kmontag / here2019

Usage

See featherstream/README.md and kontrol/README.md for usage overviews of the two main devices.

Assembly

In addition to the build instructions in featherstream/README.md and kontrol/README.md:

DotStar strip

• Compile and print things/dot_star_endcap.scad.
• Cut the strip (https://www.adafruit.com/product/2237) to the desired number of LEDs along the midpoint of the metal contacts.
• Input side:
  • Run the female end of a 4-wire cable set (https://www.adafruit.com/product/744) through the large endcap fitting, with the free wire ends coming out of the larger end.
  • Run the wires through the 4 holes in the smaller endcap fitting. Check your strip to see the positions of the DI/CI contacts, and order the wires such that:
    • Red goes to VOC (+5V)
    • White goes to CI
    • Yellow goes to DI
    • Black goes to GND
  • Solder the wires to the contacts
  • Test the connection by connecting to an assembled feather
  • Put some hot glue or superglue onto the soldered connections for extra security.
  • Slide the smaller endcap over the strip, and place an M3 nut (https://www.amazon.com/dp/B07JD4ZLFT/) into the receptacle.
  • Put some hot glue or superglue on the outside of the endcap where the wires enter.
  • Wrap a bunch of electric tape around the 4-wire cable, between the large endcap and the strip. The goal is to reduce strain on the soldered connections once the endcap is fastened, so position it such that it forces a little bit of slack in the wires when the large endcap slides all the way up.
  • Slide the large endcap over the small one, and screw an M3 screw (https://www.amazon.com/dp/B01LZYC586/) through the hole, into the nut, and down far enough that it presses agains the strip pretty hard. The goal is to hold the endcap in place without placing strain on the soldered connections.
• Output side:
  • If chaining strips together, this is the same as the input side except:
    • Use the male side of the 4-wire cable instead of the female.
    • Make sure you place the over-screw onto the 4-wire cable before soldering.
    • Make sure you're soldering to the CO/DO side of the contacts (not CI/DI).
  • If not chaning strips together, you can just seal this off with the smaller endcap piece or some shrink wrap / tape.

Development - running a local featherstreamer server

featherstreamer is what the Pis run to serve pixels to feathers. There are two components:

featherstreamer

This is the main data server. Before running it:

• Place any video files you want to stream in kontrol/media-src/. These can be anything readable by ffmpeg.
• Run make media to compile the files into raw pixel data that can be streamed without processing overhead. The built files live in kontrol/media-build/.
• Run make in kontrol/.

To run the program, in kontrol/featherstreamer:

npm start

You can also use npm run start-dev during development, to pick up changes to source files automatically.

To get a Feather to see your local featherstreamer server, you'll need to make compile-time changes. In your secrets.h, place the following:

#define SECRET_PAIRED_SSID "Your home SSID"
#define SECRET_PAIRED_PASSPHRASE "Your WiFi password"
#define SECRET_SERVER_IP IPAddress(192, 168, 0, 1) // Or whatever your computer's local IP address is

And then compile and upload to your Feather.

featherstreamer-web

This is the web interface that's normally accessible at http://192.168.8.1 on a Feather's hosted network. It shows details about connected devices, and allows you to simulate interactions with the hardware.

Before starting, run make in kontrol/. Then start the server with npm start in kontrol/featherstreamer-web. The page should open automatically in your browser; if not, it's accessible at http://localhost:3000.

Note the UI won't be functional unless the featherstreamer server is also running locally.

Development dependencies

• PlatformIO for building the feather software: brew install platformio
• OpenSCAD for building 3D-printable objects: brew cask install openscad
• Ansible for configuring a Pi: brew install ansible
• Node/NPM for running the featherstreamer server (the thing the Pi uses to stream video) locally