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Still alive? 🪦 Yes, it’s true this project did get dropped for awhile, it’s been about 3 years since the last blog post. ...

A tennis ball sized, 20 sided, LED clad, regular polyhedron Introduction The major challenge of making a smaller LED cube in my opinion is the LED panels. Commercially available panels are designed for video walls and typically made at 64x64 pixel as a minimum size. This seems to be a good trade off between cost/complexity/light efficiency. On my previous project mini-led-cube I had overcome one of the major hurdles of creating a smaller cube, because I had designed and built my own custom high density* LED panels. ...

Background Having seen a few projects creating LED cubes from panels used for LED video-walls I knew I had to try to build one myself. If you haven’t seen these before here are some examples I’ve seen. along with some notable people involved in their creation: @zzaurak, @1HappyTeddybear, @esden, @kernlbob. These cubes are all built using COTS video wall panels. The mains ones I’ve seen used are in the 64x64 pixel size and either 2.5mm (P2.5) or 2mm (P2) pixel pitch. These panels feature a low cost multiplexing system on the back of the PCB, and a dense array of LEDs on the front. Surprisingly these panels are made surprisingly cheap, with panels from China costing $20-$40 range, which for 4096 RGB LEDs is very cheap! ...

RTL Architecture The original version of the frame grabbing PCB used an iCE40 HX8K FPGA. This turned out to be a little small for the features I wanted to add. I managed to get it to a state where it would capture images from the Boson 320, but everything was hardwired together, and not easy to alter or reuse. In order to improve module reuse and extendability a standard interface should be used. There are a few of these internal bus architectures available. I’ve decided to use wishbone, Mainly because I’ve been able to find existing wishbone modules that perform most of the major functionality of the frame grabber I’m building. ...

The new hardware for the Boson Frame Grabber will be based around the Lattice ECP5 family. Lattice make available a free IDE for this FPGA assuming you are not using a model with embedded SERDES. Since we are not, it’s perfect for our application. ...