LED POVstick With Bluetooth Low Energy

This instructable shows you how to build a lightwriter stick with RGB LEDs which is controllable via BLE from your phone!
Now that the dark season starts and you need to take long exposure pictures: With this stick you can write your signature into the picture, or a motivational quote, or a declaration of love, a QR-code, a web-adresse, or many things else…
It covers several topics of development:
building the hardware programming the Cypress BLE chipset with C make your own app to control it.”

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