# RMT Transmit Example -- Morse Code (See the README.md file in the upper level 'examples' directory for more information about examples.) This example mainly illustrates how to transmit the [Morse code](https://en.wikipedia.org/wiki/Morse_code) using 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 LED, a speaker or an earphone Connection : ``` 330R LED GPIO18 +----/\/\/\----+------|>|-----+ GND | | /| +-+ | Speaker | | | or +-+ | earphone | \| | +--------------+ 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` optin. ### 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 all the steps to configure and use the ESP-IDF to build projects. * [ESP-IDF Getting Started Guide on ESP32](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/get-started/index.html) * [ESP-IDF Getting Started Guide on ESP32-S2](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/get-started/index.html) * [ESP-IDF Getting Started Guide on ESP32-C3](https://docs.espressif.com/projects/esp-idf/en/latest/esp32c3/get-started/index.html) ## Example Output To be able to see and hear the message output by the RMT, connect an LED and a speaker or an earphone (be careful it might make a large noise) to the GPIO you set in the menuconfig. Run the example, you will see the following output log: ``` bash ... I (304) example: Configuring transmitter I (2814) example: Transmission complete ... ``` ## Troubleshooting For any technical queries, please open an [issue](https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.