Defcon 20 Badge POV

Yesterday I planned on going to several Defcon talks, and got to the convention center a little bit early to make sure I got a seat. To kill time I decided to go hang out in the Hardware Hacking Village and tinker around with the propeller tool for the badge. I didn’t really know what I wanted to do with it, but thought there must be something cool I can do with this thing.

The night before I had my badge infected by a goon and it began flashing a pattern on the LEDs. I began waving my badge in the air thinking that it must be some sort of POV (Persistence of Vision) or something. Turns out it appears to be completely random, so nothing was ever spelled out.

I decided to try to make the badge spell something out when I waved it in the air. I have never used the spin language before so it took me quite a while to get something that would even compile and run on the badge. It also took me a while to figure out what the IDs of the LEDs  that I was trying to manipulate were… 16-23 duh! Anyway after defining a bitmap for a couple letters, I was able to flash the individual lines of the letters in sequence and produce a pretty clear ‘D’ in the air. I spent a little bit more time defining the  rest of the letters in DEFCON and by noon had the badge writing ‘DEFCON’ in block letters as I waved it around.

People began to flock toward me and ask me about what I had done. I showed them the dirty code I threw together to get it to work, and was pretty embarrassed by the way I was individually writing each letter one line at a time. I ended up taking someones suggestion and changing it to say ‘DEFCON XX’ and then people just started asking me to flash it on their badges! I won’t lie, I felt like a celebrity for a couple minutes there. One guy even suggested I find the documentary crew and get them to film what I had created. I tried, but the film just didn’t capture it well.

Needless to say I didn’t leave the HHV until around 5PM and missed all the talks I had planned to attend. It was totally worth it, met some awesome people, and got to feel slightly famous for a couple hours.

X spacing was off, but it took me 54 shots to actually capture it. I fixed the bug, but I’m not going to try to capture it again.

The video doesn’t really do it justice since the framerate screws it up, but here is the video anyway.

If you want to load this on your badge, just use the propeller tool and the code below.