Square with 4 WS2812 RGB LEDs and built-in driver

Description

Square Neopixel module with 4 RGB LED diodes that can be individually controlled, each capable of producing 256 shades of its color, resulting in a total of 16,777,216 colors. The data channel for communication is serial, One-Wire type, and can be controlled with microcontrollers such as Arduino, PIC, mbed, etc. The refresh frequency can be set as desired, making certain light effects imperceptible. Multiple rings can be cascaded to create various effects. Power supply: 5 Vdc.

Warning! Since the protocol is very sensitive to timing, it requires a real-time microcontroller such as an AVR, Arduino, PIC, mbed, etc. It cannot be used with a Linux-based microcomputer or microcontrollers like Netduino or Basic Stamp. The Adafruit NeoPixel library (www.adafruit.com), freely available, is specific to Arduino.

Neopixel Technology

Neopixel technology allows for “smart” RGB LEDs with onboard controllers, easily integrated into the Arduino environment thanks to proprietary libraries that Adafruit (www.adafruit.com) makes freely available. A special feature of Neopixel LEDs is that they can be cascaded so that the data line passes from one to the next, but the price to pay is that beyond a certain number of LEDs, the management speed must be significantly reduced; because of this, if you need to create matrices to display fast graphics, you must use many lines with few LEDs each. Each RGB LED can be individually controlled via a specific command inserted into the serial string and can produce up to 256 shades of its color, resulting in a total of 16,777,216 color combinations. Neopixel is practically a solution that integrates a driver and its RGB LED into an SMD case, allowing direct LED-by-LED control. The data channel used for communication with Neopixel LEDs and therefore with the strips is similar to the One-Wire type. The power supply for Neopixel LEDs is 5 volts; communication occurs at a maximum of 800 kbps. The Neopixel system command protocol involves sending groups of three bytes in a 24-bit string, each containing the lighting state of each base color (first the eight bits of green, then those of red, and finally those of green).

Documentation and Useful Links

• NeoPixel Überguide
• NeoPixel Library