# BLE Synth with the Feather nRF52840 and Circuit Playground Bluefruit ## Overview ![](https://cdn-learn.adafruit.com/assets/assets/000/088/038/medium800/feather_edited_P1220373.jpg?1580840079) In this project, Bluetooth Low Energy (BLE) is used to have a **Feather nRF52840** and **Circuit Playground Bluefruit** communicate with each other to create a wireless 8-bit music synthesizer. The Feather has 12 buttons attached to its I/O pins. Each time a button is pressed, it sends a BLE packet to the Circuit Playground Bluefruit. When the Circuit Playground Bluefruit receives those packets, it swirls its on-board NeoPixels in a specific color and plays a tone. ### The Bluefruit Playground App This project was inspired by the tone example in the **Bluefruit Playground App**. With the app, you may connect your Circuit Playground Bluefruit board to your iOS device and then play with a series of examples, each with a user interface to allowing control of the Circuit Playground Bluefruit sensors. One of those examples has a piano keyboard in the app and when the keys are pressed, they cause a tone to play from the Circuit Playground Bluefruit. I thought it would be cool to recreate this concept with hardware. ![](https://cdn-learn.adafruit.com/assets/assets/000/088/036/medium800/feather_edited_P1220378.jpg?1580840062) [Check out this Learn Guide on the Bluefruit Playground App](https://learn.adafruit.com/bluefruit-playground-app) ## Project Video https://youtu.be/mBScFbHKeEY ## Parts ### Adafruit Feather nRF52840 Express [Adafruit Feather nRF52840 Express](https://www.adafruit.com/product/4062) The **Adafruit Feather nRF52840 Express** is the new Feather family member with Bluetooth® Low Energy and _native USB support_ featuring the nRF52840!  It's our take on an 'all-in-one' Arduino-compatible + Bluetooth® Low Energy with built-in USB... Out of Stock [Buy Now](https://www.adafruit.com/product/4062) [Related Guides to the Product](https://learn.adafruit.com/products/4062/guides) ![Angled shot of a Adafruit Feather nRF52840 Express. ](https://cdn-shop.adafruit.com/640x480/4062-02.jpg) ### Circuit Playground Bluefruit - Bluetooth® Low Energy [Circuit Playground Bluefruit - Bluetooth® Low Energy](https://www.adafruit.com/product/4333) **Circuit Playground Bluefruit** is our third board in the Circuit Playground series, another step towards a perfect introduction to electronics and programming. We've taken the popular Circuit Playground Express and made it even better! Now the main chip is an nRF52840... Out of Stock [Buy Now](https://www.adafruit.com/product/4333) [Related Guides to the Product](https://learn.adafruit.com/products/4333/guides) ![shot of a Black woman's neon-green manicured hand holding up a Circuit Playground Bluefruit glowing rainbow LEDs.](https://cdn-shop.adafruit.com/640x480/4333-11.jpg) ### Adafruit STEMMA Speaker - Plug and Play Audio Amplifier [Adafruit STEMMA Speaker - Plug and Play Audio Amplifier](https://www.adafruit.com/product/3885) Hey, have you heard the good news? With Adafruit STEMMA boards you can easily and safely plug sensors and devices together, like this **Adafruit STEMMA Speaker - Plug and Play Audio Amplifier**. Like the name implies, it's got a class D audio amplifier on board, and our... Out of Stock [Buy Now](https://www.adafruit.com/product/3885) [Related Guides to the Product](https://learn.adafruit.com/products/3885/guides) ![Top view of a black speaker breakout board connected to a round microcontroller via alligator clips. A music note animation emits from the speaker.](https://cdn-shop.adafruit.com/product-videos/640x480/3885-05.jpg) ### Colorful Round Tactile Button Switch Assortment - 15 pack [Colorful Round Tactile Button Switch Assortment - 15 pack](https://www.adafruit.com/product/1009) Little clicky switches are standard input "buttons" on electronic projects. These work best in a PCB but [can be used on a solderless breadboard as shown in this tutorial](http://www.ladyada.net/learn/arduino/lesson5.html). The pins are normally open (disconnected) and... In Stock [Buy Now](https://www.adafruit.com/product/1009) [Related Guides to the