Adding one nOOd is fun, but adding a handful of sequence-able and code-able nOOd is way more fun.
If this looks intimidating, or if you don't care about software control, you can get a similar effect by using multiple single nOOds each hooked up to its own coin cell battery holder. If you're ready for a Project, and not afraid of a little soldering, read on.
Identify the + and - ends of your nOOds by sight, and confirm by touching the bare metal ends to each side of a coin cell battery. Mark the nOOds with some tape so you remember which end is which.
We'll solder a red wire to the + end and black wire to the - end. To get a really good solder connection, make a bend in the nOOds connector and a bend in the wire, and hook them together before soldering. This will make it far less likely for your solder joint to break, leaving you in the dark.
Solder a red wire to the + end and a black wire to the - end of all your nOOds. The wire lengths will depend on your project. Remember that both wires need to reach back to the microcontroller.
Now let's add the resistors. I'm using 220ohm resistors. Use something in that neighborhood to keep your nOOds from burning out - the QT Py puts out 5v of current, and the nOOds prefer closer to 3v. They'll break if you feed them too much.
Bend the resistor leg into a loop and wind it around itself to give yourself a place to hook your wire. Solder a wire to each end -- it doesn't matter which end is which -- and cover the whole resistor with heat shrink.
Each red nOOd wire needs to go to its own GPIO pin, so we can light them individually from the software.
Solder one of the red wires from your nOOds to the yellow wire and one to the green wire on the Stemma connector. We'll use these two wires as GPIO pins.
Twist all the black wires from your nOOds together and solder them to the black wire on your Stemma connector. All the black wires go to G (ground).
I have a third nOOd in my project, so I'll use one of the other GPIO pins on the Stemma for the remaining red wire. Additional nOOd could be added to the rest of the available pins, and all can connect to the same G pin.
This is a great moment to stop and test your wiring. Skip ahead to the CircuitPython page and install the software, then upload your code.
Plug your QT Py in via the USB port and see if your nOOds come on.
If most but not all of them come on, check the faulty one to be sure you didn't mix up the + and - ends. If none of them come on, the trouble is probably with your software. Head back to the software page and try uploading again.
Once the nOOds are all coming on, let's add our power switch.
The JST breakout is a handy little thing with an on-off switch built in. You can plug any of our LiPoly batteries in and run your project for hours.
Solder 5V on the QT Py to the Sw pin (the one connected to the switch) and connect G to G.
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