LED Cubes

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In 2014 cube-mania struck the space.

pycubedemo contains drivers for the various cube boards, a cube emulator and a repository of demo patterns.

The Cubes

Mini cube

A small cube made of 64 (4×4×4) charlieplexed 5mm LEDs, completed around the end of April. Constructed by pbrook.

Firmware: charliecube.

Connection is over USB. Talk to it with python cube.py -P /dev/ttyACM0 -s 4.

Blog post with videos.

LED array

Not a cube at all, 32×8 RGB LEDs in a rectangular array, split into four 8×8 boards. Made around June by pbrook.

https://www.flickr.com/photos/ajtag/14503776395/

Hardware and firmware here.

Martyn's desktop cube

An 8×8×8 cube of 10mm RGB LEDs in an acrylic case. Constructed largely by Joran. Split into four independent boards, each containing an ATMEGA328 and three TCL5940 PWM LED drivers. The LED drivers control one colour component each (red, green or blue). Multiplexing enables each driver's 16 output channels to control 128 LEDs.

A Gizmo (small x86 board) drives the microcontrollers. It runs demo patterns in a loop when idle and listens for TCP connections over wifi. When at the space it has hostname "cuboid". Talk to it with python cube.py -P cuboid:3000.

Build time: one week. Components:

  • 512 10mm RGB LEDs: £100
  • 16 PCBs (4 populated, the other 12 are structural): £40
  • ICs: 4×ATMEGA328, 12×TCL5940NT: £50ish?
  • Gizmo board, ATX PSU: spare
  • 50×50×50cm clear acrylic case, 3mm thick: £45

Video (bare cube, no case).

Hardware and firmware is here. Protocol is the same as for the LED array.

ÜberCube

The big one, an 8×8×8 RGB cube 3 metres on a side. Each pixel is a strip of 6 RGB LEDs inside a pair of nested plastic drinking cups, and is driven by an individual ATtiny25.

Vertical strings of 8 pixels are suspended from wooden beams atop the cube; each plane of 8 strings is connected together in a zigzag arrangement to make linear strings of 64 pixels. Only three wires are used (ground, power and data): each pixel controller consumes 24 bits of serial data per frame and passes the rest along the string.

Hardware and firmware: lightcube.

Exhibition

The ÜberCube was exhibited at Leeds City Museum on Friday 3rd October as part of Light Night 2014.

Matt talking about the cube and the space: Hackspace Cube.

References:

Tweets

Youtube