Product](https://learn.adafruit.com/products/1009/guides) ![Top-down shot of 15 colorful round tactile button switches in green, yellow, red, blue, and white.](https://cdn-shop.adafruit.com/640x480/1009-07.jpg) ### 3 x AAA Battery Holder with On/Off Switch and 2-Pin JST [3 x AAA Battery Holder with On/Off Switch and 2-Pin JST](https://www.adafruit.com/product/727) This battery holder connects 3 AAA batteries together in series for powering all kinds of projects. We spec'd these out because the box is slim, and 3 AAA's add up to about 3.3-4.5V, a very similar range to Lithium Ion/polymer (Li-Ion) batteries and have an on-off switch. That makes... In Stock [Buy Now](https://www.adafruit.com/product/727) [Related Guides to the Product](https://learn.adafruit.com/products/727/guides) ![Front angled shot of 3 x AAA battery holder with on-off switch and 2-pin JST PH connector.](https://cdn-shop.adafruit.com/640x480/727-07.jpg) ### Part: Perfboard Plates quantity: 1 Bakelite, universal, pack of 10 [Perfboard Plates](https://www.adafruit.com/product/2670) ### Part: Slide Switch quantity: 1 SPDT - breadboard friendly [Slide Switch](https://www.adafruit.com/product/805) ### Part: Short Female Headers for Feather quantity: 1 One 12-pin and one 16-pin [Short Female Headers for Feather](https://www.adafruit.com/product/2940) ## Helpful Tools ### Super Scissors [Super Scissors](https://www.adafruit.com/product/1599) Save your scissors! Instead of using your nice shears (and dulling them) or wire cutters (not right for the job) - use these super scissors. They're meant for engineering/maker cutting jobs such as cutting plastic, leather, copper sheet/wire, even coaxial & ribbon cables. There's a... In Stock [Buy Now](https://www.adafruit.com/product/1599) [Related Guides to the Product](https://learn.adafruit.com/products/1599/guides) ![Very strong looking scissors with comfy grip](https://cdn-shop.adafruit.com/640x480/1599-09.jpg) - [Next Page](https://learn.adafruit.com/ble-synth-with-the-feather-nrf52840-and-circuit-playground-bluefruit/electronics.md) ## Featured Products ### Circuit Playground Bluefruit - Bluetooth® Low Energy [Circuit Playground Bluefruit - Bluetooth® Low Energy](https://www.adafruit.com/product/4333) **Circuit Playground Bluefruit** is our third board in the Circuit Playground series, another step towards a perfect introduction to electronics and programming. We've taken the popular Circuit Playground Express and made it even better! Now the main chip is an nRF52840... Out of Stock [Buy Now](https://www.adafruit.com/product/4333) [Related Guides to the Product](https://learn.adafruit.com/products/4333/guides) ### Adafruit Feather nRF52840 Express [Adafruit Feather nRF52840 Express](https://www.adafruit.com/product/4062) The **Adafruit Feather nRF52840 Express** is the new Feather family member with Bluetooth® Low Energy and _native USB support_ featuring the nRF52840!  It's our take on an 'all-in-one' Arduino-compatible + Bluetooth® Low Energy with built-in USB... Out of Stock [Buy Now](https://www.adafruit.com/product/4062) [Related Guides to the Product](https://learn.adafruit.com/products/4062/guides) ### Adafruit STEMMA Speaker - Plug and Play Audio Amplifier [Adafruit STEMMA Speaker - Plug and Play Audio Amplifier](https://www.adafruit.com/product/3885) Hey, have you heard the good news? With Adafruit STEMMA boards you can easily and safely plug sensors and devices together, like this **Adafruit STEMMA Speaker - Plug and Play Audio Amplifier**. Like the name implies, it's got a class D audio amplifier on board, and our... Out of Stock [Buy Now](https://www.adafruit.com/product/3885) [Related Guides to the Product](https://learn.adafruit.com/products/3885/guides) ### Colorful Round Tactile Button Switch Assortment - 15 pack [Colorful Round Tactile Button Switch Assortment - 15 pack](https://www.adafruit.com/product/1009) Little clicky switches are standard input "buttons" on electronic projects. These work best in a PCB but [can be used on a solderless breadboard as shown in this tutorial](http://www.ladyada.net/learn/arduino/lesson5.html). The pins are normally open (disconnected) and... In Stock [Buy