The current LED Wall (as of Fall, 2014) is 768 WS2811 LEDs in a 32×24 grid. The LEDs are in twelve 8×8 panels where the first LED is in the top left and goes down, then right one, and back up, repeating. This snake pattern continues across four panels, then restarts on the next set of four. This is because the original panels were separate pieces and built from recycled leftovers.
The LEDs draw ~60ma each. 60ma*768=4.6A, so a 5v5a power supply is used to power the three rows of grids.
The LEDs are told what to do through a Teensy 3.1 connected to a Raspberry Pi. By connecting to the Pi you can either use PlatformIO or the Arduino build environment to change the animations on the wall.
The Raspberry Pi is on the network, nominally at 172.16.6.2. The login user is 'pi' and the password is 'raspberry'. Once logged in a user can call
~/cd platformio ~/platformio/platformio run -t upload
which will compile the code in ~/platformio/src/main.cpp and send it to the wall Teensy.
See also the PlatformIO quickstart guide
The teensy has previously been programmed to accept data from the pi as a bitstream and send whatever it gets to the wall, no exceptions. it listens for a maximum of 768 RGB values (3 bytes each). RGB tuples can be any color except black (0). an all black pixel (0,0,0) signals the start of a new frame. in this way video was streamed from a laptop to the wall, making it into a low-res jumbotron.
The teensy could be paired with the pi to stream animations sequenced in a looping queue. Then people could create new animations and dynamically adjust the queue without affecting the teensy. this would be easier than reprogramming the teensy over and over. what format the queue and the animations take is unknown at this time.
LED Wall 2014?
Mid 2013, the CORE community of Burning Man gave VHS an LED array for a long term loan. This was put up on a prominent wall and was the most consistently working project at VHS for the duration of its stay.
Due to some unfortunate communication issues, the wall was returned Summer of 2014.
To fill the gaping void in all of our hearts, Wall 2.0 was funded and installed Fall 2014.