Alligator Clip Strip

This is the easiest way to hook a light strip up to your Circuit Playground Express.

With the Circuit Playground powered off, hook the red clip to VOUT, the white clip to A1, and the black clip to G.

Now, power up the Circuit Playground via the USB port or by plugging in your battery. Did the lights come on? If so, hooray! Now we can start making stuff.

Troubleshooting

If the lights did not come on:

  1. Is your battery switch turned off? Turn it on!
  2. Are all your clips firmly on the correct pads, and not touching each other?

If that's not the problem, head back to the MakeCode page and re-upload your code - it might not have worked correctly.

NeoPixel Dots & Strips

The alligator clip strips are great, and absolutely foolproof, but they aren't really the best LEDs to use in a costume. They'll wiggle right off the first time someone hugs you. They're like kindergarten: easy peezy and fun, but you don't need to stay there too long.

Once you're ready for first grade, you'll need to learn about data flow direction. 

Data Flow Direction

Remember how we clipped the white wire to A1? Well, pin A1 is telling the pixels things like what color to be, how bright, and how fast to change colors. 

The NeoPixel strips "listen" for this data and then pass it down the strip. However, it can only pass the info in one direction: from IN to OUT. This means that if you hook up the wrong end of the strip, it won't light up. 

You won't break your strip if you do this -- we've all done it, there's nothing to be afraid of except a whole bunch of extra work. But it's best to get it right the first time, yes?  

Interestingly, the red and black wires don't have this issue -- power and ground can connect to either end of the strip (or somewhere in the middle, if you like). However, it's a wee bit dangerous to have just one of them hooked up and not the other, if the project is powered on, so be sure you're not connected to your battery or computer while you're messing with these wires.

Most of Adafruit's strip-style NeoPixels come with a 2-pin connector and a loose red wire and black wire sticking out of the casing. The spools are generally wound with the IN end on the outside, with a female connector, and the OUT end near the center of the spool, with a male connector. 

This is not always the case! For example, the neon strips have completely different 3-pin connectors with the male on the IN end. The NeoPixel dots also have a 3-pin connector, but the IN connector is female. This is why it's always important to check which direction they go -- if you hook them up backwards, they won't work.

NeoPixel strips have a little arrow on them showing the direction of data flow. Connect to the end the arrows are coming from, and your data info will follow the flow of the arrows.

NeoPixel dots have the word IN printed on the back of the pixel on one side. It's hard to see. If you can't tell, and you're just not sure, lay the pixel dots face up with the strip flowing away from you. If the red wire is on the left, you're holding the IN end. If it's on the right, you're holding OUT. Or look for the male connector, it's usually on the IN end.

The Neon strips have no indicator whatsoever, so you just have to guess. But it doesn't hurt the pixels if you get it wrong -- just be sure to test before installing in your project!

Hooking Up with the Bolt-On Kit

Get out your bolt-on kit. It comes with four screws and four bolts that are just the right size to fit through the Circuit Playground's mounting holes. We'll need just three of them (so if you dropped one on the floor and lost it in the carpet, no worries).

Once you've found the IN end of your strip, cut off the connector. If there's an extra black wire, you can trim that one off as well. You want to be left with a red wire, a white wire, and a black wire.

Now use our wire strippers to strip about 1/4" of shielding off each of these three wires.

Twist the stripped wires together and stick the red wires through the VOUT hole, the white wires through A1, and the black wire through GND.

If you're using NeoPixel dots, the red wire goes to VOUT, the middle wire to A1, and the remaining wire goes to GND.

Now, stick the bolts through the holes and secure them with the little nuts on the back. It helps to use a screwdriver to tighten them down. You don't need them to be super tight -- finger-tight is fine. The idea is just to hold the wires firmly in place against the pads.

Power up your Circuit Playground and watch the lights glow! This configuration is much sturdier than the alligator clip method, and will easily hold up to costume usage.

This guide was first published on Apr 08, 2020. It was last updated on Apr 08, 2020.

This page (Connect the Lights) was last updated on Jan 25, 2021.