the Telemachus plugin for KSP. Even though it’s fairly simple to create plugins for Unity, there really aren’t that many KSP plugins build for these immersive control panels and space flight simulators. Or rather, Telemachus is ‘good enough’. We’d like to see a fully controllable KSP command pod model, just like those guys with 737 flight simulators in their garage. If you have any idea how that could happen, leave a note in the comments.

Uber-Cheap FPV Snow Sled

Has the winter blues got you RC vehicle guys down? Well, cheer up! Spring is just around the corner. In the meantime though, you can take a page out of [BenNBuilds’] book and build an FPV Snow Sled.

So how is using this Snow Sled in the winter different from any other RC vehicle? [BenNBuilds] controls it from inside his house where he stays warm and toasty. The on-board FPV camera sends video back to a receiver in the house where it can be either displayed on an LCD screen or on FPV goggles. Plus, being able to see the sled from the window doesn’t hurt either when getting in a sticky situation!

The craft it self was made on the cheap from spare parts that were kicking around. The frame is made from foam board and is powered by a ducted electric fan. A rudder similar to that of a hovercraft or swamp boat provides the steering. Since [BenNBuilds’] transmitter had a couple extra channels, he hooked up a pan and tilt system for his FPV camera. Check out the video of this puppy in action after the break….

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