Now](https://www.adafruit.com/product/1009) [Related Guides to the Product](https://learn.adafruit.com/products/1009/guides) ### 3 x AAA Battery Holder with On/Off Switch and 2-Pin JST [3 x AAA Battery Holder with On/Off Switch and 2-Pin JST](https://www.adafruit.com/product/727) This battery holder connects 3 AAA batteries together in series for powering all kinds of projects. We spec'd these out because the box is slim, and 3 AAA's add up to about 3.3-4.5V, a very similar range to Lithium Ion/polymer (Li-Ion) batteries and have an on-off switch. That makes... In Stock [Buy Now](https://www.adafruit.com/product/727) [Related Guides to the Product](https://learn.adafruit.com/products/727/guides) ### Bakelite Universal Perfboard Plates - Pack of 10 [Bakelite Universal Perfboard Plates - Pack of 10](https://www.adafruit.com/product/2670) Make your next project as you imagine it with prototyping perfboards that can easily be cut with scissors like these **Bakelite Universal Perfboard Plates**! We wanted a perfboard that was both customizable and durable and In Stock [Buy Now](https://www.adafruit.com/product/2670) [Related Guides to the Product](https://learn.adafruit.com/products/2670/guides) ### Breadboard-friendly SPDT Slide Switch [Breadboard-friendly SPDT Slide Switch](https://www.adafruit.com/product/805) These nice switches are perfect for use with breadboard and perfboard projects. They have 0.1" spacing and snap in nicely into a solderless breadboard. They're easy to switch no matter what size fingers you have, but not so easy that they'll get flipped by accident. Work great as... In Stock [Buy Now](https://www.adafruit.com/product/805) [Related Guides to the Product](https://learn.adafruit.com/products/805/guides) ### Short Headers Kit for Feather - 12-pin + 16-pin Female Headers [Short Headers Kit for Feather - 12-pin + 16-pin Female Headers](https://www.adafruit.com/product/2940) These two  **Short**   **Female Headers**  alone are, well, lonely. But pair them with any of our [Feather](https://www.adafruit.com/categories/777) boards and you're in business! These headers are particularly cute and... Out of Stock [Buy Now](https://www.adafruit.com/product/2940) [Related Guides to the Product](https://learn.adafruit.com/products/2940/guides) ## Related Guides - [Introducing the Adafruit nRF52840 Feather](https://learn.adafruit.com/introducing-the-adafruit-nrf52840-feather.md) - [Adafruit Circuit Playground Bluefruit](https://learn.adafruit.com/adafruit-circuit-playground-bluefruit.md) - [Adafruit STEMMA Speaker](https://learn.adafruit.com/adafruit-stemma-speaker.md) - [Circuit Playground TFT Gizmo Dreidel](https://learn.adafruit.com/circuit-playground-tft-gizmo-dreidel.md) - [Bluefruit TFT Gizmo ANCS Notifier for iOS](https://learn.adafruit.com/ancs-gizmo.md) - [CLUE Rock, Paper, Scissors Game using Bluetooth](https://learn.adafruit.com/rock-paper-scissors-circuitpython.md) - [Wirelessly Program a Circuit Playground Bluefruit Using the File Glider App ](https://learn.adafruit.com/how-to-transfer-files-to-a-circuit-playground-bluefruit-using-the-fileglider-app.md) - [ Memory-saving tips for CircuitPython](https://learn.adafruit.com/memory-saving-tips-for-circuitpython.md) - [¡Bienvenido a CircuitPython!](https://learn.adafruit.com/bienvenido-a-circuitpython-2.md) - [Which CircuitPython Board is Right for You?](https://learn.adafruit.com/choose-your-circuitpython-board.md) - [CircuitPython BLE Libraries on Any Computer](https://learn.adafruit.com/circuitpython-ble-libraries-on-any-computer.md) - [Wirelessly Code your Bluetooth Device with CircuitPython](https://learn.adafruit.com/wirelessly-code-your-bluetooth-device-with-circuitpython.md) - [AdaBox 014](https://learn.adafruit.com/adabox014.md) - [CLUE Metal Detector in CircuitPython](https://learn.adafruit.com/clue-metal-detector-circuitpython.md) - [NeoPixel Badge Lanyard with Bluetooth LE](https://learn.adafruit.com/bluetooth-neopixel-badge-lanyard.md) - [DIY Quiz Show Controller System](https://learn.adafruit.com/quiz-show-controller-keyboard-bluetooth.md) - [PyLeap Tone Piano for Circuit Playground Bluefruit](https://learn.adafruit.com/pyleap-tone-piano-for-cpb.md)