March 6, 2012 AT 8:32 am

A Tale of Open Source

When I started my latest project, a small electric die, I knew several things: I wanted the project to be released as Open Source Hardware, I might want to sell it someday, and I didn’t want to just make an Arduino-compatible board and use the internal pseudorandom number generator. Instead, I was going to implement a random number generator in hardware!

Unfortunately, I didn’t have any experience in hardware random number generation, so I started looking around the Internet, where I found the miniRNG project by Leon Maurer. I learned a lot from his very detailed documentation but this was my first experience in the field, and I didn’t have the money to keep reworking faulty prototypes. I wanted to implement a known working random generator in my design, and his seemed perfect.

However, when I got to his licensing section, I was saddened. He was using Creative Commons Attribution/Share-alike/Noncommercial. I wouldn’t just steal his design and strip out the noncommercial section, but with that section in place, I couldn’t release my project as Open Source Hardware or sell it to anyone.

Just below that section, though, was a ray of hope. I saw a link to ladyada.net captioned “I first learned of microcontrollers by reading about her mp3 player design. That got the ball rolling on my mRNG project.” Sensing a kindred soul, I emailed him, explained my intentions, and asked his permission to use a part of his design. Within a day, he emailed back saying that not only did I have his permission, he would go onto the website and change the license to remove the noncommercial requirement so that others could do the same if they wanted. Awesome!

I went to work, implementing a slightly modified version of his random number generator and borrowing some of the concepts from his source code, but putting it in a new, tiny design that could roll up to six different sizes of dice and show the result on a two-digit seven-segment LED display. I made something new and (in my opinion) cool, but was able to build off of an existing design to do it, which was an immense help during the debugging phase. Since this was only my second time using raw Embedded C, it was nice to not have to worry about the hardware too much.

I have enough problems as it is!

To me, this is a perfect example of how well the community can work. Out of this process, I built a cool new project, learned about hardware random number generators, and honed my skills in Embedded C. Instead of having to make it appear that I did the entire design, ripping off Leon’s hard work, all I had to do was ask him for permission. Now that the project is done, I’ve open sourced the whole thing, giving Leon plenty of attribution, and housed it on my github page. Leon, if you’re out there reading this, you’re awesome. Thank you for everything, I couldn’t have done it without you.

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  1. That’s _exactly_ how it’s supposed to work — nicely done, Harry!

  2. This is a awesome story, Harry! Thank you for sharing!

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