Every year, Austin (Texas) has an event for makers, tinkerers, and other nerds who like to build. It’s called SXSW Create. This year, I was manning a booth with The Robot Group. Sparkfun Electronics was giving away these little badges:
They gave you a bag of parts and you waited until there was a soldering station open. Then you just soldered the headers on, threw in some batteries, attached a lanyard, and you had a microcontroller around your neck.
They said they were reprogrammable, so I decided to turn mine into a name tag.
I investigated and found the support files. The page containing them and the installation instructions can be found here. Then I downloaded the Arduino IDE, which will allow us to reprogram the Badger.
I initialized the LED matrix:
#include <SparkFun_LED_8x7.h> #include <Chaplex.h> // Global variables static byte led_pins[] = {2, 3, 4, 5, 6, 7, 8, 9}; // Pins for LEDs void setup() { // Initialize LED array Plex.init(led_pins); // Clear display Plex.clear(); Plex.display(); }
Next I looked at Sparkfun_LED_8x7.h. (.h files are to .cpp files what tables of contents are to books.) I found the scrollText() method and the stopScrolling() method. I messed around for a bit and found that I need to scrollText(), wait for a bit, then stopScrolling().
In loop(), I made the text “The Robot Group” scroll across the screen.
Plex.scrollText("The Robot Group", 1); delay(10000); Plex.stopScrolling(); delay(2000);
Then I poked around a bit more and found the drawing methods. I prefixed the text with a very pixellated version of the group’s logo.
// Logo Plex.clear(); // Logo: Circle Plex.line(2, 0, 0, 2); Plex.line(0, 2, 0, 4); Plex.line(0, 4, 2, 6); Plex.line(2, 6, 5, 6); Plex.line(5, 6, 7, 4); Plex.line(7, 4, 7, 2); Plex.line(7, 2, 5, 0); Plex.line(5, 0, 2, 0); // Logo: Man Plex.line(1, 7, 3, 3); Plex.line(6, 7, 4, 3); Plex.line(0, 2, 7, 2); Plex.line(4, 1, 3, 1); // Logo: Display for 5 seconds Plex.display(); delay(5000);
The Robot Group’s logo:
BadgerHack version:
And so I reprogrammed my badge and then did likewise with some of the other members’ badges. It was quite entertaining for me.
Here is the finished code. BadgerStickTRG.zip