.. note:: Hello, welcome to the SunFounder Raspberry Pi & Arduino & ESP32 Enthusiasts Community on Facebook! Dive deeper into Raspberry Pi, Arduino, and ESP32 with fellow enthusiasts. **Why Join?** - **Expert Support**: Solve post-sale issues and technical challenges with help from our community and team. - **Learn & Share**: Exchange tips and tutorials to enhance your skills. - **Exclusive Previews**: Get early access to new product announcements and sneak peeks. - **Special Discounts**: Enjoy exclusive discounts on our newest products. - **Festive Promotions and Giveaways**: Take part in giveaways and holiday promotions. 👉 Ready to explore and create with us? Click [|link_sf_facebook|] and join today! .. _py_neopixel: 3.3 Controlling an RGB LED Strip =========================================================== In this lesson, we'll learn how to control an **RGB LED strip** (specifically the WS2812 type) using the Raspberry Pi Pico 2 and MicroPython. The WS2812 is a smart LED that integrates a control circuit and an RGB chip into a 5050-sized LED package. Each LED has its own built-in controller, which allows us to control each LED individually using a single data line. This means we can change the color and brightness of each LED on the strip independently. **What You'll Need** In this project, we need the following components. It's definitely convenient to buy a whole kit, here's the link: .. list-table:: :widths: 20 20 20 :header-rows: 1 * - Name - ITEMS IN THIS KIT - LINK * - Newton Lab Kit - 450+ - |link_newton_lab_kit| You can also buy them separately from the links below. .. list-table:: :widths: 5 20 5 20 :header-rows: 1 * - SN - COMPONENT - QUANTITY - LINK * - 1 - :ref:`cpn_pico_2` - 1 - |link_pico2_buy| * - 2 - Micro USB Cable - 1 - * - 3 - :ref:`cpn_breadboard` - 1 - |link_breadboard_buy| * - 4 - :ref:`cpn_wire` - Several - |link_wires_buy| * - 5 - :ref:`cpn_ws2812` - 1 - |link_ws2812_buy| **Circuit Diagram** |sch_ws2812| **Wiring Diagram** |wiring_ws2812| Be cautious with the current draw. While the Pico's VBUS pin can supply power for a small number of LEDs (like 8), using more LEDs may require an external power supply to prevent overloading the Pico. **Writing the Code** .. note:: * Open the ``3.3_rgb_led_strip.py`` from ``newton-lab-kit/micropython`` or copy the code into Thonny, then click "Run" or press F5. * Ensure the correct interpreter is selected: MicroPython (Raspberry Pi Pico).COMxx. * Here you need to use the library called ``ws2812.py``, please check if it has been uploaded to Pico, for a detailed tutorial refer to :ref:`add_libraries_py`. .. code-block:: python import machine from ws2812 import WS2812 # Initialize the LED strip led_strip = WS2812(machine.Pin(0), 8) # Using GP0, 8 LEDs # Set colors for each LED led_strip[0] = [255, 0, 0] # Red led_strip[1] = [0, 255, 0] # Green led_strip[2] = [0, 0, 255] # Blue led_strip[3] = [255, 255, 0] # Yellow led_strip[4] = [0, 255, 255] # Cyan led_strip[5] = [255, 0, 255] # Magenta led_strip[6] = [255, 255, 255] # White led_strip[7] = [128, 128, 128] # Gray # Update the LED strip to show the colors led_strip.write() When this code is running, the WS2812 LED strip connected to pin GP0 with 8 LEDs will display the following colors: * **LED 0**: Red (255, 0, 0) * **LED 1**: Green (0, 255, 0) * **LED 2**: Blue (0, 0, 255) * **LED 3**: Yellow (255, 255, 0) * **LED 4**: Cyan (0, 255, 255) * **LED 5**: Magenta (255, 0, 255) * **LED 6**: White (255, 255, 255) * **LED 7**: Gray (128, 128, 128) **Understanding the Code** #. Import Libraries: * ``machine``: Provides access to hardware-related functions. * ``WS2812``: The library to control the WS2812 LED strip. #. Initialize the LED Strip: * ``led_strip = WS2812(machine.Pin(0), 8)``: Initializes the LED strip connected to pin GP0 with 8 LEDs. #. Set Colors: * ``led_strip[0] = [255, 0, 0]``: Assigns a color to each LED using RGB values (Red, Green, Blue), ranging from 0 to 255. #. Update the LED Strip: * ``led_strip.write()``: Sends the color data to the LED strip to display the colors. **Let's Make a Flowing Rainbow Effect!** Now, we'll create a colorful flowing light effect by randomly generating colors and shifting them along the strip. .. code-block:: python import machine from ws2812 import WS2812 import utime import urandom # Number of LEDs in the strip NUM_LEDS = 8 # Initialize the LED strip with 8 LEDs led_strip = WS2812(machine.Pin(0), NUM_LEDS) def flowing_light(): # Shift colors along the strip for i in range(NUM_LEDS - 1, 0, -1): led_strip[i] = led_strip[i - 1] # Generate a random color for the first LED led_strip[0] = [urandom.getrandbits(8), urandom.getrandbits(8), urandom.getrandbits(8)] # Update the strip led_strip.write() # Small delay for smooth animation utime.sleep_ms(100) # Main loop while True: flowing_light() When the code runs, the LED strip displays a flowing dynamic effect with random colors, where a new random color is introduced at the beginning and shifts towards the end with each cycle. **Understanding the Code** #. Random Color Generation: Generates a random RGB color where each component ranges from 0 to 255. .. code-block:: python [urandom.getrandbits(8), urandom.getrandbits(8), urandom.getrandbits(8)] #. Shifting Colors: Moves each LED's color to the next position, creating a flowing effect. .. code-block:: python for i in range(NUM_LEDS - 1, 0, -1): led_strip[i] = led_strip[i - 1] #. Infinite Loop: Continuously updates the LED strip to keep the animation running. .. code-block:: python while True: flowing_light() **Experimenting Further** * **Adjusting Speed**: Modify ``utime.sleep_ms(100)`` to make the flowing effect faster or slower. * **More LEDs**: If you have a longer strip, change the number in ``WS2812(machine.Pin(0), number_of_leds)`` accordingly. * **Custom Animations**: Experiment with different patterns and color combinations to create your own animations. **Conclusion** You've successfully learned how to control an RGB LED strip using the Raspberry Pi Pico 2 and MicroPython! This opens up a world of possibilities for creating stunning light displays, mood lighting, or even interactive art projects.