An NXT compatible I2C breakout is on the board, however I haven’t tested it.
Licensed under CC-BY.
Notes on Production: If you’re making a small run, I would recommend OSHPark, the price I’ve been quoted was ~$25 for 3, and includes free shipping. They also include ENIG coating in the price. For larger runs, Seeed is hard to beat.
Bill of Materials
- 1 x Teensy 3.1. A teensy 3.0 should work as well, but if you’re buying new, there’s no good reason not to use the 3.1
- 8 x 120 ohm resistors (signal filtering)
- 3 x 3 position 5mm screw terminals
- 2 x 14 male header pins
- 2 x 14 female header pins
- 2x 12mm tactile switches
- 2x 1.4kohm i2c pullup resistors
- 1x NXT i2c cable
Switches are connected to pins 9 (SW1), and 10 (SW2)
Notes on Signal Filter Resistors: During a competition we ended up with all but 1 working strip. Investigating the failure we found all the first LED in each strip dead. I believe the cause of this is transient voltage spikes on the data lines. Our current approach is to use filter resistors directly connected at the strip end, not the board end. In this case, replace the 120 ohm resistors with 0 ohm (ie. short lengths of wire)