Reverse Engineering Altium Files

October 15, 2014 by Brian Benchoff 71 Comments

Several times in the last few weeks, I’ve heard people say, ‘this will be the last PCB I design in Eagle.’ That’s bad news for CadSoft, but if there’s one thing Eagle has done right, its their switch to an XML file format. Now anyone can write their own design tools for Eagle without mucking about with binary files.

Not all EDA softwares are created equally, and a lot of vendors use binary file formats as a way to keep their market share. Altium is one of the worst offenders, but by diving into the binary files it’s possible to reverse engineer these proprietary file formats into something nearly human-readable.

[dstanko.au]’s first step towards using an Altium file with his own tools was opening it up with a hex editor. Yeah, this is as raw as it can possibly get, but simply by scrolling through the file, he was able to find some interesting bits hanging around the file. It turns out, Altium uses something called a Compound Document File, similar to what Office uses for Word and PowerPoint files, to store all the information. Looking through the lens of this file format, [dstanko.au] found all the content was held in a stream called ‘FileHeader’, everything was an array of strings (yeah, everything is in text), and lines of text are separated by ‘|’ in name=value pairs.

With a little bit of code, [dstanko] managed to dump all these text records into a pseudo plain text format, then convert everything into JSON. You can check out all the code here.

Playing StarCraft On An ARM

July 31, 2014 by Brian Benchoff 25 Comments

Starcraft

Except for the really terrible Nintendo 64 port, StarCraft has always been bound to desktop and laptop PCs. Blizzard could take the code for StarCraft, port it to an ARM platform, put a version on the Google Play an iTunes store, and sit there while the cash rolls in. This would mean a ton of developer time, though, and potentially years tracking down hard to find bugs.

Or one random dude on the Internet could port StarCraft to an ARM platform. Yes, this means all the zerg rushes and dark templar ambushes you could possibly want are available for tablets and Raspberry Pis.

This godlike demonstration of compiler wizardry is a months-long project of [notaz] over on the OpenPandora team. Without the source for StarCraft, [notaz] was forced to disassemble the Win32 version of the game, convert the disassembly to C with some custom tools, and recompile it for ARM while linking in all the necessary Win32 API calls from the ARM port of Wine. Saying this was not easy is an understatement.

If you have an OpenPandora and want to relive your heady days of youth, you can grab everything you need here. For anyone without an OpenPandora that wants to play StarCraft on a Raspi, you might want to get working on your own recompiled port. Video below.

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Programming Pi Games With Bare Metal Assembly

June 23, 2014 by Brian Benchoff 21 Comments

pifox While the most common use for a Raspberry Pi is probably a media center PC or retro game emulator, the Pi was designed as an educational computer meant to be an easy-to-use system in the hands of millions of students. Team 28 at Imperial College London certainly living up to the Raspberry Pi Foundation’s expectations with their bare metal assembly clone of Star Fox, aptly titled PiFox.

This isn’t the first time a college course has taken up the task of developing software for the Pi without an operating system; a few years ago, Cambridge University started that off with a series of bare metal tutorials for the Pi that included drawing graphics on the screen and playing around with USB keyboards. PiFox greatly expands on what those early tutorials could do, reading an NES joystick from the GPIO pins, sound with DMA, and rendering 3D objects.

If you’d like to build PiFox for yourself, or better yet, expand on the existing build, all the code is up on Github. There’s also a Raspberry Pi emulator for Linux, just in case you have an ARM assembly bug you just can’t scratch with a Raspberry Pi.

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The Sega Mega Drive Dev Kit

June 18, 2014 by Brian Benchoff 13 Comments

sega While most homebrew video game development has focused on the original NES, Atari consoles, and has produced a few SNES games, there is another console out there that hasn’t seen much love. Sega’s classic console, the Genesis or Mega Drive, depending on where you’re from, was an extremely capable machine with amazing capabilities for its time. [Chris] figured the Mega Drive would make a good target for an all-in-one development kit, and with a lot of work he managed to put one together.

The standard cartridge for the Genesis or Mega Drive is just a simple ROM chip wired directly into the console’s address space. [Chris] took a cheap FPGA and some dual port ram to create a seamless interface between the modern world and the inside of this ancient console, allowing him to load every Mega Drive game off an SD card, as well as use modern tools to modify old games, or even create new ones.

