This is the first part of our PIXIE tutorial serie. You can read about the genesis of our open source and open hardware continuous integration status light. In this blog post, we will give you the precise list of all materials, parts and tools you’re going to need to build your own PIXIE indicator. The full set of materials shouldn't cost you more than $100 for 1 central unit and 4 status lights (laser cut price not included).
-1 particle Photon
-1 breadboard (400 contact points)
-4 USB-A sockets (side, angled 90°)
-4 addressable 16 LEDs rings (WS2812B)
-1 box of jumper wires for breadboards
-1 quadruple bus buffer gates (SN74HCT125N)*
-1 micro-USB phone charger (5V/2A)
-5 flat 1m smartphone cables (USB A plug + USB B micro plug)
The general rule for the power supply is that PIXIE needs 500mA for the main unit and 60mA for each LED light at maximum brightness. That’s 4.5A for four light rings and the main unit. Our setup uses more or less 25% of maximum brightness per LED, so 2A power supply should be more than enough. Using 1A charger may lead to CPU being stuck in a restart loop.
There’s large number of very similar LED controllers and chips. Most of them can be used here, but our setup was prepared for these particular components. Using different LED controllers, CPU or bus buffer gates may require adjusting the software, the hardware and/or the cover. If you’d like to build PIXIE like us, we strongly advise you to use the components we listed.
What is that bus buffer gate for? Photon outputs 3.3V data and we need 5V data to work with WS2812B LEDs. This chip takes 3.3V signal and makes it 5V - as simple as that.
-25 cm (10 inches) of clear 3M Dual Lock Reclosable Fastener (width: 25.4 mm / 1 inch)
-150 cm (60 inches) of white bonding double sided foam tape (width: 25.4 mm / 1 inch)
-1 sheet of thicker black paper
-1 polypropylene sheet 1 mm thick (clear) laser cut with this pattern:
-Multimeter (optional but useful for troubleshooting)
-wire stripper (optional but convenient)
Once you have all the ingredients, what you will only miss is our next blog post to start the construction. To be continued in our next blog post about assembling the hardware part.
- Gosia FiedorowUI Designer