Jimmie P Rodgers' Lots of LEDs (LoL) Shield

June 7, 2011

LoL Shield

Last week I purchased seven thousand LEDs, 150 feet of 2 inch wide velcro (hook side only) and the internal reflector for a street light. The velcro and reflector are for future projects, but I didn’t have enough project ideas for seven thousand LEDs.

Happily, I remembered Jimmie P. Rodgers’ LoL Shield!

This “Lots of LEDs” shield for the Arduino has a nine by fourteen grid of LEDs, each individually addressable through the magic of charlieplexing.

I contacted Jimmie on twitter and asked if the LoL shield PCBs were available without the LEDs included in the kit, once that was confirmed, I ordered five PCBs.

My coworker bought one of the surplus bags of 1000 LEDs, and he also ordered five bare PCBs. We hope to use I2C or SPI to coordinate among multiple Arduinos, and thus combine multiple LoL shields into a single scrolling display.

If you want to understand charlieplexing in greater detail, check out Jimmie’s posts about the hardware and software design of the LoL shield. These posts provide all sorts of interesting details such as calculating the maximum number of charlieplexed LEDs per input pins and using bitmath to compress animation frames.