To demonstrate his dev kit, [Chris] took a copy of Sonic 1, and using the debugger and GDB, gave himself infinite lives. It’s a very cool demonstration, searching through all the commands executed by the Megadrive CPU with the standard Linux debugging tools.Going through the trace, [Chris] found the instruction that decremented that value representing Sonics lives, replaced it with NOPs, in effect giving himself infinite lives. This is a lot like how the Game Genie works, only using much, much better tools.

Of course a USB dev kit wouldn’t be much use if it could only modify existing games. The real power of [Chris]’ work comes from being able to develop your own demos, games, and homebrew apps.

[Chris] needed to write a small homebrew Mega Drive app for the ROM loader portion of his dev kit using SGDK. Disassembling his own code with the dev kit, he was able to take a look at the instructions, and potentially even modify his loader.

It’s a really impressive technical accomplishment, and something that could be a boon to the extremely small homebrew scene for the Mega Drive. All the boards, code, and everything else are available over on [Chris]’ github, with the entire project written up on hackaday.io. Videos below.

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MiniBloq IDE, Graphical Programming For Robots Of All Sizes

May 8, 2014 by Brian Benchoff 8 Comments

MiniBloq

The Arduino IDE only brings the ire of actual EEs and People Who Know Better™, but if you’re teaching robotics and programming to kids, you really don’t want something as simple as a text editor with a ‘compile’ button. For that educational feat, a graphical system would be much better suited. [Julián] has been working for months to build such a tool, and now miniBloq, the graphical programming tool for just about every dev board out there, has a new release.

The idea of a graphical programming language for robotics has been done before, most memorably with the Lego Mindstorms programming interface. That was closed source, of course, and only worked with the magical Lego brick that allowed you to attach motors and sensors to a child’s creation. miniBloq takes the same idea and allows the same programming environment to work with dozens of dev boards for robots of every shape and size. Already, the Pi-Bot, SparkFun RedBot, Maple, Multiplo DuinoBot, and anything based on an Arduino Leonardo works with miniBloq, as will any future dev boards that understand C/C++, Python, or JavaScript. It’s not just for powering motors, either: there’s a few Python and OpenCV tutorials that demonstrate how a robot can track a colored object with a camera.

The current version of miniBloq can be downloaded from the gits, with versions available for Windows and *nix. The IDE is written with wxWidgets, so this could also be easily ported to OS X.

Python With Braces

February 10, 2014 by Brian Benchoff 110 Comments

python

If there’s one thing about Python that’s slightly disconcerting, it’s the complete lack of braces, or as they’re called in American English, suspenders. A feature of every variety of C, Java, PHP, Perl, and a whole bunch of other very powerful languages, braces make things more legible and don’t rely on precise indentation. [Ruby] and [Eran] have come up with a way to use these punctuation marks with Python in a project they call Python with Braces.

As its name implies, Python with Braces doesn’t care about indentation: you’re free to make you code extremely ugly, or write your code properly in K&R style. Each line is terminated in a semicolon, and blocks of code with only one statement don’t require curly braces, just like C and Java.

Right now [Ruby] and [Eran] have a Windows installer with an OS X package on its way. Executing a Python with Braces script only requires executing it with a ‘pythonb’ executable instead of the normal ‘python’ executable.

Using A Computer To Read Braille

February 9, 2014 by Brian Benchoff 6 Comments

braille

[Matthiew] needed to create a system that would allow a computer to read braille. An electromechanical system would be annoying to develop and would require many hardware iterations as the system [Matthew] is developing evolves. Instead, he came up with a much better solution using a webcam and OpenCV that still gets 100% accuracy.

Instead of using a camera to look for raised or lowered pins in this mechanical braille display, [Matthiew] is using OpenCV to detect the shadows. This requires calibrating the camera to the correct angle, or in OpenCV terms, pose.

After looking at the OpenCV tutorials, [Matthiew] found a demo that undistorts an image of a chess board. Using this same technique, he used fiducials from the ARTag project to correctly calibrate an image of his mechanical braille pins.

As for why [Matthiew] went through all the trouble to get a computer to read braille – something that doesn’t make a whole lot of sense if you think about it – he’s building a braille eBook reader, something that just screams awesome mechanical design. We’d be interested in seeing some more info on that project as well.