Are Capacitive Touch Sensor & Plasma Kit compatible

Hi there,

I would like to add Capacitive Touch buttons to Wireless Plasma Kit for a project, I was wondering if the Adafruit MPR121 Capacitive Touch Sensor Gator Breakout is compatible?



Yes. You connect it to the QW/ST port. I believe you’ll need to use circuit python rather than micropython to program it. Good luck!

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Thanks Joshy-J, that’s what I thought alright.

Good luck and let us know the results,

plasma2040 is a great board and I’ve had a lot of fun with it. Here’s a video of my progress over the last year.

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Cool. I’m going to do some testing when my Plasma Kit etc… arrives, but it’s for a project that won’t start till summer. Can you tell me is it possible to connect more than one length of those lights together on the plasma2040?

I bought two of the bring your own bottle kits. Used them to light up two small artificial Christmas trees. I plan on stepping it up a notch next year and turn them on off via the Wifi.

If you hunt around you can find stuff like this, that may save you from having to go the Circuit Python route.
mcauser/micropython-mpr121: MicroPython driver for MPR121 capacitive touch keypads and breakout boards (

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This depends on the type of LED you are using. Look at this one for example:

You can see this strip has two connectors, one on each end. One side connects to the controller, the other connects to the next strip of lights. I am not sure how this works if you are using the fairy lights style LEDs, they might not have the output.

You also need to make sure you have enough power for all those LEDs.

One common mistake, by the way, is to connect the controller to the output of the LED strip. That won’t work.

the strips have little arrows on to show the direction of the signal (it goes from the controller to the last LED). I don’t know how other WS2812b LEDs do it, but make sure that’s correct if your LEDs don’t respond.

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Thanks, I will check that out. I’m testing them for a bigger project later in the year - I still have a lot to learn!!

Yes I was thinking of a waterproof version of those for down the line - I’ve been looking at some tutorials - hopefully things will clearer when my kit arrives and I can start playing around with it!! Thanks

I can confirm that it works using the test code for MPR121 just had to change the following

Create I2C bus.

i2c = busio.I2C(board.SCL, board.SDA)
i2c = busio.I2C(board.GP5, board.GP4)

and that is just the start of my learning curve!!!