ESP32 RMT-based Adjustable PWM Example

A demonstration project showcasing PWM signal generation with adjustable duty cycle using ESP32's RMT (Remote Control) peripheral through ESP-IDF framework.

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Project Description

This project implements a PWM generation solution using ESP32's RMT (Remote Control) peripheral, specifically designed to supplement the built-in LEDC PWM modules when all hardware PWM channels are occupied. By creatively repurposing the typically IR-focused RMT peripheral, developers can obtain additional PWM outputs while maintaining flexible duty cycle control.

Key Features

✅ Provides extra PWM channels when LEDC resources are exhausted
✅ Dynamic duty cycle adjustment at runtime
✅ Configurable PWM frequency (10kHz default)
✅ Parallel operation with existing LEDC PWM modules
✅ Resolution up to 100 steps

Hardware Requirements

ESP32 series development board (Tested with ESP32-C3-DevKitM-1 V1.0)
Oscilloscope for signal verification

Hardware Connection

Default Configuration:

Signal GPIO: GPIO19
RMT Channel: RMT_CHANNEL_0

Getting Started

Prerequisites

ESP-IDF v5.x+ installed
ESP32 toolchain setup
Serial terminal application (e.g., screen, minicom)

Installation & Usage

Clone repository:

git clone https://github.com/oldrev/esp32c3-rmt-pwm-demo.git
cd esp32c3-rmt-pwm-demo.git

Build and flash:

bash
idf.py build

bash
idf.py flash monitor

Observe PWM wave pattern (cycle time: 10 seconds)

License

Distributed under the Apache 2.0 License. See LICENSE for more information.

Contributing

Contributions are welcome! Please open an issue or submit a PR for any improvements.