esp-idf/examples/peripherals/rmt/led_strip

RMT Transmit Example -- LED Strip

(See the README.md file in the upper level 'examples' directory for more information about examples.)

Although RMT peripheral is mainly designed for infrared remote applications, it can also support other generic protocols thanks to its flexible data format. WS2812 is a digital RGB LED which integrates a driver circuit and a single control wire. The protocol data format defined in WS2812 is compatible to that in RMT peripheral. This example will illustrate how to drive an WS2812 LED strip based on the RMT driver.

How to Use Example

Hardware Required

• A development board with ESP32 SoC (e.g., ESP32-DevKitC, ESP-WROVER-KIT, etc.)
• A USB cable for Power supply and programming
• A WS2812 LED strip

Connection :

                             --- 5V
                              |
                              +
GPIO18 +-----------------+---|>| (WS2812)
                        DI    +
                              |
                             --- GND

Configure the Project

Open the project configuration menu (idf.py menuconfig).

In the Example Configuration menu:

• Set the GPIO number used for transmitting the IR signal under RMT TX GPIO option.
• Set the number of LEDs in a strip under Number of LEDS in a strip option.

Build and Flash

Run idf.py -p PORT flash monitor to build, flash and monitor the project.

(To exit the serial monitor, type Ctrl-].)

See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.

Example Output

Connect the DI signal of WS2812 LED strip to the GPIO you set in menuconfig.

Run the example, you will see a rainbow chasing demonstration effect. To change the chasing speed, you can update the EXAMPLE_CHASE_SPEED_MS value in led_strip_main.c file.

Troubleshooting

For any technical queries, please open an issue on GitHub. We will get back to you soon.