Read through this guide before commiting to any hardware. This project offers a lot of potential for customization, and you might want to build something that works a little differently.
My setup happened to include:
- Adafruit Feather HUZZAH ESP8266 WiFi microcontroller
- 10mm red LED
- 220 Ohm resistor
- 5V DC power supply
- Panel-mount DC barrel jack
- 2-pin JST Plug & Receptacle Cable Set
You will also need the usual electronics project bits like wire and soldering paraphernlia.
There are some other ESP8266 board variants (like our HUZZAH ESP8266 breakout) and the code we provide should work on them with little or no modification. The Feather HUZZAH was chosen because it offers a lot of flexibility for just a few extra bucks…built-in USB programming (No FTDI cable needed), the option to power the project using a USB phone charger you might already have (instead of the DC jack & power supply), and built-in LiPoly battery charging if you wanted to make something that’s self-contained. It all depends on how you want to build and enclose it.
The circuit layout for the one I built looks like this:
The + leg of the LED is connected through a 220 Ohm resistor to pin 15 on the HUZZAH board (use the labels on the back side of the board, it’s easier to tell which pin is which). The – leg of the LED as well as GND on the HUZZAH board are both connected to the – lug of the DC jack. The HUZZAH USB pin is connected to the + lug.
Not shown here, my build added a JST plug & receptacle on the DC power input so I can separate the electronics & enclosure…yours might not need that, I’ll explain the “why” below.
If you’re powering it through the USB port, the circuit’s even simpler…you can leave off the DC jack and just wire up the LED and resistor (the – leg goes to GND). Or simpler still, leave that out and use the onboard LED on pin #0…no soldering at all. Or add some DotStars or one of our tower lights, whatever achieves the look you want and you’re willing to add the necessary code for. The single LED was an experiment in minimalism…headaches are horrible and I wanted this a no-brainer. (rimshot!)
If you use the panel-mount DC jack with a “tip positive” power supply (like the ones we sell), the large lug is the positive (+) connection, and the outer of the two small lugs is the ground or negative (–) connection. The middle lug is not used here.
If using a DC jack as shown here, do not plug in USB and the DC power supply at the same time! Unplug the DC power source before uploading code to the board.
“Dressing up” the project is totally not required, but can be a lot of fun! It adds a bit of arts & crafts rather than being all about electronics or code.
Some of the most clever and “high concept” ambient displays are themed or camoflaged to fit in their environment. How about an umbrella stand that lights for rainy weather, or a whole ceiling constellation that twinkles in anticipation of good stargazing? Mine isn’t nearly that cool…but as it was somewhat health-related, the plastic pill bottle seemed reasonably thematic.
My choice of enclosure created a “ship in a bottle” situation. Adding a JST plug & socket (not shown in the wiring diagram) between the DC jack and electronics made it easier to work on the soldering. Most normal enclosures probably won’t need this.
Adding some glass marbles helped camouflage the electronics inside and adds heft so the bottle stays put.
Clearly, this design is not fit for a home with small children. Keep context in mind when designing, that it’s safe and conveys an appropriate message.